International Guild of Knot Tyers Forum

General => Knotting Concepts & Explorations => Topic started by: agent_smith on July 13, 2013, 11:45:54 AM

Title: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 13, 2013, 11:45:54 AM
Greetings all.

I have uploaded a DRAFT paper on the 'Analysis of Bowlines'.

Site: http://www.paci.com.au/knots.php (file is located second from the top in the table) - 2.17 MB download as a PDF file.

I invite all interested persons to download, review and then make critical comment on the paper.

Comments can be made in this post.

Please keep in mind that this is merely a draft paper - it is not complete and it certainly is 'not set in stone'. Constructive criticism is more likely to be acted upon... and if you want your contribution to be acknowledged in the paper, please advise accordingly.

Photos of knots are always welcome, however they must be of a suitable quality. No dark or shaded backgrounds will be accepted (must be white/transparent). Photos of knots must include 'front' and 'rear' aspect and must clearly show the knots structure.

IMPORTANT NOTICE ON COPYRIGHT
This document is supplied in good faith and is freely available for download in the public domain. Any person choosing to contribute photos forfeits all copyright claims including forfeiture of any royalties or payments. Contributions are understood to made for no monetary gain, reward or profit - and are made as a contribution to world knowledge. PACI Pty Ltd (the owner of the website) and Mark Gommers will not be held liable for any claim in relation to any contributions made.

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 15, 2013, 01:33:19 AM
Thanks 75RR,

A good suggestion indeed. Unfortunately, 2 things will stop me from doing this:
1. Time; and
2. Resources.

I am doing this project on a shoe string budget and in-between work and other life commitments (like supporting my daughter in hockey and also field archery).

I must also point out that the paper isn't really intended as a step-by-step knot tying guide... its about documenting bowlines and examining the theory of their structure.

Maybe someone else could use this paper as a starting point for another more detailed paper (like a PhD thesis)?

......

Speaking of which, thanks to those who have decided to message me personally (particularly X1) - I am re-writing page 10 and making and other changes - including getting rid of a few typos...


Mark

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 15, 2013, 05:23:16 AM
A new draft VER 2.0 has been uploaded and is ready for review and comment.

Change list:
[ ] changed foreword - rewritten
[ ] added contributors page
[ ] page 3 - removed 'E' and also capitalised letter 't' in tail to Tail - also expanded information on the collar
[ ] page 5 - re arranged para 3 to place emphasis that the nipping turn is the key component of all bowlines
[ ] page 8 - same as page 5, re-arranged wording to place more emphasis on the nipping turn
[ ] page 9 - re-wrote information on 'Eskimo' bowline
[ ] page 10 - emphasised lack of nipping turn (bold red font)
[ ] page 11 - complete re-write (many concepts changed and/or added), including capstan effect at SPart - needs further review
[ ] page 12 - added call-out boxes to draw attention to whats happening to the collar
[ ] page 14 - added emphasis on the fact there are 3 rope diameters inside the nipping turn (Lee's locked bowline)
[ ] page 15 - re-wrote information about Scott's locked bowline
[ ] page 16 - significant re-write of the Water bowline - needs more work
[ ] page 23 - added more information about the 'anti' / Myrtle characterisation

+ a few typos and images were fixed here and there...

I would be pleased to list additional contributors in the paper (also need to know your nationality).


Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 17, 2013, 07:03:15 PM
   Congratulations, Mark. Your paper gets better by the day !  :)
   I would like to propose two most slight "modifications", almost at the level of splitting hairs, in the two "locked" bowlines you show at page 15. In fact, the knots remain the same, but why we should not try to improve something even slightly ?
   In the first locked bowline you show, I had re-dressed the "Lehman s lock" in a slightly different way, by forcing the tail to settle to another orientation, perpendicularly to the Standing Part ( See the first two attached pictures, and read (1)). Does it matter so much ? No, but if there is a difference, it would be beneficial rather than detrimental to the knot, I believe. The meeting point of the Tail and the Standing part is the last line of defence against slippage of the knot, so I think that if, at this point, the two segments meet at a right angle, they can "bite" harder into each other s body - and this enhances the generated friction forces.
   Now, perhaps much more interesting, is the fact that this bowline is TIB, and, moreover, that it can be tied by the same simple "three bights" method many other simple TIB bowlines do - although, in this case, the result should be dressed a little more.
   Believe it or nor, I had completely forgotten this bowline - I can not even remember if it was on all your previous papers. Evidently, I was not much impressed by it - but the fact that it is TIB, and can be tied as a midline loop, makes it much more versatile and really useful. I had (re-)discovered it when I tied all the possible TIB loops that can be tied by this method, and rearranged their strands in every possible way. I had presented it in a new thread some weeks ago, still ignoring that it was essentially the same knot as the locked by the "Lehman s lock" bowline - and neither Lehman himself noticed and/or commented on this ( he might well had noticed and/but not commented, so I write and/or  :)  ). It was only a few days ago, when I was reading your new version, that I had realized the identity.
   So, I think it would be better to present it in the slightly different form I show, and also characterize it, emphatically, as a TIB bowline - there are not many TIB bowlines in your collection !  :)
   The second "modification" / hair splitting is also as slight as the first one. ( See the last two attached pictures, and read (2)).The "Scot s locked bowline" can be tied so that the tail will follow a wider path, around three rope diameters - there are stiff ropes that would resist to follow a turn as sharp as in the knot you show, especially if the segment which should make the turn is a tail - that is, it is loaded only from the one side. SS369 himself had seemed to approve this "modification", but he may have forgotten it now !  :)  I believe that, when tied on stiff static ropes, the tail will remain in place easier in the knot tied like this, and it will not sag between the Standing end and the rim of the nipping turn at any time.

1.   http://igkt.net/sm/index.php?topic=4476.0 (http://igkt.net/sm/index.php?topic=4476.0)
2.   http://igkt.net/sm/index.php?topic=19.msg20616#msg20616 (http://igkt.net/sm/index.php?topic=19.msg20616#msg20616)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 18, 2013, 02:59:40 AM
Thanks X1 - and yes, I still have some way to go with this paper.

I am motivated to get it right and, to also achieve general agreeance on the content of the paper.

There are areas of work that I am still unhappy with - particularly with the 'anti' bowlines, the 'eskimo' bowlines and bowlines based on crossing hitch nipping turn structure. I am struggling to rationalise these classes of bowline. In particular, I may be totally wrong in what I have labelled as an 'anti' bowline. But, I thought it best to just put the paper out there in the public domain to solicit feedback.

As with your latest bowline images, I really would appreciate some high quality photos (front and back) which clearly show the structure. Its starting to become a bit overwhelming for me to photograph everything - and I am running out of time. It would also be nice to get some comment from SS369 on these variations too.

If I had high quality photos from contributors, it would speed things up considerably :)

...

Current changes that I have made (ie errors fixed):
[ ] fixed all references to bowlines that have 3 rope diameters inside the nipping turn. Deleted 'reduces' and inserted 'increases'. The 3 rope diameters increase the radius of the nipping turn.
[ ] fixed the reference to eye knot based on 'Riggers bend' at page 10. The core (aka 'nub') of the knot is not actually a riggers bend. Reference now states that the eye knot is based on 2 interlocking overhand knots (removed any reference to riggers bend)
[ ] a couple a grammatical errors have also been fixed
[ ] have also added an image of an 'eye bolt' to show the reasoning behind calling bowlines 'eye-knots' instead of loop knots. For example, if I went into a hardware/tool shop and asked the salesperson for a 'loop bolt' or a 'bight bolt' - I would probably get puzzling looks. However, if I asked for an 'eye-bolt' it would be easily understood. The eye of the 'eye-bolt' is the connective component - just like the 'eye' of a bowline is also intended as a connective component.

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on July 18, 2013, 04:10:33 AM
[ ] have also added an image of an 'eye bolt' to show the reasoning behind calling bowlines 'eye-knots' instead of loop knots.
But loops come in many different sizes, not just eye size or eye proportion.  When it gets big, will you call it a "hoop knot" and show a picture of a hoop as "reasoning"?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 18, 2013, 06:09:24 AM
But loops come in many different sizes, not just eye size or eye proportion.  When it gets big, will you call it a "hoop knot" and show a picture of a hoop as "reasoning"?
   Eyes come in many different sizes, too !  :)  The "eye" can mean a shape, independently of its size. If we have something hollow, and more rounded from the one side, but more pinched from the other, we tend to call it an "eye". Also, hollow places in the middle of extended flat regions are called "eyes", too : In meteorology, the central regions of vortices in the clouds are called "eyes" : The eye of the cyclone, the eye of the storm, the eye of the tornado ... For yet bigger eyes, see (1)(2).

1.  http://www.daviddarling.info/encyclopedia/E/Eyes.html (http://www.daviddarling.info/encyclopedia/E/Eyes.html)
2.  http://en.wikipedia.org/wiki/Black_Eye_Galaxy (http://en.wikipedia.org/wiki/Black_Eye_Galaxy)
   
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on July 18, 2013, 06:30:54 AM
But loops come in many different sizes, not just eye size or eye proportion.  When it gets big, will you call it a "hoop knot" and show a picture of a hoop as "reasoning"?
   Eyes come in many different sizes, too !  :)
But in flexible rope, big loops end up looking very long, floppy, curvy and not very eye-like at all. 

This all dances around the larger issue of why anyone would want to abandon widespread and long established terminology (and names!) that prefer "loop".
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 18, 2013, 10:49:35 AM
But in flexible rope, big loops end up looking very long, floppy, curvy and not very eye-like at all.

Not when they are loaded, attached on a pole, a bollard, a ring, a hook, the waist of the climber, another eyeknot, etc. Do eyes themselves end up looking very eye-like, when they are closed ?

This all dances around the larger issue of why anyone would want to abandon widespread and long established terminology (and names !) that prefer "loop".
  The word "eye", in the sense of a "closed" hook, is widespread and long established, too : I was told about the eye of the needle from my grand mother, the wiser human being I had ever met - who lost a needle, that fell into the carpet, on which I stepped on, bare footed  - the needle was broken inside my left foot s sole, and it was removed only after an operation in real vivo, without anaesthesia, for some looong minutes ( it was still dangerous to perform anaesthesia to very small children ). I still remember my horror, as four men were holding me on the chair while the surgeon was digging, I still have the scars, and I will never forget what the eye of the needle is !  :) 
   I am an advocate of neither neologisms, nor new names for things already name, without a reason. I was convinced about the usefulness of a more descriptive, as it really is, and less ambiguous name in this case by dan Lehdman - although his persuasive ability on me, and/or my ability to be persuaded for something by him, are very limited, indeed !  :)   Now, nothing will be carved in stone ! Even if this term is "established" ( if a knotting term can ever be established - there are so many different names used for the same things, and so many things that have no names, that we should not worry too much about it...) , we can not predict if it will survive into the flow of time or not, or how much later it will be replaced by something else. Also, we do not know which language will be the lingua franca of the world - in other words, we do not know the shape of the eyes of the people that will speak this language !  :)
   Instinctively, when I tuck a working end through a small opening of an already half-tied nub - something I do very often - I feel as I drive a thread through the eye of the needle - and as I grow older, and my sight deteriorates, I feel it more vividly !  :) So, the word "eye" makes more sense to me in this case, than the word "loop". Also, the word "eye-knot" is more descriptive, in my mind, than the word "loop knot". However, as my knowledge and experience of English is rudimental, I can not have a say on this issue - on top of so many issues I imagine I can say something, and that something will be heard by somebody  :)  I will simply follow the consensus of the community, whatever that might be. There is no better article on the most important end of line eye-knots/loop-knots we have, the bowlines, other than this one by Mark Gommers - and I doubt that somebody else will write something else in the foreseen future. Of course,  I would like to listen to the learned opinion of Derek Smith and Dave Root, and I had already suggested to Mark Gommers to ask them about this. However, my primary concern is to find a way to distinguish the set of the crossing knot / hitch based bowlines, from the subset of the "Eskimo" bowlines, for example, i.e. issues that have to do with the structural differences between "similar" knots, and not the names of knots !
 
P.S. When we speak of the generic shape of an eye, we tend to imagine, i.e. " something hollow, and more rounded from the one side, but more pinched from the other " - AND, we tend to imagine that, in a human face, the more round sides of the eyes would be close to the nose, and the more pinched sides close to the ears. See the eyes on a human face where we can say that what really happens is the exact opposite . Bird s eyes are also more round, and the eyes of nocturne birds, like the owls, have the more peculiar shapes of all.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on July 19, 2013, 04:27:03 PM
[ ] have also added an image of an 'eye bolt' to show the reasoning behind calling bowlines 'eye-knots' instead of loop knots.
But loops come in many different sizes, not just eye size or eye proportion.  When it gets big, will you call it a "hoop knot" and show a picture of a hoop as "reasoning"?

This is getting silly, but does suggest that the document's
image goes in the wrong direction for rationale : i.e., it is
NOT really the shape but the *logical* notion of "eye"
that is intended; for this, I suggest showing not an eye bolt
but an eye splice --which is precisely from where use comes.
(The close shape too much suggests the wrong rationale.)

As for going against popular nomenclature: yes, that's a good
consideration; the choice to do so notwithstanding usage
is that "loop" means too many things --i.p., rockclimbers
et al. make "loops" by tying ends of a single line together
(which might also be called "runners", "slings", "rings"(?)).
And the bowline is said to be the marriage of a "loop"
and bight.  (And we should note that "bight" has odd
implications of contrast between the "halved"/folded
rope (into, um, would that be like a "loop"?!) and the
rather UNcrooked/straight mid-section of line
--between "with a bight" and "in the bight" !!)


Here we should ask : What to other languages do?


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 19, 2013, 07:44:49 PM
This.. does suggest that the document's image goes in the wrong direction for rationale : i.e., it is NOT really the shape but the *logical* notion of "eye" that is intended; for this, I suggest showing not an eye bolt but an eye splice --which is precisely from where use comes. (The close shape too much suggests the wrong rationale.)
   Although I agree that it is better if the document had shown an eye splice, all the other "reasoning" of this paragraph is, apparently, wrong ! One can easily shift the goal posts just a little bid, and ask : And why has the eye splice been called an "eye" in the first place ?  :)  It is the shape, and nothing else, that was the initial reason for this moniker.
   When I saw the "closed" form of this "eye bolt", I searched in the "Google Images" to see if this name is also used for the "open" similar screws I had in mind.  It is, but I do not know if those screws are also known by any other name, or not, and what comes to the average person s mind with the name "eye bolt". In the relevant Wikipedia article, the "eye bolt" is shown in its "open" form. (1). See the attached pictures.

1. http://en.wikipedia.org/wiki/Eye_bolt (http://en.wikipedia.org/wiki/Eye_bolt)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 22, 2013, 04:19:04 AM
Hello SS369'

I have attached some photos of your creation (Bowline - Scotts collar-weave).

Couldn't send via 'personal message' as I couldn't figure out how to attach images... also, not sure of your correct email address.

Had a bit of trouble dressing these knots - found that I had to pay attention to pulling down the eye-legs to achieve the desired symmetry. I also edited the colour saturation and tonal levels to achieve a richer blue. To accommodate the limitations of this site, I had to compress the images. if you want high resolution images, I'll need you email address...

As for its inclusion in the 'Bowlines Analysis paper' - it is definitely worth the effort. I have not field tested this knot so can't comment on stability and security. However, at first instance, the weave structure does appear to inhibit tail movement. This is an interesting take on achieving a lock - as it tackles the problem pre-insertion through the nipping (ie by altering the collar structure) rather than post insertion through the nipping turn.

According to theory postulated in the paper, it must be a Bowline because it has a nipping turn (a key component of all Bowlines) and that nipping turn grips and stabilises the bigh component. The difference in Scott's collar-weave to the fundamental "#1010" is the collar structure. Creating the weave pattern appears to inhibit tail movement. Further study is required...

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 22, 2013, 01:06:17 PM
DRAFT VER 2.1 is uploaded for comment.

PDF file is now 2.47MB in size.

Not sure how much more time I can spend on this project...

Change:
[ ] changed foreword (intro) page - opening paragraph modified after Dan Lehman suggestion
[ ] Tidied up some image of the girth hitch bowline
[ ] pages 5, 6 & 7 all new (new expanded info on concepts of PET and TIB) - needs more work
[ ] page 17 - new images of Yosemite Bowline (warnings)
[ ] page 20 - added new image of #1012
[ ] page 27 - tidied up images
[ ] page 28 - Added new images of Scotts woven collar bowline
[ ] modified definitions of anti versus Myrtle bowline structures (pages 9 and 12)

Still more typos and errors to fix...


Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on July 22, 2013, 01:28:35 PM
God day Mark.

Thank you for the inclusion in the paper.

I find that dressing is not so difficult if one grabs the tail and its accompanying leg and pulling them as you hold the nipping loop. I have found that this works with the stiffest of ropes that I own.
The knot does not need to be super tight to do its work.

As for the high resolution pictures: Thank you, no need, I have the "real thing".  ;-)

To email me or any member of the Forum, just click envelope icon under the member's nick-name.

The paper is a labor of love and it shows. Thank you for your efforts.

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 24, 2013, 03:53:41 PM
VER 2.1a is uploaded.

Its late at night.... briefly; several typos have been corrected and have also rooted out all the lingering errors with anti-bowlines and crossed-bight bowlines.

Also rooted out typos/grammar errors with regard to the nipping turn / closed helix structure.

The TIB page showing how #1047 can be tied in the bight versus re-threaded is partly fixed. I have to take yet another photo of the the first stage (#524) but without the harness. VER 2.1a still shows the F8 being re-threaded through a harness which may confuse some readers... once the harness is removed from the image - it will just show an F8 eye-knot being tied in the 2 stage method as a single-strand.

I am also intending to include another obvious simple lock - that being a strangled double overhand knot around the eye leg (its simple and it works).

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 24, 2013, 06:15:54 PM
I am also intending to include another obvious simple lock - that being a strangled double overhand knot around the eye leg (its simple and it works).
  Although this is, unquestionably, the most naive way one can lock the Tail, it was probably one of the first and the most used - so I think it will not make any harm if you include it in your collection. It is not "simple" in any way, regarding the knot per se : it consumes more rope length, it makes the knot more extended, it requires more tucks of the working end (= it requires more time to be tie and untied), and the path of the working end is more convoluted than in most other secure bowlines. However, conceptually, and for somebody who has not yet understood the working of the bowline in much depth, it is the simplest idea - that, as you say, works.
   The same happens for an even bulkier secure bowline, the Double collar ( two collars) Girth hitch based bowline - the "Mirrored"  bowline. Although it is not "simple" regarding the knot itself, it is simple conceptually : the Tail makes a second U turn, around the eye leg this time, and then returns back, going "upwards", following the same path it had followed going "downwards". Moreover, the base Girth hitch used as its double nipping structure is very easy to tie, and the tucking of the working end is straightforward, because the line penetrates both nipping turns at the same time, in its path "downwards" as well as "upwards". Therefore, I believe that the pink boot it was given in your article, which, in Ashley, denotes a knot that is mainly of a decorative value only, is not fair. The "Mirrored" bowline is a fine knot, very easy to understand, very easy to tie, stable, secure, non jamming  - from the Double collar ( = two collars ) + Double nipping turn bowlines we have, iI think it t is one of the best.
   
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Festy on July 24, 2013, 09:17:54 PM
Would it be fair to say then, at least from how I understand the paper, that the standard bowline is to be avoided in life/injury threatening applications, and is actually inferior to the 'cowboy' bowline?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on July 25, 2013, 01:28:34 AM
I am also intending to include another obvious simple lock - that being a strangled double overhand knot around the eye leg (its simple and it works).
I don't want to discount the fact that this would increase the bowline's security and make for an easily-inspected knot, but the backup double overhand knot around a leg might not be as secure in certain types of line as it might first appear as it lacks some structure to press firmly against to prevent springing open.

Similarly, when people try to make a double fisherman's knot less jam-prone by putting a reef knot in the center, it really reduces overall security.

(http://s1.postimg.org/1jghb5ejnv/double_fishermans_reef_knot.jpg)

It also may be a bit irritating to have a lump in the loop, especially in cases where the loop needs to be small.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 25, 2013, 11:31:50 AM
About the Reversed Water bowline / Reversed Clove hitch based bowline, Mark Gommers writes, in "Analysis of Bowlies"
" In this variation, the Clove hitch structure has been tied in reverse.The Clove hitch structure may be prone to jamming (testing required to confirm)."
   As shown also in (1), the Clove hitch may look a very simple, very weak hitch, but when tied around compressible materials, as the ropes are, it can clinch very hard, and jam. On the Contrary, the Girth hitch does not jam, so it is a preferable solution in all its uses : As "normal" or "reversed" nipping structure, in a "common" as well as in an "Eskimo" variation (2).

 
   I have tested this bowline a number of times, under moderate but cyclic loading, and I believe I can confirm Gommer s statement : Indeed, this reversed Clove hitch structure jams, and jams badly : Therefore, most probably, it is not suitable as nipping structure for a secure bowline that can be used by rescue workers and climbers.

    We may say that a Reversed Clove hitch works like a non-Reversed Constrictor - and jams for the same reason, at the same place : the "lower" collar, around the eye leg (3). Both hitch structures, when tied around the legs of the bight component, are too tight, so they not suitable as double nipping structures for the bowline, I believe. When we try to improve the security of the bowline, we are walking a fine line : We should use a more complex and a more tight structure, but not beyond some limits : a too complex, bulky and difficult to tie structure, and a too tight one, prone to jamming, should be avoided.
   (See the attached pictures)

1. http://igkt.net/sm/index.php?topic=4347.0 (http://igkt.net/sm/index.php?topic=4347.0)
2. http://igkt.net/sm/index.php?topic=4009.0 (http://igkt.net/sm/index.php?topic=4009.0)
 
   http://igkt.net/sm/index.php?topic=4009.msg26872#msg26872 (http://igkt.net/sm/index.php?topic=4009.msg26872#msg26872)
3. http://igkt.net/sm/index.php?topic=4507.0 (http://igkt.net/sm/index.php?topic=4507.0)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on July 25, 2013, 03:12:28 PM
When we try to improve the security of the bowline, we are walking a fine line 

My point has always been it's a matter of finding the right balance between improving security and overly compromising any of the good traits present in ABoK #1010 - simplicity, quickness and ease of tying/untying, PET, TIB ...etc. The multiple-loop Tresse structure intrigues me as it appears to hold that promise.     
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 26, 2013, 01:21:06 AM
Hi alpineer,

Have you got any high quality images of your 'Tresse' structure?

If yes, can I use them (copyright and royalty free) in the paper?

And - I would need some technical content (a few paragraphs) to explain and compare/contrast it with #1010.

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 26, 2013, 01:31:57 AM
Hello SS369,

To answer your question, yes - I would be happy to release the 'Analysis of Bowlines' paper to the IGKT.

This would free me up as I am soon to run out of time (unfortunately, I have to work to earn a living and survive). Normally, this time of year is my busiest (work) period but there has been an economic downturn which has slowed me down too (worrying). Whilst I don't have a particular end date in mind per se - each day I spend working on knotty stuff is a day less spent on securing my work / income future.

I feel I have set a reasonable baseline for others to continue this work...

My preference is to upload the source document (which is in Bill Gates Microsoft Office Word format ...'filename.doc' - not the newer 'filename.docx' format). Hopefully, there are a few people in the IGKT that use Microsoft Word software?

The source file is close to 50 MB in size.

One way to do this is for me to upload it to a free 'cloud' storage site such as 'Dropbox'. I could upload it to 'Dropbox' and share the file with a list of IGKT people.


Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on July 26, 2013, 03:26:03 AM
Hello Mark.

Thank you for your response to my inquiry.
I would be interested in being a recipient of the file when you're done with it.
I am not familiar with Dropbox, but if that is what it takes I'll learn about it.
As for the IGKT being the repository for it, I was just asking ahead of time about the possibility.

I think we can all understand the "unfortunate" need to earn a living. So, I would like to publicly thank you for investing so much of your time to this. I personally appreciate the work.

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on July 26, 2013, 05:35:52 AM
Hi alpineer,

Have you got any high quality images of your 'Tresse' structure?

If yes, can I use them (copyright and royalty free) in the paper?

And - I would need some technical content (a few paragraphs) to explain and compare/contrast it with #1010.

Mark

Hi Mark,
I'll be working on that over the weekend, and of course you may use any images (copyright and royalty free). I must say you've set a high standard with your images.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on July 26, 2013, 07:17:37 AM
I don't want to discount the fact that this would increase the bowline's security and make for an easily-inspected knot, but the backup double overhand knot around a leg might not be as secure in certain types of line as it might first appear as it lacks some structure to press firmly against to prevent springing open.
While one can read of some rockclimbers testifying
to the loosening of a strangle tie-off, such that
I've mused about suggesting a double strangle (as it
will get one full round turn clear of changing direction
in tucking back through the nub), a well-set strangle
should hold.  BUT, (1) it doesn't ensure that the bowline
doesn't itself loosen, all so well --it's not easy to tie
the strangle snug to the bowline, though one
can work it so by means of pulling on the collar, after
the knot is tied (but that will enlarge the eye)--;
and (2) if tied around an eye leg, it fills an area that
might not have much room (the small eye of the
climber's tie-in comes to mind) --in this case,
the tail can be pulled away and tied off to the
SPart.  (A point you make, too.)

Quote
Similarly, when people try to make a double fisherman's knot less jam-prone by putting a reef knot in the center, it really reduces overall security.
???
How can the (so-called) "square fisherman's" be even AS
insecure --let alone more so-- than the squaREef knot itself?!
(I do have some inclination to recommend that the center
knot be the thief, in thought that it will slip until
pulling those back-up "safeties" (i.e., the strangles)
into the nub and getting them greater security, thus;
one needs to have pretty evenly distanced back-ups
so they abut simultaneously the center knot.)


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on July 26, 2013, 07:27:35 AM
I am also intending to include another obvious simple lock - that being a strangled double overhand knot around the eye leg (its simple and it works).
Mark

One can simulate this sort of coiled/wrapped looking
with the tail, tucking back through the turNip for
the finish --the tail's wraps bind the (two, not just
one
eye legs) and it in turn is nipped-gripped by
the turNip, which is effectively a half-hitch in this
function.  --i.e., a sort of strangle knot wrought of
the two parts and not a single strand.  In some cases,
taking the tail back through its own wrapping makes
for the surest looking binding; but it might just run
out the central nipping loop (aka "turNip")  to be
roughly parallel-to/beside the SPart.

There are various ways to instantiate this tail-wrapping
tactic, wrapping away and reaching back to tuck,
or reaching and then wrapping back (much as though
tying a strangle).  The former might be best
with the tail tucking back through the wraps,
so that's the more difficult one to tie,
vs. reaching and wrapping back and simply tucking
through the turNip --unless you want to tuck
now back eyewards through those wraps (which
indeed looks good!).


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 26, 2013, 10:47:33 AM
One can simulate this sort of coiled/wrapped looking with the tail, tucking back through the turNip for the finish
There are various ways to instantiate this tail-wrapping tactic, wrapping away and reaching back to tuck, or reaching and then wrapping back (much as though tying a strangle). 

   All those things are more complex than any of the simple "locks" we have, to enhance the security re. slippage of the Tail Common bowline - and require a minimum understanding of how the bowline works in the first place, in order to be understood, and not just be tied by parroted tying methods. If one decides to spend some hour to study the bowline, he will not need any such naive lock, as a double or triple or quadruple Strangle on the eye or the Standing end...He will just tie a Janus bowline, for example : much easier, much faster, much simpler - one whole knot, not one compound knot formed by the addition of a naive (  half-clever" = dumb ) thing. on top of a marvellous ( ingenious ) thing !
 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on July 26, 2013, 05:04:35 PM
One can simulate this sort of coiled/wrapped looking with the tail, tucking back through the turNip for the finish
There are various ways to instantiate this tail-wrapping tactic, wrapping away and reaching back to tuck, or reaching and then wrapping back (much as though tying a strangle). 

   All those things are more complex than any of the simple "locks" we have,
to enhance the security re. slippage of the Tail Common bowline ...

I disagree : rather, this tail wrapping (a) is much like
the tying of the back-up strangle knot, but it takes
a different course in (a1) binding the eye legs together
--which effects the locking of the turNip-- and (a2)
incorporates the two parts vs. the single strand (but
the tyer need not consciously remark at this);
and (b) it isn't merely fighting "slippage of the tail,"
but is --as noted above-- securing the turNip against
its loosening --that is the important aspect!


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 26, 2013, 05:26:28 PM
 :)
this tail wrapping (a) is much like the tying of the back-up strangle knot, but it takes a different course in
(a1)  binding the eye legs together--which effects the locking of the turNip-- and
(a2)  incorporates the two parts vs. the single strand, and
  (b)  it isn't merely fighting "slippage of the tail," but is ...securing the turNip against its loosening
  a1, a2, b... I wonder how many letters one should had used, in order this "much like" becomes "like", and then "not like" and then "different", and then "much different" - because that is the real relation between the Janus-like lock, on the one hand, and the naive x-turn Strangled overhand knot lock around the eye leg or the Standing end, on the other = they are much different !
 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 28, 2013, 03:00:18 PM
   In a previous post (1) I had proposed that we should mention - indeed, we should emphasize - the fact that the Lehman s locked bowline is TIB - but I had not said the same thing for the slight variation of the Scott s locked bowline, shown in the same post, and suggested in (2). Why ? Simply because I had NOT noticed that till now !  :)   :)  I was so sure it offered a slight advantage over the original Scott s locked bowline (3), -due to the fact that the Tail is not forced to make a sharp turn around one rope diameter when it collars the rim of the nipping turn-, that I had not examined any further. As I had said many times, it should be expected that with  stiff ropes, such a sharp turn can work as a spring, and drag the Tail out of the main collar around the Standing end - or, in a less tightened knot, it can be left in place as an "eye wide open", around the nipping turn s rim. However, I had never seen, till now, that this slight variation offers another advantage - which might be considered as MUCH more important than the "no-sharp-turns" one that had made me tie it in the first place !  A locked safe bowline, which is also TI,. is a very versatile knot. We do not have sooo many, that we can ignore the ones we meet, by design or accidentally !
   ( I am very curious how the inventor of the Scott s locked bowline will respond to this property / advantage of his own knot !  :) )
1. http://igkt.net/sm/index.php?topic=4480.msg28525#msg28525 (http://igkt.net/sm/index.php?topic=4480.msg28525#msg28525) 
2. http://igkt.net/sm/index.php?topic=19.msg20616#msg20616 (http://igkt.net/sm/index.php?topic=19.msg20616#msg20616)
3. http://igkt.net/sm/index.php?topic=19.msg20538#msg20538 (http://igkt.net/sm/index.php?topic=19.msg20538#msg20538)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on July 28, 2013, 04:24:00 PM
Perhaps it is because the inventor/artificer/discoverer/conjuror, knotting adventurer  :) thought it self evident.

As for stout ropes resisting this particular "locking". I have not been able to fail it with any rope I have.

Attached is a picture of the single locked bowline tied using nearly 3/4 inch diameter, very old and recalcitrant "bullrope".
I dressed it, then tightened it using force on the loop with foot and hand on SP. The picture was taken after shaking and beating (while unattached to anything) and the knot exhibits no loosening. The parts working together keep it locked and I am sure that if the loads approximated the working strength of the rope it would hold through out the task.

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 28, 2013, 05:31:26 PM
   Perhaps it is because the inventor... thought it self evident.
   It is NEVER self evident to all people, the fact that a knot is TIB or not...I had not believed that the Eskimo double eye bowline on a bight would really be TIB, although they have told me so !  :)  Each inventor knows MUCH more than the user, so he should never suppose that something about his knot is self -evident ! I had discovered the TIB fact just a few hours ago, although I had tied the knot many times !  It had just never crossed my mind...and I believe that it will not cross the mind of most members, if the inventor think it is self-evident !
   So, now I believe the inventor will, at last, ask Mark Gommers to include in his " Analysis..."  this TIB version of his knot, and mention, emphatically, the fact that it is a TIB bowline... because he has NOT done it till now !  :)  ( I still see the first / old variation, with the sharp around-one-rope-diameter turn, in page 19. )   
   
   You suppose that the ( old variation of your knot ) will always be tightened, so it will be able to keep the around-one-rope-diameter "springy" turn around the rim of the nipping turn, in place. However, BEFORE this happens, and before it gets "locked", the knot will remain slag in this point. The "orange" rope I have used in my pictures is the Speleo 11mm from Edelweis (1), a not-so-stiff rope, which does not stretches - so it can not make the one-rope-diameter turn of the old variation and remain "closed", without a substantial pre-tightening of the knot. The same happens with my newer "orange" rope, a BEAL Pro-Canyon 10.7 mm. They are no Anaconda-like ropes, but I am no Hercules to pre-tighten them as hard as you do either !  :)

1. http://www.edelweiss-ropes.com/en/ropes/26-speleo-11-mm.html (http://www.edelweiss-ropes.com/en/ropes/26-speleo-11-mm.html)
2. http://bealplanet.com/sport/anglais/corde-procanyon.php (http://bealplanet.com/sport/anglais/corde-procanyon.php)
 
   
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on July 28, 2013, 05:51:52 PM
   Perhaps it is because the inventor... thought it self evident.
   It is NEVER self evident to all people, the fact that a knot is TIB or not...I had not believed that the Eskimo double eye bowline on a bight would really be TIB, although they have told me so !  :)  Each inventor knows MUCH more than the user, so he should never suppose that something about his knot is self -evident ! I had discovered the TIB fact just a few hours ago, although I had tied the knot many times !  It had just never crossed my mind...and I believe that it will not cross the mind of most members, if the inventor think it is self-evident !
   So, now I believe the inventor will, at last, ask Mark Gommers to include in his " Analysis..."  this TIB version of his knot, and mention, emphatically, the fact that it is a TIB bowline... because he has NOT done it till now !  :)  ( I still see the first / old variation, with the sharp around-one-rope-diameter turn, in page 19. )   
   
   You suppose that the ( old variation of your knot ) will always be tightened, so it will be able to keep the around-one-rope-diameter "springy" turn around the rim of the nipping turn, in place. However, BEFORE this happens, and before it gets "locked", the knot will remain slag in this point. The "orange" rope I have used in my pictures is the Speleo 11mm from Edelweis (1), a not-so-stiff rope, which does not stretches - so it can not make the one-rope-diameter turn of the old variation and remain "closed", without a substantial pre-tightening of the knot. The same happens with my newer "orange" rope, a BEAL Pro-Canyon 10.7 mm. They are no Anaconda-like ropes, but I am no Hercules to pre-tighten them as hard as you do either !  :)

1. http://www.edelweiss-ropes.com/en/ropes/26-speleo-11-mm.html (http://www.edelweiss-ropes.com/en/ropes/26-speleo-11-mm.html)
2. http://bealplanet.com/sport/anglais/corde-procanyon.php (http://bealplanet.com/sport/anglais/corde-procanyon.php)
 
 

Well, some of us (one) thought it was "self  evident" because the general contributors to the thread are so astute.  :)

Perhaps Mark will read this and determine that the other attributes are to be added to his paper.

This particular statement is troubling: "You suppose that the ( old variation of your knot ) will always be tightened, so it will be able to keep the around-one-rope-diameter "springy" turn around the rim of the nipping turn, in place."

First: The "old" version is the version I recommended. It is simple and efficient.
Second: I suppose that the person(s) tying this knot will become proficient at it with very few tries. They can tie a standard, baseline bowline, get it formed and dressed loosely and then reeve the tail into place. Then dress it as it needs as you would need to dress any knot. I don't presume that you can tie any knot loosely and it will self dress. Some do, some don't.

This locking happens to work, even with that "slag". So what does one do when they have unwanted slack?

I truly believe that you or anyone who can tie the 1010 bowline can tie this simple lock with your eyes closed and even dress it so you won't have to see it unclothed.  ;)


SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 28, 2013, 06:09:50 PM
First: The "old" version is the version I recommended. It is simple and efficient.
   Yes, but the working end turns around ONE rope diameter, the rim of the nipping turn. Not good.
   The "newer" version is EXACTLY as simple as the "old", EXACTLY as efficient as the "old", and...
   AND...
   AND, it is TIB !  :)
   
   See the attached picture, for the "old", non-TIB version, shown in Mark Gommers "Analysis...", p.19, and presented at :
http://igkt.net/sm/index.php?topic=19.msg20538#msg20538 (http://igkt.net/sm/index.php?topic=19.msg20538#msg20538)
   The "newer" TIB version is shown in previous posts, and in :
http://igkt.net/sm/index.php?topic=19.msg20616#msg20616 (http://igkt.net/sm/index.php?topic=19.msg20616#msg20616)
   Your reply to this "newer version" was / is at :
http://igkt.net/sm/index.php?topic=19.msg20633#msg20633 (http://igkt.net/sm/index.php?topic=19.msg20633#msg20633)
   ( just in case you have forgotten it... :) )
 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on July 28, 2013, 06:24:37 PM
First: The "old" version is the version I recommended. It is simple and efficient.
   Yes, but the working end turns around ONE rope diameter, the rim of the nipping turn. Not good.
   The "newer" version is EXACTLY as simple as the "old", EXACTLY as efficient as the "old", and...
   AND...
   AND, it is TIB !  :)
   
   See the attached picture, for the "old", non-TIB version, shown in Mark Gommers "Analysis...", p.19, and presented at :
http://igkt.net/sm/index.php?topic=19.msg20538#msg20538 (http://igkt.net/sm/index.php?topic=19.msg20538#msg20538)
   The "newer" TIB version is shown in previous posts, and in :
http://igkt.net/sm/index.php?topic=19.msg20616#msg20616 (http://igkt.net/sm/index.php?topic=19.msg20616#msg20616)
   Your reply to this "newer version" was / is at :
http://igkt.net/sm/index.php?topic=19.msg20633#msg20633 (http://igkt.net/sm/index.php?topic=19.msg20633#msg20633)
   ( just in case you have forgotten it... :) )

Yes it is good. It works and works very well. I think the one diameter turn in this regard is not only sufficient, it is efficient and perhaps even better than a two diameter turn. I wanted the sharp turn/bite to be there.

The "old" version PET TIB as well, I am just not ijn need of tying it that way for my own use. I see the interest, theoretically, but I doubt I will have a use for the TIB for this knot.

And I did forget. ;-))) Though I did not give that tie higher kudos.

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 28, 2013, 06:37:23 PM
This ... happens to work, even with that "slag". So what does one do when they have unwanted slack ?
   One makes the turns wider, so the working end encircles more rope diameters, and it is driven smoothly from one place to the next. Especially near the end of the line, at the Tail, where we can not force it to follow a sharp curve by a tensile forces coming from both ends / limbs. The same happens in the "End bound" solutions... However, there the turn encircles more rope diameters, so it will not have the tendency to remain slack, or spring out.
   Mark Gommers shows two bowlines, in p.17 and p.24 of "Analysis...", which suffer from the same disadvantage. On the contrary, the Lee s locked bowline has solved this problem, by the re-tucking of the Yosemite s Tail through both collars around the eye leg of the Standing Part.
   Personally, I will always prefer a compact, dense  knot, with no slag, where the segments of the rope fill the emty spce within the knot s nub as much as possible. Why ? Perhaps because of Horror Vacui : "Nature abhors Void "  :) . I do not say that such a knot will be more secure or stronger than a knot that is spatially extended, and/or some parts of which will remain slag all the time. We have seen that the "Mirrored" bowline should better not be dressed very tightly, because the deflexion point where the Standing end meets the first,  "higher" collar should not be able to harm the rope too much.
   A compact, dense knot is always easier to inspect, because any mistakenly placed segment will disturb the ordered, tight arrangement of the others, and will be spotted instantly, like a fly in the ointment. Also, it will not present a wide outline / cross section, so it will not run the danger to be caught up somewhere, as a spatially extended, loose knot can. An "eye wide open" can always be caught up in a protrusion, and drag the Tail along with it, out of the knot s nub. Perhaps I am exaggerating the dangers, but if we can as easily tie a similar, yet more compact knot without slag parts, why we will not do it ?   
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on July 28, 2013, 07:38:41 PM
The "old" version  is... TIB as well
Noope !  :)
When you hold the ends of the Standing Part and the Tail, and you untie / untangle the eyeknot, you are left with a nice overhand knot tied on your line : a reminder that the inventors offen IMAGINE things the users are not able to find !   :) :)

Well, it all depends on how well you untie it.  ::)

I end up with a nipping turn around the standing part.
Yes, sort of an overhand, yet knot.  ;)


SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 29, 2013, 04:14:47 PM
Re Analysis of Bowlines paper...

VER 2.1b has been uploaded (2.37 MB).

Several changes, including changing all of the figure numbers denoting each knot.

Change log:
[ ] foreword edited
[ ] TIB expanded upon (and small symbol added to denote if a particular bowline is TIB)
[ ] added some double eye bowlines
[ ] added an image of a closed helix
[ ] Improved 'Eskimo' bowline images
[ ] expanded on explanation of right hand versus left hand bowlines
[ ] improved a few images in general
[ ] improved explanation of what a 'parallel' bight is (versus a crossed bight) - also changed 'Myrtle' image on page 10
[ ] page 18 changed - shifted knots around (enhanced the Lehman locks and added strangled double overhand lock)
[ ] removed a few images - due to feedback suggesting they were redundant (the yosemite variations to variations)
[ ] enhanced water bowline image on page 22 (figure 21)
[ ] made space for new additions

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on July 29, 2013, 05:00:53 PM
Re Analysis of Bowlines paper...

VER 2.1b has been uploaded (2.37 MB).

Several changes, including changing all of the figure numbers denoting each knot.

Change log:
[ ] foreword edited
[ ] TIB expanded upon (and small symbol added to denote if a particular bowline is TIB)
[ ] added some double eye bowlines
[ ] added an image of a closed helix
[ ] Improved 'Eskimo' bowline images
[ ] expanded on explanation of right hand versus left hand bowlines
[ ] improved a few images in general
[ ] improved explanation of what a 'parallel' bight is (versus a crossed bight) - also changed 'Myrtle' image on page 10
[ ] page 18 changed - shifted knots around (enhanced the Lehman locks and added strangled double overhand lock)
[ ] removed a few images - due to feedback suggesting they were redundant (the yosemite variations to variations)
[ ] enhanced water bowline image on page 22 (figure 21)
[ ] made space for new additions

Mark
I think you've lost sight of your original objective.  Correct me if I'm wrong, but I don't think you have a problem with the security or stability of a Figure Eight Loop.

So if you find a loop with security and stability equal to or better than the Figure Eight Loop, you probably should be cutting the loops that go yet another layer/step beyond this which hurts rope consumption, adjustability, memorability and inspectability.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 29, 2013, 05:43:14 PM
   I think you've lost sight of your original objective.
...which was the examination of more secure forms of Bowlines  !  :)
   Which is the title ? " An analysis of Bowlines". Is it "An analysis of eyeknots " ?  Nooo !
   Are bowlines a special kind of eyeknots ? Yeees ! Why ? Because they are post-eye-tiable ( PET ), and they can be tied and untied very easily, in one stage, without requiring any knot that has to be tied on the Stranding Part BEFORE the tying of the eye, and/or requiring a knot that has to be untied AFTER the untying of the eye.
    Of course, some people, for unknown reasons, will never be able to understand the difference between a PET and a not-PET eyeknot... and they will keep claiming that it suffices to tie an overhand knot or a fig.8 knot on the Standing Part, and then attach the tail on this overhand knot or fig.8 knot, by another overhand knot or fig.8 knot, tied on the eye leg of the Tail this time... Ingenious, perhaps, yet inconvenient - to say the least. However, this naive idea will always seduce some people that can not understand what a bowline is - it is a sad fact of life with which we should learn to live... :)
   
 
 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on July 29, 2013, 06:20:58 PM
   I think you've lost sight of your original objective.
...which was the examination of more secure forms of Bowlines  !  :)
   Which is the title ? " An analysis of Bowlines". Is it "An analysis of eyeknots " ?  Nooo !
   Are bowlines a special kind of eyeknots ? Yeees ! Why ? Because they are post-eye-tiable ( PET ), and they can be tied and untied very easily, in one stage, without requiring any knot that has to be tied on the Stranding Part BEFORE the tying of the eye, and/or requiring a knot that has to be untied AFTER the untying of the eye.
Why are you hyperventilating over something I didn't address?  Did I say that the loop had to be something that required steps before passing the rope through an object?  NO (http://igkt.net/sm/index.php?topic=4480.msg28932#msg28932)!

Can you stay on topic, please?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: X1 on July 29, 2013, 07:44:29 PM
Why are you hyperventilating over something I didn't address?  Did I say that the loop had to be something that required steps before passing the rope through an object?  NO (http://igkt.net/sm/index.php?topic=4480.msg28932#msg28932)!

   "Required Steps", means no-thing - and it can used to imply, on purpose or not, erroneously nevertheless, that forming one or more nipping turns is, in fact, also a "Step", just as tying an overhand knot, or a fig.8 eye-knot ! We should always beware of the various tricks one would try to fabricate / trump up, in order to underestimate the PET characteristic of the bowlines, and with it, the bowlines themselves.
  "Before tying" should always be accompanied with "after untying" - because no knot required to be tied on the Standing part before the tying of the eye, also means no knot required to be untied after the untying of the eye. The later is what makes the bowline such a valuable mooring knot - because a "relic" knot, still tied on a line after the eye has been untied, is a dangerous thing. It can be caught up somewhere, and cause severe problems.
    Having said that, I agree that you have not said something about a non-PET loop - yet !  :)  Because by judging from hundreds upon hundreds of posts where you did, I reckon that, sooner or later you will do - and I have to be cautious about it ! Sooner or later, you will refer to the fake, so-called "Zeppelin loop", which does not work as a rope-made hinge, as the genuine Zeppelin knot, the Zeppelin bend. Of course, you had never, and, most probably, you will never refer to loops that ARE working like the Zeppelin bend ( and ARE PET as well ) (1), because then you will have to admit that the so-called "Zeppelin loop" is an imposter in the family of genuine Zeppelin-like knots !
   The sad thing is that you are always too quick to refer to your site, or to the lamentable one-liner Wikipedia article about the fake Zeppelin - which, in its turn, expectedly or not, refers to only ONE site - guess which !  :)  (2)) You had not made any comment about anything written in the "Analysis..." paper, you had not submitted any opinion about any of the many knots shown there - but you are worried that Gommers  lost his "original objective" (sic), which you suppose that you know better than him !
   Dozens of knots shown there, but you had not been able to find ONE good word about any of them?So many notions, definitions and explanations about the bowline family - but you have not been able to discover even ONE thing that is true, and on what you agree ! Of course, this should have been expected, because you do not behave now in any original way ! You did the same in the three hundreds of posts in the "Bowlines" thread - and I bet you will keep doing the same long after I will die, voluntarily drinking poison !  :) :) :)

1. http://igkt.net/sm/index.php?topic=4095 (http://igkt.net/sm/index.php?topic=4095).
2. http://en.wikipedia.org/wiki/Zeppelin_loop (http://en.wikipedia.org/wiki/Zeppelin_loop)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on July 29, 2013, 11:05:00 PM
Quote
Similarly, when people try to make a double fisherman's knot less jam-prone by putting a reef knot in the center, it really reduces overall security.
???
How can the (so-called) "square fisherman's" be even AS
insecure --let alone more so-- than the squaREef knot itself?!
I wasn't comparing the "square fisherman" to the reef knot.  I was comparing the "square fisherman" to a regular double fisherman's knot.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on July 30, 2013, 05:19:38 AM
Quote
Similarly, when people try to make a double fisherman's knot less jam-prone by putting a reef knot in the center, it really reduces overall security.
???
How can the (so-called) "square fisherman's" be even AS
insecure --let alone more so-- than the squaREef knot itself?!
I wasn't comparing the "square fisherman" to the reef knot.  I was comparing the "square fisherman" to a regular double fisherman's knot.
OOps, yes, --my misreading.   :-\

As I said, though, if one uses the thief knot vice square
in this compound structure, with appropriate setting,
then the slippage in the center knot will give some bit
of stopper-effect on the strangle knots to help keep them
tied --to some degree redressing the vulnerability you cite,
yet without the considerable tightening effect seen in
the grapevine bend.

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 30, 2013, 08:55:23 AM
last update for a while...

VER 2.1c

Change-log:
[ ] revised the Foreword - added new paragraph stating that the 'Analysis of Bowlines' paper has grown to be much more than just a simple search for a replacement for #1047
[ ] as per X1's suggestion, all figure numbers have been completely revised (now listed as 1a & 1b; then 2a & 2b, 3a & 3b, and so on...)
[ ] added further commentary/revision to the Carrick loop (which has a nipping turn as a key bowline component)
[ ] made a fundamental change to the notion of 'front view' versus 'rear view' - hopefully this will please a few knotting masters :)  Instead of stating that there is a 'front' and a 'rear', I have opted to use the terms 'detail view' and 'regular view'. The 'detail view' emphasizes the nipping turn. The 'regular view' shows the side most people are accustomed to seeing.
[ ] as per X1's suggestion, I have made an attempt to align all the 'call-out' boxes so its a little easier on the eye when reading.

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on August 03, 2013, 10:44:06 PM
Hello Mark,

Here are images of the Tresse Bowline which you requested. If you prefer a white background, I can do that. If you require full size images, that can be arranged.
I'm sending tech info via PM.

alpineer
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on August 03, 2013, 10:48:24 PM
And the Tresse Bowline on a Bight.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Stagehand on August 10, 2013, 09:22:32 PM
Hello Mark, Thank you for your work in industry and in the Guild.  Thanks for the opportunity to contribute.  I would like to limit my remarks on the Analysis of Bowlines to the section on the Carrick Loop, ABoK #1033.  I question the suggestion that the Carrick Loop, ABoK #1033, is based on the Carrick Bend, ABoK #1439.  The Carrick Loop, when loosely tied, can be pushed by the fingers into the outline of a carrick just as any partial carrick may take up the carrick resemblance.  This carrick in the Carrick Loop lacks the complete interweaving of the Carrick Mat or the Carrick Bend.  There are a number of such partial carrick knots.  The Reef Knot, the Thief Knot, the Granny Knot, the Sheet Bend, and the Bowline are a few notable examples.  Especially for the demanding purposes in your view, a more clear basis could be reserved.  As much as ABoK #1439 represents  a specific carrick, a true carrick, then it can be seen as the basis of the Knife Lanyard Knot, ABoK #787, and the Chinese Button Knot, ABoK #599.  A fixed loop with a complete, oblique carrick could also be similarly judged.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on August 13, 2013, 07:32:18 AM
I question the suggestion that the Carrick Loop, ABoK #1033,
is based on the Carrick Bend, ABoK #1439.

Agreed : this should be called the "carrick bowline",
leaving the name unfortunately chosen by Ashley
for a certain other eyeknot.

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knoeud on June 12, 2014, 10:48:20 AM
It has been a long time since the last update! Any news on this paper?

Also, I don't understand why Mark doesn't recommend the EBDB Bowline in this paper! I think EBDB is a very recommendable knot since:

*   It has exactly the same 3 rope system as in EBSB+Y
*   It has the two nipping turns which is historically known to make the knot much stronger and has always been recommended over the single bowline
*   It is much easier and faster to tie compared to the EBSB+Y (hard to pass the tail in both collar and binding loop in practice!)

Dan Lehman, any suggestion on comparing these two knots for climbing tie-in?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 14, 2014, 04:31:26 AM
... the EBDB Bowline
Whoa, that's one "B" Byond balance
(redundancy).   ;D

Quote
* It has the two nipping turns which is historically
 known to make the knot much stronger ...
Testing is, for what it's worth (not so much),
not quite this clear --and to a much less than
"much" degree.  The real appeal is its better
security vs. loosening (which itself might be
of a degree too small for full comfort --hence
my extension).

Quote
It is much easier and faster to tie compared to the EBSB+Y
(hard to pass the tail in both collar and binding loop in practice!
But you must understand that Mark is deeply
in luv with the "Y" bit --I think he probably Ys
his shoelaces!   ;D

Quote
Dan Lehman, any suggestion on comparing these two knots for climbing tie-in?
I'd go with the EBDB (albeit partly from pride,
not the best guide).  But I've seen that eyeknot
loosen, in some things, and more recently
taken an interest in the more complex, repetitive
knots such as the mirrored bowline --which can
be quite loose in setting but I think will just not
loosen further very easily.  Also, the essentially
double-eye knots --where there is a 2nd passing
of rope through the harness-- provide some good
assurance against (at least) unnoticed untying,
as there'd be a long tail flopping about.

Might be good to have more- & less-rope-efficient
tie-in methods just to put the knotting at two
different places along the rope.  Otherwise, there
might be a desire for a knot that works better in
the stiff, inflexible rope one can sometimes encounter
--and where tightening the EBDB isn't so easy.

BTW, here's one of my latest ideas:
take the tail of a fig.8 eyeknot --that knot
sometimes required by climbing gyms to be used--
and put in a bowline *guard* knot to it,
reeving the latter's tail through the former
and back through the central nip of the Bwl
(for that 3dia bulk).  I think that the fig.8 will be
less prone to jam, thus (esp. w/the tail reeving),
and the bowline can evaporate so far as safety
is concerned, leaving the 8 standing guard as req'd.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: enhaut on June 14, 2014, 01:00:03 PM
Quote
BTW, here's one of my latest ideas:
take the tail of a fig.8 eyeknot --that knot
sometimes required by climbing gyms to be used--
and put in a bowline *guard* knot to it,
reeving the latter's tail through the former
and back through the central nip of the Bwl
(for that 3dia bulk).
I would like to see this in a picture if it's possible.
ths
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on June 14, 2014, 07:19:25 PM
[...] I think EBDB is a very recommendable knot since:

*   It has exactly the same 3 rope system as in EBSB+Y
We really need to get away from appearance-based evaluations.  I just did a security test with the belly of an "End Bound Double Bowline" linked to a Water Bowline (http://notableknotindex.webs.com/waterbowline.html) in some bluewater II rope.  It didn't take much shaking for the bound end to spring out and become a regular, mediocre, old double bowline (http://notableknotindex.webs.com/doublebowline.html) which then proceeded to become entirely untied.

The simpler, more compact Water Bowline stayed in form for the duration of the test. 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Sweeney on June 15, 2014, 06:35:42 PM
I was at the National Waterways Museum today and not being busy I did some rough and ready testing of the slack security of a few bowlines. The rope was 10.5mm 'semi-static' climbing rope which is stiff and not something I would normally use. In each case I tried a vigorous shaking of the knot for 30 seconds and the results were:

Ordinary bowline (#1010) - fell apart before the 30 seconds were up.

Water bowline, girth hitch bowline, double bowline, end bound double bowline, Lees locked bowline :  all of these loosened considerably though in each case when force was applied (only a pull using hand and foot) they all gripped and none collapsed. However I would be reluctant to trust any of them in this rope unless under constant strain.

Scott's lock : this was a surprise in that it was tightened to the same degree as the others but showed no sign at all of loosening even after a second bout of shaking.

This was an idle moment test born out curiousity rather than serious study so please treat the results with scepticism as I know you all will - and bear in mind that all I was testing was slack security not holding power under load.  Nonetheless Scott's lock is something I will look at using to see how it performs in everyday situations with 'ordinary' rope and cordage (I don't do climbing).

Barry
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 15, 2014, 10:02:48 PM
   I did some rough and ready testing of the slack security...
   I tried a vigorous shaking of the knot for 30 seconds...

   I believe we should establish a few guidelines for such tests, otherwise we would not be able to compare and evaluate any results we may acquire from them. Anybody would be able to "shake" an eyeknot differently, and "see" different things - because, as we all know, most knot tyers wish so badly to "see" only what they had already convinced themselves they "know" ... :) A future situation, where we would have a few circumstantial, differently designed and performed, and subjectively evaluated "tests", can be worse from the present situation, where we have no tests at all !   

  1. What was "vigorously shaken" ? The Standing End only, or the whole eye-knot, the eye included ?
  2. Which was the angle between the eyelegs during the shaking ?
  3. Was the eye free to move/rotate around the wrapped object, or not ?
  4. Was the eyeknot pre-tensioned at the start of the shaking, and, if yes, to what degree ? Any shaking, however vigorous and prolonged, will not be able to loosen a very tight knot, of course - so we should not only certify that the compared eye-knots were tightened to the "same degree", but we should also decide/define this degree.
  5. An important element that should be always decided/defined, too, is the length of the Tail. I have seen that, during "shaking", the motion of the Tail influences the behaviour of the whole nub : a longer Tail, which is shaken along the rest of the knot, can help the nub remain more compact, for a longer time.     
   
  Also, we should describe the "shaking", with more precise terms. For example, we can specify the exact location of the point of the line, and the path and frequency of its repetitive movement, which induce this "shaking". I have seen that a "shaking" of the eye-knot by the Standing End, which involves short instances of pulling of this End, has a very different effect on the loosening of the nub, as it was anticipated.
   
   Having said that, I wish to make clear that I am delighted those "tests" involved some newer eyeknots, as the Scott s and the Lee s locked bowline ( re-tucked Yosemite bowline ). Although my "tests" on the same knots had not the same results  :), I am delighted when people decide to tie and try knots they were not aware of until recently. The history of knot tying had not started, and we should always remember that it had not ended, with the ABoK !  :)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on June 15, 2014, 10:15:44 PM
Scott's lock : this was a surprise in that it was tightened to the same degree as the others but showed no sign at all of loosening even after a second bout of shaking.

This was an idle moment test born out curiousity rather than serious study so please treat the results with scepticism as I know you all will - and bear in mind that all I was testing was slack security not holding power under load.  Nonetheless Scott's lock is something I will look at using to see how it performs in everyday situations with 'ordinary' rope and cordage (I don't do climbing).

Barry
I do like the slack shaking security of this variant, but I have had instances where the knot form capsized under heavy load, and have discussed the issue with Scott on this forum:

https://igkt.net/sm/index.php?topic=5995.msg40270#msg40270

It should be noted that many loops are more or less secure depending on the direction the loop is hanging (e.g. if the belly of the  loop is above or below the knot body).
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 16, 2014, 01:30:51 AM
Quote
I do like the slack shaking security of this variant, but I have had instances where the knot form capsized under heavy load, and have discussed the issue with Scott on this forum.

Yes, we did discuss this variant, your claims, and to date I have not been able to duplicate your findings without leaving the knot poorly dressed and loose. As such it is no different than any other poorly tightened/dressed eye knot. A competent knot tyer/user knows to set their knots well.

I have recently pulled a tractor out of a ditch using two of these, one on each end and suspect that I was dangerously close to an unsafe working load (sometimes you use things you have the best you can.). I am not recommending this to anyone. But, the loops did the task and untied without the use of tools. No capsizing, no difficulty untying.

Quote
It should be noted that many loops are more or less secure depending on the direction the loop is hanging (e.g. if the belly of the  loop is above or below the knot body).

Want to qualify or expand on the quoted statement a little more?

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on June 16, 2014, 01:49:22 AM
Quote
I do like the slack shaking security of this variant, but I have had instances where the knot form capsized under heavy load, and have discussed the issue with Scott on this forum.
Yes, we did discuss this variant, your claims, and to date I have not been able to duplicate your findings without leaving the knot poorly dressed and loose.
The most convenient way to observe the nature of the Scott's Lock Bowline capsizing event is to tie the knot in bungee or shock cord.  Elasticity seems to play a role.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 16, 2014, 05:52:09 AM
[...] I think EBDB is a very recommendable knot since:

*   It has exactly the same 3 rope system as in EBSB+Y
We really need to get away from appearance-based evaluations.
Where that appearance suffices, it's fine;
I take it that the reference is to the 3 diameters
stuffed through the central nipping loop (and
suggested to be indicative of better strength).

Quote
I just did a security test with the belly of an "End Bound Double Bowline" linked to a Water Bowline (http://notableknotindex.webs.com/waterbowline.html) in some Bluewater II rope.  It didn't take much shaking for the bound end to spring out and become a regular, mediocre, old double bowline (http://notableknotindex.webs.com/doublebowline.html) which then proceeded to become entirely untied.
Of course, the obvious takeaway from this
report is that you made a good effort to put
the former knot at its loosest, or are entirely
incompetent at tying (dressing & setting) it!

But if we are using rope that is relatively stiff
and resistant to bending (and worse, springy),
it is critical for the EBDB to be set tightly and
that might be difficult; if loosened, its turns
around other turns can all just expand --which
in contrast the *bights* (by which I mean
U-shaped not O-shaped) want to open like
scissors and that can be easily impeded,
with good effect for arresting further loosening.

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 16, 2014, 06:06:16 AM
Quote
BTW, here's one of my latest ideas:
take the tail of a fig.8 eyeknot --that knot
sometimes required by climbing gyms to be used--
and put in a bowline *guard* knot to it,
reeving the latter's tail through the former
and back through the central nip of the Bwl
(for that 3dia bulk).
I would like to see this in a picture if it's possible.
ths
It's possible, but there are many ways,
but I'm unsettled on what's preferable
--doing what I'll describe again, and which
should need no graphic, seems overly bulky
(and needing some good guidance on how
much working end to have, in anticipation
of what one will need to do with it!).

Tie a bowline with amply large eye,
in which to then tie a fig.8 eyeknot
(with/in the former's eye), set close to
the bowline.  Now, tuck the bowline's
tail through the fig.8 --try different ways.

Now, the above tying method was given just
for simple illustration --to get one to the result--;
for tying-in, one cannot practically tie in-the-bight
but must reeve the tail of the fig.8.  Doing this,
though, with ample tail, enables one to then
put in a bowline to *guard* the fig.8
(since the former is "PET"=post-eye-tiable).

What I'm likely to prefer is some (novel) "quick8"
first-formed eyeknot, which (naturally, being "quick")
is more easily done, and then casting the guard knot
and then re-tucking the tail.  All of which is to result
with a bunch of knotting that, even loose-ish, should
prevent the tail from working out of.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 16, 2014, 06:45:05 AM
   I did some rough and ready testing of the slack security...
   I tried a vigorous shaking of the knot for 30 seconds...

   I believe we should establish a few guidelines for such tests, otherwise we would not be able to compare and evaluate any results we may acquire from them. Anybody would be able to "shake" an eyeknot differently, and "see" different things - because, as we all know, most knot tyers wish so badly to "see" only what they had already convinced themselves they "know" ... :)
Oh, I assure you, I much wanted the EBDB to hold
that "Devil's material" small, hard-stranded,
slick, polypropylene cord that was sent to me
(in anger & disgust!) : when it didn't hold, on my
initial tying, I acknowledged only losing a battle
on account of lack of trying, and I re-tied, with
deliberately forceful setting --"THERE, take THAT,
ha!"  And it took it for a while, but only a short
while, and then . . . those turns around turns
--3dia each way, so nice-- all expanded.
(I might have uttered some curse, at that point.)

The same material, tied with a "Janus" bowline,
only worked loose-ish --the turNip expanded but
the "janus'd" bights tried and failed to open much
like scissors (instead of rotating), and more of a
workable knot remained.

But "horses for courses"; rockclimbing rope is not
so devilish --less slick, less springy, more compressible.
But one needs to set the EBDB's turns around
turns tight.  Those of the SPart will be heavily loaded
on a fall; but those that bind them (when slack),
of the tail, will be no tighter than manual setting,
and hence the key to untying.

Quote
A future situation, where we would have a few circumstantial, differently designed and performed, and subjectively evaluated "tests", can be worse from the present situation, where we have no tests at all !
It should not be bad but helpful, to some
degree, if the testing is well described --which
it seldom if ever is, alas.  (E.g., was Roo's rope
--Bluewater II-- new(ish)?  (All I have of that
brand is ancient and pretty darn intractable;
but I have some newer PMI "E-Z Flex" (which
is well contrasted with their regular which might
be aptly named "No-Flex"!   ;D  ) ) 

Quote
  1. What was "vigorously shaken" ? The Standing End only, or the whole eye-knot, the eye included ?
  2. Which was the angle between the eyelegs during the shaking ?
  3. Was the eye free to move/rotate around the wrapped object, or not ?
  4. Was the eyeknot pre-tensioned at the start of the shaking, and, if yes, to what degree ? Any shaking, however vigorous and prolonged, will not be able to loosen a very tight knot, of course - so we should not only certify that the compared eye-knots were tightened to the "same degree", but we should also decide/define this degree.
  5. An important element that should be always decided/defined, too, is the length of the Tail. I have seen that, during "shaking", the motion of the Tail influences the behaviour of the whole nub : a longer Tail, which is shaken along the rest of the knot, can help the nub remain more compact, for a longer time.     
   
  Also, we should describe the "shaking", with more precise terms. For example, we can specify the exact location of the point of the line, and the path and frequency of its repetitive movement, which induce this "shaking". I have seen that a "shaking" of the eye-knot by the Standing End, which involves short instances of pulling of this End, has a very different effect on the loosening of the nub, as it was anticipated.
Yes, if one grasps the eye and shakes,
there should be some compressive effects
that wouldn't come to the nub if the eye
were freely rotating around something.

But, in large measure, the tests are not needed
to exact some **degree** of security, but more
of a pass/fail check.  Even in the quite-different
material of that "devil's material", seeing the EBDB
loosen did give some useful information, a caution
to tying and so on.  (Maybe to use some further
extension, such as a 2nd collar & tuck.)


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knoeud on June 16, 2014, 02:27:18 PM
Some good discussions going on here! :)

I think the fact is there are too many parameters in each test so that  we cannot extend or generalize any results to other situations.

That being said, my main interest is rock climbing and the falling situations with the Bowline knot. So the rope is a dynamic rope with a diameter between 8.9 and 11.

 As I understand the knot world, two main concerns are security and strength of the knot. I have used a Yosemite bowline for more than a year, climbing 5 hours a week. No surprise until now. Then I have recently switched to double bowline to improve the strength. Next step was naturally the EBDB to theoretically improve the strength using the 3 diameter system, but also improve the security with a tucked tail. 

SO it seems folks here are more and less OK with the strength of these knot variations and most of the discussion is on its security (for example in a shaking situation etc.). Frankly for me I can just make an overhand knot for the tail to secure it. However, I am yet concerned to find a STRONG variation of all these bowline knots that is easy to tie and un-tie.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 16, 2014, 02:44:53 PM
Quote
The most convenient way to observe the nature of the Scott's Lock Bowline capsizing event is to tie the knot in bungee or shock cord.  Elasticity seems to play a role.

Really? I believe this is a bit of a stretch. (Not just a pun.)

So, to investigate this I took a 3/8" bungee cord, tied the knot, stretched it to the point of no longer stretching (maximum elongation) and photographed it at that point. What I found is: The nub of the knot formed as all the others have, a tad more in areas perhaps. (The tail end bent forward more within the collar.) But, certainly no capsizing.

It still performed admirably to resist ring loading, both at rest and at full tension.
It did not untie easily, but did without the use of tools.

In simple fairness, I tied a Fig.8 loop (an accepted tie in eye knot) and found that it deformed almost to the point of being unrecognizable. (Needed duck billed pliers to untie it.) This proves to me that not all knots are suitable for All materials. Perhaps that is what you've been trying to say?

IMO, you must not be tying it well, or are tying it to fail along the lines of your claim.

* Is anyone else having this challenge?

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 16, 2014, 03:02:42 PM
Some good discussions going on here! :)

I think the fact is there are too many parameters in each test so that  we cannot extend or generalize any results to other situations.

That being said, my main interest is rock climbing and the falling situations with the Bowline knot. So the rope is a dynamic rope with a diameter between 8.9 and 11.

 As I understand the knot world, two main concerns are security and strength of the knot. I have used a Yosemite bowline for more than a year, climbing 5 hours a week. No surprise until now. Then I have recently switched to double bowline to improve the strength. Next step was naturally the EBDB to theoretically improve the strength using the 3 diameter system, but also improve the security with a tucked tail. 

SO it seems folks here are more and less OK with the strength of these knot variations and most of the discussion is on its security (for example in a shaking situation etc.). Frankly for me I can just make an overhand knot for the tail to secure it. However, I am yet concerned to find a STRONG variation of all these bowline knots that is easy to tie and un-tie.

Good day knoeud.

I too climb as frequently as I can. (Not nearly as much as I would love to!)
So far, it has not been proven that increasing the diameters within the nipping area does indeed increase resistance to breaking, but I am willing to speculate that it might.
In regards to climbing, I don't believe that you are going to exceed the breaking strength of your rope unless it is too old, damaged or some other influencing condition has been met. That is for you determine. Given those detrimental circumstances, any tie in knot will place you in more jeopardy.

If you like the bowline for a tie in, want a simple affair that has increased security (and possibly increased breakage resistance), ring loaded security, and ease of untying, I recommend that you give a few or all of the variants in Mark's (or others offered in the Forum) paper a safe try and get a feel for which one you like.

I personally have adopted and use the simple locked bowline that I have offered in the thread of that name.

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knoeud on June 16, 2014, 03:47:26 PM
I recommend that you give a few or all of the variants in Mark's (or others offered in the Forum) paper a safe try and get a feel for which one you like.
Yep, I am doing this every other day! ;) which will simply determine which variation is a practical knot for me. However, I have developed some theoretical analysis of different knots over the years which I want to summarize in a bowline variation.

So far, it has not been proven that increasing the diameters within the nipping area does indeed increase resistance to breaking, but I am willing to speculate that it might.

I don't think any of our hypothesis will be proven any soon. However, I feel a stonger knot is the one with 
1.  with the least curvature (as has been mentioned in the documents), and less tight nip. As we speculate, the 3 rope diameter will do just that. SO I''ll want to have it.

2. Also I think it is not just the "the tighter the nip, the greater the chance the rope will break"
My hypothesis is that having the standing part out-side of a first loop will help to increase the strength. I haven't seen any documentation for this hypothesis. on this subject, the only close analysis I know of, appeared in "Knotting matters, vol. 7, page 3" regarding the outside curve of a Fig 8. I have attached a fig for clarity. The claim is that with outside curve of standing part (point x) for a fig 8, the knot is 15% stronger (limited test of course). So basically I think the same is true for a double bowline and may explain its strength. Therefore, I want the two loops too in my bowline knot.

3. The last concern is how to tuck the tail so that it is secure and also easy to tie.
I have no hypathesis on this one ;), so I will continue my tests. [remark: As of today, I and a group of people we climb with don't find the EBSB+Y very practical since the tail is not easy to pass through the both loops]


Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 16, 2014, 04:29:44 PM
Hello knoeud.

Since we are speculating, till further notice, I offer this. The simple locked bowline does indeed contain three diameters within the nipping area and so there is part of your search. The tail tucks easily and straight forward, easy to remember. Simple to do with your eyes closed even.

But, I have to wonder if the increased mass inside the nipping area allows too much rope movement and thus allows friction to build to a point where heat is substantially generated at extreme loadings. At lesser loads it may, and I believe it does, cause a cushioning as in the example of you've shown with respect to the Fig.8/Dbl Bowline.

As been said here in the Forum, "Any sufficiently complex tangle can resist untying, etc.) But at what cost in other effects.

So try a Dbl Bowline with a "simple lock" and see how that grabs your sensibilities. I suspect you'll find it more than robust enough and simple to boot.
I personally don't find it necessary for my climbing needs.

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knoeud on June 16, 2014, 05:46:19 PM
Hello knoeud.

Since we are speculating, till further notice, I offer this. The simple locked bowline does indeed contain three diameters within the nipping area and so there is part of your search. The tail tucks easily and straight forward, easy to remember. Simple to do with your eyes closed even.

But, I have to wonder if the increased mass inside the nipping area allows too much rope movement and thus allows friction to build to a point where heat is substantially generated at extreme loadings. At lesser loads it may, and I believe it does, cause a cushioning as in the example of you've shown with respect to the Fig.8/Dbl Bowline.

As been said here in the Forum, "Any sufficiently complex tangle can resist untying, etc.) But at what cost in other effects.

So try a Dbl Bowline with a "simple lock" and see how that grabs your sensibilities. I suspect you'll find it more than robust enough and simple to boot.
I personally don't find it necessary for my climbing needs.

SS

Thanks SS369, I have actually tested your DB version since by default all knots I test are DB ;), but I need to gather the feedback of my friends too, will post  a summary of feedbacks soon.

in a related speculation, I have also been trying this EBDB modification of mine which is not a Y but tucks the tail nicely. Don't know if anyone has reported or tested this modification. Suggestions are welcome.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 16, 2014, 06:12:09 PM
You're welcome knoeud.

I'll look for your feedback in the upcoming days.

I can't fault your knot's end result (takes a bit more fiddling to dress and tighten, but hey we're knot tyers, and maybe harder to check for a novice), but,  if you are comfortable with using it, just test it some more under all the scenarios you could possible encounter. Close to the ground! ;)

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 16, 2014, 08:56:24 PM
   knoed, do not ask a farmer which one of his cows is better !  :) The Scot s TIB bowline ( left- and right-handed, shown, side by side, at (1)), is a much better eye-knot than the simple Scot s locked bowline ( which has this ugly sharp curve at its second/lower collar ) - and it is also TIB ! When you can have a TIB eyeknot, which has each and every of the advantages of a not-TIB one, and can also be tied in-the-bight following an easy to remember and quick tying method, why you would prefer the not-TIB version ? If you take a walk at the TIB bowlines area of the KnotLand, you will see that there is no reason to return back !  :)

1.  http://igkt.net/sm/index.php?topic=4517.msg30269#msg30269
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 16, 2014, 09:58:46 PM
   knoed, do not ask a farmer which one of his cows is better !  :) The Scot s TIB bowline ( left- and right-handed, shown, side by side, at (1)), is a much better eye-knot than the simple Scot s locked bowline ( which has this ugly sharp curve at its second/lower collar ) - and it is also TIB ! When you can have a TIB eyeknot, which has each and every of the advantages of a not-TIB one, and can also be tied in-the-bight following an easy to remember and quick tying method, why you would prefer the not-TIB version ? If you take a walk at the TIB bowlines area of the KnotLand, you will see that there is no reason to return back !  :)

1.  http://igkt.net/sm/index.php?topic=4517.msg30269#msg30269

Uh oh, the Bovinator is striking again. :)

Quote
The Scot s TIB bowline ( left- and right-handed, shown, side by side, at (1)), is a much better eye-knot than the simple Scot s locked bowline ( which has this ugly sharp curve at its second/lower collar )
And what do you substantiate your claims that those are "much better"with? Put your life on a line use? Feeling?
Many knots have a sharp bend and so must be ugly as well.
If you are going to sell your cows, you'll have to do better.  ;)

Although being TIB is a good thing, it really has no use to the tie in procedure. PET is what is needed more so.
I am not claiming the simple locked bowline (the one I offered) to be the end all eye knot, but it is a simple locked version of the standard bowline. If the standard bowline works and someone would like a security enhancement that offers a resistance to ring loading as well, it fills the bill.

By all means test them all.

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 16, 2014, 10:23:12 PM
I don't think any of our hypothesis will be proven any soon. However, I feel a stonger knot is the one with 
1.  with the least curvature (as has been mentioned in the documents),
and less tight nip.
As we speculate, the 3 rope diameter will do just that. SO I''ll want to have it.
It depends how the 3 diameters are disposed;
one needs to examine the SPart when it's heavily
loaded, nevermind anything else.

Doing that with a fig.8 might lead one to question
the broad-turn=more-strength theory, as there often
isn't such a broad turn to be found; rather, IMO, there
is something to the constriction around the SPart of
the eye-legs' U-turns (collars).

First objection is re "strength" : ropes don't break at knots,
experience shows, so how can some supposed strength be
important?  (And I recall an observation by one mariner about
damage after a hurricane severely stirred up a marina of boats:
some lines were in fact broken, but not at the bowlines (or eye
splices) (so, likely cutting effects came into play).  (Strength is
especially not relevant for abseiling --and yet some do mention
it!)

Furthermore, one must ask What is *strength*?!
--what is measured by a slow-pull device?
--or by a drop test?
--or by cyclical loading until abrasion proves fatal?
My surmise is that the last condition can prove a bane
for some knots that win on the first : precisely because
their SPart curves gradually over longer distance and
so has more movement during loading, there is more
friction-generated degradation in cyclical loading,
and ... the test device is shown to be a poor model
of practical concerns.  NB!

Quote
2. Also ...
My hypothesis is that having the standing part out-side of a first loop
will help to increase the strength.
//
The claim is that with outside curve of standing part (point x) for a fig 8,
the knot is 15% stronger (limited test of course).
Because ... ?!

The image you show is one I regard as absurd :
a) the supposed "outside" for the dbl. bowline is hardly
that --the doubled loop lies adjacent to, not around--;
b) the fig.8 image is ridiculous --and, yes, so broadly
used (what does that say about the users, AND readers?!)--,
as round-crosSection material will not hold such a pictured,
on-top-outside-of orientation.

Rather, in a properly dressed fig.8 one has one of
the parallel/twin parts reaching to the axial end of the
knot and when loaded bearing against its twin, or the
other part reaching less far and pulling away from its
twin and bearing into other parts of the knot (and it
seems to make a broaded turn --but look closely!).
(Most presentations of this knot family don't even
recognize the difference (and leave ambiguous which
end is loaded).)

I'll have to check what KM#007 (or nearby) says and who ...,
but my best information comes from Canadian climber and
IGKT founding member Rob Chisnall, who by illustration DID
seem to recognize the real difference in loading (and of the
proper setting --which he nicely illustrated), and his assertion
from some limited testing was a difference of --MIND THE
UNITS : % POINTS, not %-- 10 %-pt.s e.g. 70% vs. 60%,
and that for the loading of the end reaching farther and
pressing into its twin (which loading, btw, makes the knot
body assume more of a 45-degree angle to the axis of
tension; the other loading makes it more parallel).

Lyon Equip. did testing with this recognition but not so
much smarts about it in setting --i.e., I would want to
haul hard on the tails to impart more curvature to the
bearing-into-them SParts, for when push comes to shove,
the load on such rope will be WAY more than my setting
and should well challenge the curvature-inducement.
Lyon found some benefit to the overhand by this orientation,
but not with the fig.8; IIRC, the fig.9 might've been
slightly favoring the other way (but much variance),
and the fig.10 was maybe back to this way?

AND, to this, Dave Merchant opined that these more
complex knots (8-9-10) suffered more from dynamic loading
than did the simple overhand, which he presumed was
from the movement of rope and friction.

Quote
... don't find the EBSB+Y very practical since the tail is not easy to pass through the both loops]
I think that having the minimal body and then
TWO extensions to it makes a tough knot to tie.
Prefer the dbl (or water) bowline with double collars
--"Janus'd".  The 2nd collar helps keep the eye leg up
snug to the body (the collar of the SPart should be
left not-so-snug, to not so bend it), and arrests the
tendency of any rope from this side to creep in;
and without this assisted loosening, the feed into
the knot of the SPart, w/o ally, doesn't go far in
loosening : the knot stays tied, to hold the next fall.
(But each fall does move some rope, and this is something
to examine with some test of repeated loadings.)

Re this last point --of an untightly gripped SPart enabling
repeated movement in heavy loading, consider another
of my ventures to getting a secure-in-kernmantle tie-in:
the locktight loop, in which a structure somewhat
like the (multiple) strangle knot grips very tightly,
BUT has a *back door* that remains loosenable (whew!).

Let's see if this URLink works, to this forum:
OK - original sketches to get us started:

(http://www.knotveryinteresting.co.uk/posts/Locktight-Loop-I.jpg) (http://www.knotveryinteresting.co.uk/posts/Locktight-Loop-II.jpg)

Russ
Understand that the exact number of overwraps is a matter
of judgement per circumstance, but these show reasonable
starting points.  Version II was hoped to be better with stiff
rope.  These knots are meant to be set TIGHT (in contrast to
the mirrored bowline which is shown too tightly set by Mark
--constraints of image space, I think--, and fares well enough
rather loose.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on June 17, 2014, 01:39:25 AM
The most convenient way to observe the nature of the Scott's Lock Bowline capsizing event is to tie the knot in bungee or shock cord.  Elasticity seems to play a role.
Here's are some pictures with the standing part shown (under tension) on the top of each picture.  The untensioned line is the free end.  Each picture shows a progressive step in the capsizing process.

UPDATE:  Loop snagging vulnerability found: https://igkt.net/sm/index.php?topic=6773.msg44594#msg44594

(update: a variant that fixes these issues:  http://notableknotindex.webs.com/monsoonbowline.html)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 17, 2014, 02:10:18 AM
ANY one of the many knots that have a sharp bend in its nub ( while it could well had avoided it ), is an ugly knot

  An nice example of such an ugly knot is offered by Dan Lehman in this very page : See the first/at the left of the two spring-based-shock-absorber-looking loops, shown in his recent post. ( By this, I do not wish to convey the false impression, that the second/at the right loop, is much prettier !  :) ).
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knoeud on June 17, 2014, 09:28:42 AM
It depends how the 3 diameters are disposed;
one needs to examine the SPart when it's heavily
loaded, nevermind anything else.
I agree.

Quote
Quote
2. Also ...
My hypothesis is that having the standing part out-side of a first loop
will help to increase the strength.
The image you show is one I regard as absurd :
My bad, the fig 8 is simply an illustration from KM007. Such a harsh statement towards the founding members of Knotting Matters Dan!!! ;)
Well an illustration is what it is "an illustration"!

the point is, Bill Marsh in his book "Modern Rope Techniques in Mountaineering" -
advises: ".....always ensure that the main rope lies on the outside of the first bend in the knot (see Point "X" in the diagram). If this is
on the inside, the knot is weakened." Alan WALBRIDGE has tested this for fig 8 and confirmed based on limited experience.

The interesting thing is that you never find a Fig8 (or other variations of it) in ABOK where the Spart is inside! Ashley has always managed to magically draw the Spart curve outside! in this world of internet this information has been lost and every other site and book illustrates this in a random in- or out- manner with no care!

I think the hypothesis holds for the bowline too.

Quote
I'll have to check what KM#007 (or nearby) says and who
Did you get one in its time? ;)


Quote
Quote
... don't find the EBSB+Y very practical since the tail is not easy to pass through the both loops]
Prefer the dbl (or water) bowline with double collars
--"Janus'd".  ... the knot stays tied, to hold the next fall.
(But each fall does move some rope, and this is something
to examine with some test of repeated loadings.)
As you know this is of major importance for sport climbing, which consists of repeated tries of the crux and thus Repeated falling and loadings!!

I will add the other knot in our climbing knots.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knoeud on June 17, 2014, 09:48:03 AM
Hey folks, anyone knows where Mark Gommers is??

I want to update his paper to include a summary of these discussions, so the pdf stays up to date!
I remember he provided the .doc at some point for people to update. anyone know where the source .doc is?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 18, 2014, 06:23:05 AM

The image you show is one I regard as absurd :
[and I explain in detail why!]
My bad, the fig 8 is simply an illustration from KM007.
Such a harsh statement towards the founding members of Knotting Matters Dan!!! ;)
Where is a founding member, here?

Quote
Well an illustration is what it is "an illustration"!
... of what?!  It's supposed to convey
information.  Please (re-)read my explanation
of my charge(s) --I give a rationale for the judgement.

Quote
the point is, Bill Marsh in his book "Modern Rope Techniques in Mountaineering" -
advises: ".....always ensure that the main rope lies on the outside of the first bend in the knot (see Point "X" in the diagram). If this is
on the inside, the knot is weakened."
To which I pointed out that this statement
and associated image are ambiguous; different
geometries can result if that illustrated structure
is loaded.  If some dressing is applied, well, then
please show me where this dressing has been
specified (and where "on the outside" lies, then)!
Point is : it is NOT.
How do you not understand this?

Quote
Alan WALBRIDGE has tested this for fig 8 and confirmed based on limited experience.
Which sadly leaves Alan as one who has just
glossed over the ambiguity w/o notice or comment.
My surmise, btw, is that the "on-the-outside" part
gets drawn more naturally than not into the spot
I explain as reaching less far and pulling away from
the twin part; it is thus the form/loading of the knot
that Chisnall found to be weaker (and Lyon found
to be insignificant --i.e., either way, roughly equal).

(Alan tested knots for me --one time--, and I'm grateful
for that, preserving the partially broken specimens for
continued reference/study.  The rope was 1/4" laid/twisted
nylon, and the breaks were in either 1 or 2 strands (I think
an eye splice --for getting rope strength-- broke in ONE;
usually, though, to Alan's remark in km007:03, it was
stronger knots breaking two, weaker one strand). )

Quote
The interesting thing is that you never find a Fig8 (or other variations of it) in ABOK where the Spart is inside! Ashley has always managed to magically draw the Spart curve outside! in this world of internet this information has been lost and every other site and book illustrates this in a random in- or out- manner with no care!
I think I see the problem now : you need to improve
your eyesight!   ::)
#531 (eyeknot) doesn't fit the image above,
and will more likely give the bears-against-twin
orientation I define, partially --kinda looks to be
what Dave Merchant suggested, which is awkward
to do (as it entails the twin parts crossing).
#1047 is more typical of the presentation of such
tie-with-a-bight knots : the SPart/end distinction
is left to the imagination!  His flat, unrealistic drawing
at least settles into a well-dressed final one, albeit
still w/o hint of SPart/end difference.  Tell me, of
this illustrated well-dressed knot, which part lies
"outside" ?!  That inner/outer relation simply
doesn't obtain!  One can see which reaches farther
along the axis of tension.  (And in many photos of
loaded fig.8s, one can see that this part is slack
and so must not be loaded.)
#1411 (end-2end knot) is misdrawn of upper ends
--the SPart should be shown going UNDER the tail--,
but the lower ends are clear enough and in that state
will set into the bears-against-twin orientation rec'd
by Chisnall.  MAYBE Alan got that, but it's not at all
a given from the darn-lame "flat" illustration so often
presented!

Quote
I think the hypothesis holds for the [double] bowline too.
I think it holds as well --not "also", but "no better
than"!   ;)

Quote
Quote
I'll have to check what KM#007 (or nearby) says and who
Did you get one in its time? ;)
Yep.

Quote
... don't find the EBSB+Y very practical since the tail is not easy to pass through the both loops]
As you know this is of major importance for sport climbing, which consists of repeated tries of the crux and thus Repeated falling and loadings!!
Forgetting the fundamental Rule of Climbing:
Don't Fall!
You can I think search and find "Lehman8" on this
site, which was my attempt to bring bowlinesque
push-the-collar-back easy untying to the fig.8 base
(for its security & strength).  IMO, the 8 might get much
strength from the bearing/gripping of the tightening
double collars and so my Lehman8 looses that, going
for the "bears-against-twin" cushioning.  At which
point I then bring up the point that all of the knots
are amply strong (as shown by historical usage).


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 18, 2014, 06:26:38 AM
The most convenient way to observe the nature of the Scott's Lock Bowline capsizing event is to tie the knot in bungee or shock cord.  Elasticity seems to play a role.
Here's are some pictures with the standing part shown on the top of each picture.
But there are TWO parts on top ... --which
is which?

It would help to have some words as to what
the images show, how it was got, et cetera.
(E.g., "This resulted from ring-loading.")

--dl*
====

ps : I will leave it to X. to say which is "pretty/ugly".
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 18, 2014, 06:31:51 AM
ANY one of the many knots that have a sharp bend in its nub ( while it could well had avoided it ), is an ugly knot
  A nice example of such an ugly knot is offered
by Dan Lehman in this very page : See the first/at
the left of the two spring-based-shock-absorber-looking loops,
shown in his recent post.
That sharp bend where the tail-side eyeleg
enters is worrying to firm/stiff rope, but a
help for flexible-but-springy rope such as
common laid polypropylene can be, as the
rope won't *flow* 'round this hard bend
and loosen, but will want to open it like
scissors but fail --i.e., the difference I told
above between the EBDB's round, 3dia.
turns and the Janus bowline's bights.

Quote
( By this, I do not wish to convey the false impression,
that the second/at the right loop, is much prettier !  :) ).
You wouldn't be, for it's true not false
--a beautiful knot!


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 18, 2014, 07:09:22 AM
That sharp bend ... is worrying to firm/stiff rope, but a help for flexible-but-springy rope

   I think that we should try to tie knots that can be tied, and be at least not-ugly ( if they are not pretty ), in any "ordinary" material.... Perhaps this is not but a hope, a wishful thinking, of somebody who believes that "knots" are mostly knotted structures, tied on materials, not knotted materials - i.e., that geometry is the most important property of any knot, not composition.
   
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 18, 2014, 07:14:55 AM
That sharp bend ... is worrying to firm/stiff rope, but a help for flexible-but-springy rope

   I think that we should try to tie knots that can be tied, and be at least not-ugly ( if they are not pretty ), in any "ordinary" material....
Beauty is in the eye of the beholder
(but then why are those curators filtering
all the new rubbish at us as *art*?!).
Spring PP rope is quite common.

 ;)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 18, 2014, 07:27:02 AM
   I think that we should try to tie knots that can be tied, and be at least not-ugly ( if they are not pretty ), in any "ordinary" material....

Spring PP rope is quite common.

   My English attempts are much worse / uglier than my knots !  :)
   Perhaps I should had written " in each and every "ordinary" material ". I mean, a knot should not be ugly if tied in any one of those materials. PP included...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knoeud on June 18, 2014, 10:20:00 AM
I think the hypothesis holds for the [double] bowline too.
I think it holds as well --not "also", but "no better
than"!   ;)
I'll keep this one :)
I need to check out those knots. a contrario, it suggests that only few drawings of Ashley don"t fit the absurd image, most do ;)

Playing with all these variations of bowline when climbing, I completely agree that only one modification to the original DB or B is good but more than that is just not very practical.

I cam up with this one the other day, which has the same 3 dia as EBDB and EBDB+Y. However, it secures the tail in the same move when we are making the 3 dia thanks to the collar. I have a good feeling about the overall structure. Dan what you think of this? (it is not a lee lock, but a DB with a new secured tail or say an EBDB where the turn is more secured by the collar)


Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 20, 2014, 06:45:43 AM
I need to check out those knots. a contrario, it suggests that only few drawings of Ashley don"t fit the absurd image, most do ;)
Not so fast : it suggests that there were
only a few drawings of the fig.8 and that
none that I found fits the absurd image.

Quote
Playing with all these variations of bowline when climbing, I completely agree that only one modification to the original DB or B is good but more than that is just not very practical.
I'm not sure what you're saying here,
but I'll agree that knot users in most applications
will prefer to have a lesser than greater set of knots
to know.  But there are differing demands and
circumstances, which might call upon different
knotty solutions, so we should explore ... .
AND we must hope to gain an understanding
of the knotting, so that we can *invent* what
we need, in uncommon cases.

Quote
I came up with this one the other day, which has the same 3 dia as EBDB and EBDB+Y. However, it secures the tail in the same move when we are making the 3 dia thanks to the collar. I have a good feeling about the overall structure. Dan what you think of this? (it is not a lee lock, but a DB with a new secured tail or say an EBDB where the turn is more secured by the collar)
The knot that you show omits the binding
of the extension (tail wrap) of the SPart,
so I think your knot is suspect in that regard.

Yes, I have oriented the tail of the EBDB to lie
sort of "within the collar", but I think I favored
it otherwise --maybe only as being easier tied?

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knoeud on June 20, 2014, 09:03:07 AM
Thanks Dan, preciate your insight.

I finally got a chance to do some limited tests on the knot I showed (which I refer as RDB in the table). I have summarized the results in the attached table.

Since my first concern is to replace the infamous fig8 with a variation of bowline, I compared the Fig8 vs RDB using two climbing cords of 4mm and 7 mm. The cords were Beal brand new, where 4mm has a breaking load of 400 daN (kg), and 7mm is at 1170 daN (kg). I used a pull mechanism with two identical ends, tying one knot at one end, and the other knot at the other end of the rope.

To my surprise in both ropes, the fig8 failed and not the RDB! the fig 8 fail was the classical one, where the standing part fails where it enters the knot. (repeated tests and changing the ends for these two knots gave same results. (My theory was that fig8 should win against any bowline variation, so I used all my new cords to retest and retest! at the end, I was like, oh man, a bowline variation may be stronger than fig8! (?) )

Next, I thought of comparing with EBSB+Y, which may in theory protect the tail better with the Y part. Tests performed using the 4mm rope, in each case the EBSB+Y failed and not the RDB. (as a side note, it is a very different situation when a bowline fails, since nothing of the knot is left behind, no structure. However, when a fig8 fails, half of its structure is still there!)

My resources are limited, so I will appreciate it if someone could test these results to a better extend and confirm or dismiss my observations.

Next, I would like to perform tests on RDB, EBDB, and Prohaska Bowline (Janus). I need to buy new rope! :)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 21, 2014, 05:26:13 AM
Since my first concern is to replace the infamous fig8 with a variation of bowline,
Please state your reasons --i.e., what is it
of the one knot that you sought improvements
for, and that the other might provide?  (There
are many differences, and not all of these might
be of issue.)

Quote
To my surprise in both ropes, the fig8 failed and not the RDB!
the fig 8 fail was the classical one,
Could you specify the precise form/dressing
by reference to an image --here's a clear one
with what I regard as (for a name) "the perfect
form" (in terms of dressing).  It is loaded via
the right end entering the knot, the left one
being tied off in a strangle knot to that.
(This might be the most common version, but
sometimes the strands of the eye legs take a
different path, with a subtle crossing.)

Quote
where the standing part fails where it enters the knot. (repeated tests and changing the ends for these two knots gave same results. (My theory was that fig8 should win against any bowline variation, so I used all my new cords to retest and retest! at the end, I was like, oh man, a bowline variation may be stronger than fig8! (?) )
Craig Connally asserted that he found his favored
Yosemite bowline stronger than a fig.8, and had some wierd
position that contrary test results weren't the right
way to compare  --huh?  In any case, when someone
gets the results they want, expect X. to offer the sage
circumspection to not bet the farm (or boat) on that!   ;D
But I take your feelings.

Tom Moyer once had such a result, in a single test; he also
had some test in his high-mod-cordage examination in which
his fig.8 eyeknots broke --ALL 5-- at >90% of his tested
rope strength
(nb: tested, not vendor-stated).
Now, there just isn't enough *room* >90% to make
a fuss over (unless you consider some angler's testing
of the Bimini twist in which --to his shock-- he got >100%
of his tested strength (and was honest enough to think
"this can't be right" and to re-test!)).

I will also recall that years ago, reporting to this forum,
a fellow was testing end-2-end knots by breaking line
with two such knots anchored by fig.8 eyeknots to some
tree & his truck : the eyeknots never broke!
--even vs. an end-2-end twin fig.8 knot which is essentially
the same thing (2 fig.8 eyeknots) !?

So, you had an intact broken fig.8 to examine?
(Any chance of photos?)
With knots testing, one might try marking the rope
pre-test (maybe after some loading, to set the knot)
in a couple places, and then see where those positions
lie in the broken knot.  (Having a photo at some state
of heavy loading, near-full stretch, to see positions
would be best, of course.)

Quote
Next, I thought of comparing with EBSB+Y, which may in theory protect the tail better with the Y part.
Why would one care about protecting the tail?
(--unless a woman walking certain parts of Europe.   ;) )


Quote
Next, I would like to perform tests on RDB, EBDB, and Prohaska Bowline (Janus). I need to buy new rope! :)
Realize that your testing is suspect in having
no good measure of force, just A-vs-B results,
and w/o a LOT of that, you can be too easily
misled.  (Suffice it to say that if you have good
results vs. a knot that is reasonably known to
be pretty consistently strong --yes, the 8--,
you can at least conclude that a victor over
that will have done well.  But there remains
the prudence of seeing strength as largely
irrelevant to rockclimbing : history just doesn't
show knots breaking.)

I'd rather see a more different knot tried,
such as the mirrored bowline, in which
I see the "difference" being multiplicity
of loaded parts coming out of the main
nub --vs. just the eye legs for above.

Also realize that results of DYNAMIC LOADING
might differ from what we're seeing here;
and that is more relevant to tie-in knots.
HERE, I wonder if the mirrored bowline offers
significant advantage for a test of, e.g.,
repeated "FF1" (fall-factor 1 : drop = length
of line in system) drops.  That might be a test
you and some friends could do, expecting to
see knot conditions on a couple-few drops
before there is a final one.  (Pick straws to
see which "friend" is dropped.  No, drop
something inanimate!  --or drop Xarax,
but at LEAST 20-25 times : use a good knot
and rope (maybe a zeppelin loop).)
 ;D
)


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 21, 2014, 03:20:59 PM
Quote
But there remains the prudence of seeing strength as largely irrelevant to rockclimbing : history just doesn't
show knots breaking.)

I agree with this comment from Dan.

Strength is irrelevant.

Security and stability are of far greater concern.

Case in point:
An offset overhand bend (aka offset water bend) is perfectly adequate as an end-to-end joining knot in preparation for performing an abseil descent where you want to retrieve the rope(s) post descent. The load is 1 person. In a worst case scenario - the load can be 2 persons (rescuer + patient both descending on a shared belay device). The knot will not fail - it never fails (unless human error causes it to 'fail'). And in my opinion, the so-called 'EDK' is actually the offset figure 8 bend. This is the unstable/insecure form that has caused fatalities (again - this is my theory - witness accounts are sketchy because the surviving party members are typically inexperienced and suffering from shock - and can only try to recollect what they think they witnessed).

I just dont understand why there is so much attention given to knot strength?

The ability of a knot to resist cyclic loading (aka 'slack shaking' as some term it) is paramount. Also, off-nominal loading profiles - ie the knot is loaded in a way that wasn't intended - is also something that the knot must must withstand.

Of course, my context herein is mountaineering / rock climbing / abseiling activities where human life is literally on-the-line. That is, knot failure would lead to death - so you have to choose knots that wont fail. And strength is irrelevant.

...

I'm getting ready to update my Bowline paper soon and will be calling for assistance from people such as Dan and Xarax and other notable IGKT members...

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 22, 2014, 06:01:33 AM
   Hi Mark. It has been a long time since your last appearance in the Forum. We are glad you are back ! 

   For what concerns me, I believe I should try to repeat a few things, and I will try to do this as concisely as I can.
 
   1.
   A "secure" bowline may include a double nipping structure ( = two nipping turns on the path off the Standing Part before/ante the eye ), or not - but, IMHO, it should also include a double collar structure ( = two collars, two 180-degrees U turns on the path of the Standing Part after/post the eye ). Most knot tyers - Ashley included - believe that, in order to secure the common, Standard bowline from the danger of any accidental slippage of the Tail End, the most simple and efficient way is to grip this End in more than one points along its path, by more than one nipping turns. The most well-known applications of this idea are the "Double bowline" ( two turns - based ) and the "Water bowline" ( Clove hitch-based ). Perhaps these knot tyers suppose that a double nipping loop becomes, somehow, tighter than a single one, so it grips the penetrating Tail End harder, so the friction forces becomes greater, and the Tail can not slip through the nub any more. I happen to disagree. The main function of a more complex nipping structure is to improve its stability, not its gripping power - because the greatest danger in a common bowline is that, under heavy loading, the nipping loop can "open up", and degenerate into an open helix. A well-balanced, more tightly closed around itself nipping structure, will not suffer from this danger. THAT is the main reason which may justify the use of a double nipping structure ( like a Clove hitch, a Girth hitch, a Pretzel hitch (= reversed Girth-hitch) or a Constrictor ). The hypothetical enhancement of the gripping power of those complex nipping loops on the Tail End has not been proved by any detailed experiment, as far as I know.
   Even if one has not made up his mind on this matter, I believe he should always classify the secure bowlines according to this fundamental distinction : The first class will include all the bowlines with a simple, single collar, and the second class will include all the bowlines with a more complex collar ( like a double or a braided one ). My opinion is that you should better re-organize the order of the presentation of the bowlines in "Analysis" according to this criterion.

   2.
   If we do decide that, in order to avoid any slippage of the Tail End, we also need a more complex collar structure, the simplest and easiest way to do this is to make the Standing Part follow a second U-turn, this time "upwards", by making it turn around an eye leg, and/or around the "lower" part of the rim of the nipping loop. The most well-known applications of this idea are  the many possible "Janus" bowlines, Standard or "Eskimo"-like ones.
   Now, we have seen that, when the Standing Part has made a second, "lower" U- turn, and it is oriented "upwards", towards the Standing End, it is a most easy and straightforward thing to re-tuck it through the first, "upper" collar - and that, when this happens, we may end up with a TIB bowline (1). Many such cases have been demonstrated, and the method those TIB bowlines can be tied in-the-bight has been described ( the "haltering" collar method ).
   What I came to believe this last year, is that, if we have already decided to use a second collar, =  if we have already made the Standing Part be re-oriented towards the Standing End, then to make it pass through the first, "upper" collar, too, is only a very small price we should pay, in order to acquire a TIB bowline. To me, it seems not-so-clever to lose the great versatility a TIB eyeknot can offer, for just an easy tuck less. Moreover, it turns out that many of those TIB bowlines can be tied by this "haltering" collar method in-the-bight even easier and quicker than in-the-end ! If the satuation allows it, (  and it allows it many times, when I do not have a closed ring, but a pole or a bollard, around the accessible end of which I can pass my eyeknot...), I always tie such a TIB bowline in-the-bight.
   Even if one anticipates he will never want or need to tie his eyeknot in-the-bight, I believe that he can not deny the fact that a TIB eyeknot is a more versatile knot than a non-TIB one - so I believe that you should better include more TIB bowlines in your collection. In particular, I believe that you should include the TIB variation of the Scot s locked bowline, the TIB variations of the "Janus" bowlines, like the Alpineer s bowline, and the very simple TIB variations of the Clove- and Girth-hitch based bowlines. (2)(3)(4)(5)

   3.
   Although we can only speculate about its value regarding security or strength, when the nipping loop of a bowline encircles three ( or more ) rope diameters it becomes noticeably rounder and wider - and I do not believe there is any reason a segment of the rope inside the nub that passes near the nipping loop, should not pass through it as well. On the contrary, I believe that such a wider nipping loop, at the very core of the eyeknot, distributes the tensile forces along a more extended area, and I presume that this can not be but beneficial to the overall security and strength of the knot.
   So, I believe that this should be a third characteristic according which you should re-organize the order of the bowlines you present in "Analysis".

   4.   
   Recently, I had tied and tried a new secure bowline, which obeys all the three criteria I have pointed out above : It is a double/two-collar one, a TIB one ( which can also be tied in-the-bight very easily and quickly ), and a wide-nipping turn-based one. I call it Ampersand bowline, from the shape of its collar structure (6). I have also found ( not immediately !  :) ) that the Ampersand bowline and the Scot s TIB bowline are re-arranged "reversed" eyeknots ( where, by "reversion," we mean swapping the Standing and the Tail Ends ). It had happened to me to tie and try dozens of "new" bowlines, simply by systematically exploiting all the available options, and then submitting the outcomes to all the tortures I could imagine...( although my work can not be compared to that of Alan Lee, who has proven to be such a prolific, indeed, knot tyer...). So, I believe I am not mistaken when I claim that the Ampersand bowline is a notable member of the family of the secure bowlines, and that it deserves a place in the "Analysis".
 
1.   http://igkt.net/sm/index.php?topic=4695.0
2.   http://igkt.net/sm/index.php?topic=4517.msg30269#msg30269
3.   http://igkt.net/sm/index.php?topic=4697.msg30344#msg30344
4.   http://igkt.net/sm/index.php?topic=4695.msg32103#msg32103
5.   http://igkt.net/sm/index.php?topic=4695.msg31708#msg31708
6.   http://igkt.net/sm/index.php?topic=4877.0
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: enhaut on June 22, 2014, 02:15:29 PM
This "Analysis" (in progress) is a formidable study, many thanks to Mark Gommers and his contributors. The service gived to the community is immense.
 IMHO,the only thing lacking in the document, is"exploded views" of the bowlines. Alan Lee in this forum present sometimes his creations is this manner, it's a great time saving learning tool.
 For many reasons the Xarax's ampersand bowline deserves to figure in the "Analysis". His overall security seems solid and one of them is the astute way to tie it the the bight.
 Let me tell you Xarax that I had to work hard to figure it out! I think I have found a way of presenting the tumbling over (the verb) part.
 I think some TIB bowlines must be presented in this study but IMHO the paramount quality of a useful bowline is the fact that it's Post Eye Tiable.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knoeud on June 23, 2014, 09:52:58 AM
... a test of, e.g.,
repeated "FF1" (fall-factor 1 : drop = length
of line in system) drops.  That might be a test
you and some friends could do, expecting to
see knot conditions on a couple-few drops
before there is a final one.  (Pick straws to
see which "friend" is dropped.  No, drop
something inanimate!  --or drop Xarax,
but at LEAST 20-25 times : use a good knot
and rope (maybe a zeppelin loop).)
 ;D

back from an intensive 3 days of climbing and may I say hard fallings! I decided to perform your test Dan, and prepared a fall factor 1 situation (I had a back-up rope and a back-up harness in case anything go wrong. Don't try this unless you know what you are doing!).  The only small detail was then to do the 20 FF1  falls.  I couldn't find Xarax nearby, so I dropped me! scary  :o.  It was very fun in the beginning and natural, but after the 15th fall, you just don't want to deliberately let go and take a FF1 faaaall !! But we did it anyways ;)

I used a new 5m long, 10 mm dynamic climbing rope, which I tyed to an anchor point with a Janus bowline and tyed back to my first harness with a RDB (the close variation of EBDB that I am testing these days).

After 20 FF1 falls (see the photos), I could clearly observe that
* The knots kept their initial from (no dramatic change of form as it may happen with fig8).
* It was easy to untie them with tired climber' hands (after 20 climbs and falls)
* One other interesting observation was that the tail ending did not move on the RDB knot (not observable by eyes anyways). You can see this in the 3rd figure, where the U turn was left kind of loose and stayed like that after 20 falls. This point I will re-test with the pull system to the breaking point and take measures.
* the fact that in RDB the tail end was back inside the loop made a more compact knot (compared to the Janus) and enhanced the lead climbing experience (a matter of personal opinion I think).

I am done falling for now (pewh!), and going back to the pull system tests.

Appreciate any comments.

PS. from the last test results:
Quote

So, you had an intact broken fig.8 to examine?
(Any chance of photos?)

yes, I have to organize the photos and post a summary here very soon.

Quote

With knots testing, one might try marking the rope
pre-test (maybe after some loading, to set the knot)
in a couple places, and then see where those positions
lie in the broken knot.  (Having a photo at some state
of heavy loading, near-full stretch, to see positions
would be best, of course.)

I am organizing new experiments with 10mm climbing rope to perform a closer test. I will consider these points.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: zoranz on June 23, 2014, 05:17:13 PM
So, I believe I am not mistaken when I claim that the Ampersand bowline is a notable member of the family of the secure bowlines, and that it deserves a place in the "Analysis".
This is new lock, very interesting. For us non-experts in the world of knots it would be desirable that X presents end-loop in a loose form.
 
(http://igkt.net/sm/index.php?action=dlattach;topic=4877.0;attach=14769)

For now I can not switch to TIB variant. (Every journey begins with the first step.)

Best regards,
ZZ
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knoeud on June 25, 2014, 10:18:42 AM
As promised some pictures with markers to better understand the behavior of RDB knot.

This time no FF1 falling ;). I used a pull system, with a new 10 mm climbing rope. In the following figures, the initial placements of each part is marked in blue. The black arrows show the immobile parts and orange arrows show the movements appeared in the knot due to loading.

First and second figures show the knot at moderate loading. We see a great movement of the SPart that takes the Spart marker forward (couple of inches). Also small movement of the eye leg of the standing part due to the tightening of the upper nip (small orange arrow in figure 1).

We also see small movement of nip turns (due to the tightening effect) that leave the eye leg of the tail side and the tail-end turn (tail coming out of the nip) markers behind (small orange arrows in Figure 2).

The third figure shows the final state of the knot at very high loading (at which point the other end knot failed [EBSB+Y]).

I deliberately kept the tail-end turn of RDB loose to see the effect of the loading on it. We see no movement in the tail-ending based on the markers. This also confirms the hypothesis that the dressing of the tail-ending remains in its initial state from manual dressing. 

It is of interest to compare high-loading RDB state to Mark's figure from the high loading of the Bowline. Figure 4 shows this comparison. We see that at high loading the nip turns of the RDB keep their initial form and role, whereas the nip turn in the Bowline (on the right) transforms itself to a completely different form. Moreover, no upward displacement of the tail is observed for RDB which was the case for Bowline as pointed out by Mark (where the Spart leg of the nipping turn displaces the tail upwards).

----
P.S. In short: based on my FF1 fall tests, pull tests with 4mm, 7mm, and 10mm ropes, also my experience of lead climbing with this compact knot, its ease of tying, and ease of visual inspection, I have adopted this knot as my tie-in knot for everyday climbing. I will post new updates if everyday climbing with this knot changes any of my conclusions. It would be nice Mark if you could include this knot and a short summary of my observations in your Analysis. tnx.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 26, 2014, 02:37:13 AM
Quote
But there remains the prudence of seeing strength as largely irrelevant to rockclimbing : history just doesn't
show knots breaking.)

I agree with this comment from Dan.

Strength is irrelevant.
Well, we might take a half-step towards some
circumspection/qualification here : yes, the
great usage evidence doesn't point to there
being a problem re strength; perhaps, though,
we might learn something about the effects of
repetitions of "stronger"/"weaker" knots,
and maybe some need to look for strength
in special cases (secured tyrolean lines).

AND we might need to put in some caveat
re "repetitions" in regard to the sort of much
more extensive cyclic loading that can occur
in maritime towing?  (I think I've mostly only
some rumor of there being a concern e.g. with
heat build-up and internal chafing in esp. nylon
rope --of one case study in which a polyester
(3-strand? not sure) line was replaced with
like-sized nylon one, and the nylon failed.)

AND' we need to come to a better realization
of what we have actually been shown of
"strength" : both what sort of "strength" it is
--that of slow-pull to rupture, vs. cyclic loading--,
and how well whatever test method & knot tying
& material selection has revealed that!

So, to this, we have at least within the fairly
well documented history of rockclimbing and
some also caving & canyoneering evidence
only that knots aren't breaking.

Quote
And in my opinion, the so-called 'EDK' is actually the offset figure 8 bend. This is the unstable/insecure form that has caused fatalities (again --this is my theory-- witness accounts are sketchy because the surviving party members are typically inexperienced and suffering from shock - and can only try to recollect what they think they witnessed).
Whoa : it's fine & right that you deny
the "D" as attaching to the offset water knot,
but you can't go asserting that the "E" applies
as you wish!  As best I understand the history,
the moniker came from Yanks put off by Euros'
use of the OWK --I have some ca. 80s? Edelrid
brief rope-use pamphlet recommending this--
and labeling it in fear/speculation.  To which comes
the painful irony that one supposed improvement
--i.e., the offset fig.8-- is actually worse :
that would earn IT the "D", but hardly the "E".

Quote
I just dont understand why there is so much attention given to knot strength?
It's a simple datum (though see my note above
about what if anything some quoted test value
might mean!).

Quote
The ability of a knot to resist cyclic loading (aka 'slack shaking' as some term it) is paramount. Also, off-nominal loading profiles - ie the knot is loaded in a way that wasn't intended - is also something that the knot must must withstand.
Whoa, II : I don't equate shaking with cyclic
loading --the former doesn't entail much of
any load, just jostling (and this might be also
rubbing against a climber's body or the rock).


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 26, 2014, 02:48:45 AM
As promised some pictures with markers to better understand the behavior of RDB knot.
...
P.S. In short: based on my FF1 fall tests, pull tests with 4mm, 7mm, and 10mm ropes, also my experience of lead climbing with this compact knot, its ease of tying, and ease of visual inspection, I have adopted this knot as my tie-in knot for everyday climbing.
The obvious question is why "adopt this knot"
instead of the EBDB?!  It seems to me that
you have to lose attention to the key rationale
for the latter --i.e., of slack-security-- in order
to be then favoring the former (for supposed
easier? tying/untying).  The EBDB purposefully
binds the SPart with its tail wrap (and so gets
3 diameters within this wrap, which is a better
shape to bind against than two, in firm cordage),
which this RBD lacks, and to what end, so?


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 26, 2014, 05:45:00 AM
this compact knot, its ease of tying, and ease of visual inspection,
I have adopted this knot as my tie-in knot for everyday climbing.

   Compact, easy to tie and inspect, it is, indeed - but not much else, I am afraid. This "vertically" oriented round turn around the two rims of the double nipping loop does not look secure enough to my eye - except if you are prepared to accept a really looong tail - and do not forget to check its length, from time to time ! Those single turns, loaded from their one only end, unwind easier and sooner than you think. You should not suppose that the double nipping loop will be loaded ( and grip the round turn ) all the time ! A secure bowline should be able to remain in its initial state even if/after it is loaded unfavourably, and through any combination of its three limbs.

  When you pull the second leg of the collar... upwards, you see that this "round turn" rotates as a whole around its axis, and unwinds rather easily. This happens because the "two" points/segments of the tail where it is "nipped twice", move like one piece : if the first segment is forced to be set in motion towards one direction, the second can follow it and move towards the same direction, without having to overcome any additional friction force. This is the reason we never use a naked "round turn" as a final means to secure a tail...

   The other thing those parallel to the axis of loading turns may suffer, is that, squeezed by an external agent, they may clinch around themselves, and become difficult to untie. A corresponding bend, on which the one link is a double and the other a single round turn, was presented some time ago by JP, at (1)( with REAL tests, not just trials ). For a slightly different idea, where the round turn takes place before the collar ( so, it contributes much more to the stability and the integrity of the nipping structure ), see the 8 variations of the Link bowline, at (2). The single-nipping-loop version of what you show was shown by DDK, at (3).
   It seems to me that you were too fast to fall in love and adopt one bowline - which may be good for the bowline, but not for you... :)

1.  http://igkt.net/sm/index.php?topic=4150.15 
2.  http://igkt.net/sm/index.php?topic=4314.15
3.  http://igkt.net/sm/index.php?topic=19.msg20960#msg20960
     http://igkt.net/sm/index.php?topic=19.msg20961#msg20961

   P.S. I do not believe that this single round turn counts as a second collar ; it is a sort of an anchor, a way of securing the Tail End ( like the infamous not-so-clever overhand knot tied on the eye leg... ), but a second collar, it is not. That may be the main reason I do not believe this is a "secure" bowline, and I do not like it - as I had said many times, IMHO, a really "secure" bowline may include a double nipping structure, or not, but it should include a double collar structure. 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knoeud on June 26, 2014, 10:19:42 AM
Well I understand that everyone here has his strong opinion about one bowline or the other (mostly based on hypothesis of course).

For me, I am using them every day for real falls, so in the lack of consensus I performed my tests and presented the results in order to make up my mind about RDB.

However, I switch between different variations from time to time to make my opinion on each one in real life situations. suffice to say, It is not all about the theory, sometimes the simple fact that a knot is easier for my partner to check on the fly is a winner! (she can't always come and check my knot from behind and front views and see if the tail goes in all the places it should go! ;) )

I suggest to every climber to do the same and perform their trials to make up their mind about any variation presented in the Analysis. in this regard if you suggest other tests, I will try to perform (no more FF1 falling tho!)  ;)

The obvious question is why "adopt this knot"
instead of the EBDB?!
as you know I started with EBDB and am using it from time to time. but having a collar "protecting" the tail end (in RDB the tail turn is out of external reach compared to EBDB) and a collar pushing down against the tail loop and protecting it (especially when loaded) is something interesting. [those EBDB outside turns sometimes don't feel as solid as they should feel! ]

... It seems to me that
you have to lose attention to the key rationale
for the latter --i.e., of slack-security-- in order
to be then favoring the former

How to test the slack-security? how does this happen in rock climbing?

  [RDB is] Compact, easy to tie and inspect, it is, indeed
Yay ;)

but not much else, I am afraid. This "vertically" oriented round turn around the two rims of the double nipping loop does not look secure enough to my eye - except if you are prepared to accept a really looong tail
Well, I disagree. I have never observed any movement of the tail end. not in the fall tests (20 dynamic loadings), nor in the pull tests. Actually the fact that the tail is so immobile got me attracted at some point ;)

and do not forget to check its length, from time to time !
so you think there will be a tail displacement which is going to take the rope in. how can I test and  see this?

A secure bowline should be able to remain in its initial state even if/after it is loaded unfavourably, and through any combination of its three limbs.
This I agree :), I am going to test RDB, EBDB, and the &B in this regard.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 26, 2014, 11:21:19 AM
   Well I understand that everyone here has his strong opinion about one bowline or the other ( mostly based on hypothesis of course).

  If you are searching for proofs, the chances are you will find them in mathematics, not knotting !
  However, in order to be able to have opinions about one bowline, one should first acquire some knowledge about all bowlines - and this, unfortunately, requires some time, because there may be more bowlines than we think. We should start by tying and trying each and every bowline presented by "everyone" in this Forum, we should keep notes, and we better postpone our natural tendency to be seduced by the few things that had happened to us to meet first. KnotLand is not vast, but it is not sooo small either !

   
  For me, I am using them every day for real falls
  ...in real life situations.
     

   Those expressions you have chosen may be misunderstood : does "everyone" here uses the knots for imaginary purposes, in virtual life situations ?  :) :)
   For me, it is a much more demanding and difficult thing to advise somebody else which knot he should better use, than to use it myself ! My knots, and my life, are of no importance, in comparison to knots, and life - i.e., things that will still be here, looong after I will be theeere !     

   I performed my tests and presented the results in order to make up my mind about RDB.

   No, you performed no tests, you simply made some trials of the first bowline it had happened to you to fall in love with, and adopt - so you had already "made up your mind", or your heart, and you had no real need for any "results". In any experiment, the most critical property that separates the men / tests, from the boys / trials, is simply their number. We have too many circumstantial one-off reports on one-off knots, coming from one-off knot-tyers - but few people have the talent, the will, and the patience, to perform experiments - on the very same knots, over and over again ! If you are in such a hurry to jump into conclusions, and believe that you have discovered the lapis philosophorum overnight, is should be expected that you will not sacrifice your time in the temple of the real "tests" ! ( I have neither the talent, nor the patience - but I happen to know this !  :) )   
   Of course, "everyone" can "make up his mind" very easily and quickly, and tie a mediocre, or even a bad knot.  ( Contrary to what Mark Gommers says, I do not believe that the mediocre, or even all the bad knots, are going to be extinguished by natural selection... :)) If it will not kill him ( and, fortunately, mediocre or even bad knots seldom kill their user...), he can keep tying it all his life, and be satisfied he had found the Holy Grail. However, he will not have made anything more than this. I do hope that "everyone" here demands something more from a public discussion, something that will involve more than one knots, and more than one persons !
   There are not many reliable, repeatable, comparative, statistically controlled, etc. "tests" of knots, that is true - probably because nowadays knots do not have but a marginal use, in marginal fields of the modern world. However, there are some - and, searching in the web, you will find them, and see what we should mean by this "test" word... 

However, I switch between different variations from time to time to make my opinion on each one....
     

  Great ! Keep switching - because the glory of this bijou de fantaisie will be switched off by itself very soon, I can assure you...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 26, 2014, 11:47:01 AM
  I have never observed any movement of the tail end.
  Actually the fact that the tail is so immobile got me attracted at some point ;)

  Hmmm, I may say that a small movement of the Tail End proves that some of the tensile forces do reach the end of their line - because, otherwise, we may argue that the last tuck is redundant, and that there are parts of the rope that do not contribute to the whole. In fact, Alan Lee has seen something like this ( not exactly the same, but a similar thing ) in the case of the Alpineer s bowline (1) - and it is NOT a good sign ! If the knot locks prematurely, it is over-knotted - and it would not exploit the strength of the all the material it contains, so it will be less strong than another, equivalently complex knot.
   The last point where the slippage of the Tail End is confronted, is the last line of defence - and I had argued that the last line of defence should be the strongest. During REALLY heavy loading ( in your trials, you do not specify the load - you only describe it as "vey high"..), the Tail End SHOULD move !

1.  http://igkt.net/sm/index.php?topic=4851
 
   so you think there will be a tail displacement which is going to take the rope in. How can I test and  see this?

  By pulling the second leg of the collar, directly. So, it will be pulled by some noticeable and controllable amount of force - because, in really heavy loading, it will be pulled by some force, that is for sure ; the nipping loop(s) and the ( first and only, unfortunately ) collar can not absorb ALL the tensile forces. If they could, we would had no need for a "secure" bowline, ist it so ? 
  This round turn will revolve like a wheel, or it will jam - anything it will do, is not what we expect from the locking mechanism of a "secure" bowline to do !
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knoeud on June 26, 2014, 12:58:15 PM
Hey Xarax,

I agree with your point on tests and the lack of them actually!

We should admit that the knot tyers community is the least advanced in this regard.

1. I actually asked for anyone who would like to perform some well documented tests here
http://igkt.net/sm/index.php?topic=4934.0
Not even a Single response!!

2. This is nothing new! in KM12 page 17, John SMITH notices that lack of standard knot testing and suggests:
"May I express a thought, not yet matured into a suggestion, as
to a role the Guild might play? Should we not establish a series of
standard tests? Tests of strength, security, ease of opening, etc.,
could be performed in a standard range of materials, say 15
combinations of size and stuff."

That was in 1985, so 31 years later we still don't have this "series of standard tests"
Today we may have a chance to finally draft a standard test process? you can draft a first version Dan & Xarax ;)

3. I dont know how IGKT functions, but is there any chance igkt could finance such tests for a bowline study lets say?


Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 26, 2014, 02:17:05 PM
   I do not know of many other communities outside the professionals ( universities / industry / military ), which perform systematic tests, on anything ! Most of the time, competition is the name of the game, and it is competition what decides what lives and what dies. Here, we do not have knot-games - we have only knot-tyers-games, which are often not-games at all !  :(
   However, even in this Forum ( I mean, among arm-chair, mostly, knot tyers... :)), one can find decent test(s) :

   http://igkt.net/sm/index.php?topic=4150.msg25773#msg25773
   http://igkt.net/sm/index.php?topic=4150.msg26002#msg26002
   http://igkt.net/sm/index.php?topic=4150.msg26174#msg26174

   And we should not forget that knot tyers are everywhere - even up on the trees ! :
 
   http://www.paci.com.au/downloads_public/knots/14_Report_hitches_PBavaresco.pdf

   Knot-testing is the skeleton in our closet - I may be too pessimistic, but do not expect it will be incarnated any time soon...
   
   The only thing I can say, is that any journey starts from one single small step. START MEASURING every single property you can think of, of as many bowlines as you can, as many times as you can - and report your results. In time, the accumulation of all those data will pave the way for a more systematic work. The important thing is to start, and to measure !  :) 
   
   http://igkt.net/sm/index.php?topic=4150.msg26308#msg26308

   P.S. Myself, I was never able to imagine even one f... way to measure the un-tiability of a knot - probably because there are many ways to untie a knot, which involve this most complex tool we call " hand".
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 28, 2014, 12:58:05 PM
For us non-experts in the world of knots, it would be desirable that X presents end-loop in a loose form.

  I am not an "expert" on the world of knots either - and, frankly, I do not wish to become one of them !  :)
  I had decided to show the knots I happen to tie in a compact form, for a reason : in a loose form, what is shown is the topology of the knot ( which may be useful, indeed, if it serves as a 2D representation and a tying diagram - but this does not happen always : many knots are tied in a more easy and quick way, by other tying methods, involving a "haptic" and not a "visual" memory ). However, in such a loose form the geometry is lost - and it is the geometry, not the topology, what determines the basic structural properties of any knot. Two knots may have the same topology, but different geometry, as we have seen in the case of the "bistable knots" (1), and, recently ( and quite unexpectedly ) in the case of the Ampersand bowline and the Scott s TIB bowline. However, by a "loose form", you may mean just an "exploded form" - which is identical to the form of the tight, compact knot, when the diameter of the rope has been reduced. I admit that I would had shown such pictures, if it was easy to me to do it - , but, most importantly, if the pictures I show had attracted the interest of more than a handful of people... :)  I believe that those few members can "read" a picture which shows a simple knot, with some ease - and, in any case, easier than they can read a text, in hieroglyphs, which is supposed to describe a knot... :)
   See the attached picture, and the .km files, for a simplified representation of the Ampersand bowline, where I tried to keep a balance between the need to show the knot in a form resembling its actual geometry, on the one hand, and the need to present a stylized diagram of it, easy to memorize and remember, on the other. There are maaany ways to represent a knot in 2D - a more talented member may find a more useful way.
   I had tried to post an animation, in a .kma file, but the Forum does not allow it. Perhaps something can be done about it. In this "animation" file, one can watch the Working End as it "moves" from the Standing to the Tail End. The "speed" is adjustable, and one can even stop the animation in any frame he wishes, and then start again, from the same frame or from the beginning.   

1. http://igkt.net/sm/index.php?topic=4201
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 29, 2014, 02:39:04 AM
The obvious question is why "adopt this knot"
instead of the EBDB?!
as you know I started with EBDB and am using it from time to time.
but having a collar "protecting" the tail end
(in RDB the tail turn is out of external reach compared to EBDB)
and a collar pushing down against the tail loop and protecting it ...
One can make the EBDB so that the extension
(tail wrap) spirals within the collar vs outside of it
--just turn in vs. out, so to speak, the tail making
its additional tuck between tucked collar-legs vice
outside of the one.  (E.g., starting with the RDB
--helps if it's s short play rope--,
from your image above of the RDB (black rope),
just reeve the SPart through the tail-wrap --which
leaves the knot with all that it had before, plus the
binding of the SPart.)


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on May 30, 2015, 09:16:44 AM
Gathering momentum for a planned update to the Bowlines paper.

My objective is pure and simple - I want this to be the definitive resource for Bowlines and some other selected eye knots.

It will be freely available for download in the public domain.

It wont just be my viewpoint - I hope to receive contributions from interested IGKT forum members and anyone else from the broader community.

I would like to sort out some key knotting terminology - as this has been a constant source of contention - so it would be good to achieve wide agreement on terminology.

Credit will be given where it is known - in line with a section of the IGKT website where 'new' knots can be submitted for analysis and recognition (eg Mr Dahm's 'Gleipner').

I will sort out the details of the content and how it ought to structured - with input from others.

I have posted a few Sheet bend images to illustrate some of the key terms I will be using in the paper. I note the universal portrayal of the Sheet bend in a certain perspective (which I have labelled as 'front'). Despite my best efforts, I cant find a single image of a Sheet bend showing the 'rear' view. This leads me to ask the question 'why'? Why do knot authors insist on showing the Sheet bend from a certain perspective? I have also chosen the Sheet bend on account of Derek Smith's notion of the 'SB core' in all bowlines.

Mark Gommers
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on May 30, 2015, 10:19:24 AM
   the definitive resource for Bowlines and other eye knots.

   "and some other eyeknots", or " and all other eyeknots" ? I believe that "eyeknots", in general, is a HUGE field - the number of all conceivable / possible simple, stable and secure eyeknots ( loops ), which can be used as practical knots, is much greater than the number of end-to-end knots (bends), for example - which is already too big !   
   I think that a more feasible task will be to narrow the scope of the task, in some way, and present only those eyeknots which also  satisfy certain more restrictive criteria : for example, you could present only the PET, or even only the PET-2 loops, which are numerous, but not numberless...
   
   Derek Smith s ( and Ashley s, from whom he inherited it... ) notion of a Sheet bend core of the bowline, is plainly wrong, and for more than one reasons ! For example, what they see as a "half hitch", is a "nipping turn/loop". A half hitch is loaded mostly by its one limb, a nipping loop is loaded by both. They are mislead by the "looks", because they are only interested in skin-deep, superfluous "similarities", and they do not "see" the flow of forces within the segments of the rope. A knot is NOT its image - ( Ceci est n est pas une pipe !  :) ) 

   Your pictures are beautiful, although the colours pattern on the shield of the "yellow" rope is a little bit confusing, IMO. A monochrome yellow, or of any other colour, rope would allow the reader s eye to follow its path, and its path only, within the nub more easily.
   Also, I think that the loaded ends of a bend should better be presented "in-lined", and aligned to the symmetry axis of the frame of the picture - even if, in bends where where the Tail End(s) leave the nub from the one side, the other side looks a little empty. In eyeknots, the ideal would be continuations of Standing Ends bisecting the angle between the eyelegs - which angles should also remain the same throughout the collection ( 30 degrees will make an eye very narrow, very small or very elongated, 90 degrees will make it very wide, very big or very "fat", perhaps 60 degrees would be a good compromise . I think that if all eyes are shown with the same shape AND size, this will allow the reader to get some impression of the relative  size / volume/ of their nubs as well... ).
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on May 31, 2015, 09:08:46 AM
I received notification that a member from the IGKT forum actually found 2 websites where the Sheet Bend has been depicted in what I refer to its 'rear' view. Wow!

I must admit that my 'go-to' sources have always been more authoritative like Ashleys book of knots, and of course well known websites such as 'Notable Knots' and 'Animated knots'. I wonder why the owners/authors of these 2 high profile sites depict the Sheet Bend in the orientation I refer to as the 'front' side? I would be interested to learn about their reasoning...

I just did another google search for 'Sheet bend' and I can confirm that all the top 9 hits all portray the Sheet Bend in what I refer to as the 'front' orientation. The 10th hit was this site http://www.apparent-wind.com/knots/sheet-bend and it showed it from the opposite side.

Does anyone have (or can quote from) any authoritative books from well known knot authors (eg Chisnell, Budworth, etc) that also depict the Sheet bend from what I refer to as the 'rear' side?

The odd few that dont - I am not sure what to make of it !  Hmmmmm

EDIT:

Here's my thought process on this matter:
I have noted with some interest that none of the content providers/authors/photographers of the Sheet Bend provide a rationale for why they have chosen to portray their images of the Sheet bend from a certain perspective/aspect. I find this quite disconcerting and odd to say the least. I am one of those people that asks the question; 'Why?'  Why don't they provide a rationale/explanation for showing the Sheet Bend from one side or the other.... Could it be as simple as... they are just parroting what everyone else had done before them? Were they cognizant of the choice they made when they took the photo - that is, were they making a deliberate conscious choice to orient the knot structure in the way that they did? Or was it a random choice? Given the vast majority of images on the internet that show the Sheet Bend from one side rather than the other - perhaps this rules out randomness?

Can anyone shed some light on these thoughts?


I would also like to thank the individual who has thrown me into a bit of a tail spin and nose dive - as I really didn't know of the existence of the those websites! Just when you think you have enough sources to back up a theory - it all come tumbling down like a house of cards :)

Mark

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on May 31, 2015, 11:15:24 AM
While hunting around the web for images of Sheet Bends + books, I stumbled upon this 'Knotting Matter' issue #23 from 1988.
http://www.grumpyogre.com/dumpextras/othermags/IGKT/KM23.pdf

There is content about Scott's woven Bowline... at page 5.  Hmmm, it appears that Scott's discovery had already made an appearance in 'Graumont and Hensell's encyclopedia'.

Not sure what this means for Scott weave (ie woven Bowline)? Scott - can you check and confirm this please?

There is some other really interesting stuff in this edition of Knotting Matters - please take a moment to download and read it!

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on May 31, 2015, 12:52:42 PM
Thanks Xarax,

But my point was in relation to giving credit to Scott for the woven Bowline structure in the original Bowlines paper.

I specifically need to hear from Scott as to what his view/take is on this matter!

I also gave the URL/address for the whole of issue #23 from 1988.

What I am saying is that nobody had ever raised the issue with me - that maybe Scott's woven Bowline was already published nearly 3 decades ago - if I had known this - why would I have credited Scott with the discovery (does this make sense)? I just want to get the facts straight.

Again, I really need to hear from Scott on this matter :)

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on May 31, 2015, 01:33:46 PM
Hi Mark.

The picture at Pg 5 doesn't quite match up.
Actually the picture you've got doesn't either.

I've attached both your photo and one of my own for comparison.
And the borrowed bowline from the KM.

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on May 31, 2015, 02:41:51 PM
Hi Scott,

Not sure what to make of your reply and what the effective outcome is?

If i was thinking about the idea of the weave - that is, to weave the tail around the SPart a few times before feeding that tail back through the Nipping Turn - that idea was already discovered.

If I am understanding you properly, you are saying that your weave pattern varies (and is different) from the Knotting Matters structure - and this variation is deserving of it being a new/unique creation? Have I got that right? The idea of the weave - that is, the originality of the idea, therefore should be attributed to whom?

Could you straighten this out for me (no pun intended) in a definitive way please?

Mark

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on May 31, 2015, 08:46:36 PM
Hi Mark.

The idea can go to either. I think those in 1988 and myself thought of this (more recently)  independently.

I had thought to combine a braid and a bowline to try and marry the idea of the strength of a splice (sort of) along the path of the standing part to perhaps shed some tension into a non-straight part. It did make the bowline plenty secure and is no harder to tie than other modifications we've seen offered.

I don't know how to help you with the "originality of the idea". I had a creative moment that led me to what I posted.

Uniqueness? Well, it is a different knot. The Composite Bowline has extra "weaves" and follows a different path with the tail ending up on the outside.

Attribute the idea to the predecessor and if you end up using my offering you can say that it is along those lines. (No pun intended.)

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 01, 2015, 12:04:21 AM
While casting my net to increase the pool of knowledge to draw upon... I was about to purchase the
Encyclopedia Of Knots And Fancy Rope Work Hardcover  May 23, 2010
by Raoul Graumont (Author), John J. Hensel (Author)


  when I stumbled across the comment from Dan Lehman:

Quote
While I mostly concur in fellow IGKT member Joe Schmidbauer's review, I will emphasize that this large book is by no means helpful in learning how to use knots/rope. It contains many errors and usually is bereft of any guidance on WHY a certain knot is shown. Further, its images are often hard to discern.

2011 update: The more I've referred and looked into this book, the more disgusted I've become at how appallingly bad it is re any practical knotting. I leave my rating at Two Stars only because there seems to be some value to it asserted by decorative/fancy knot tyers, and I'm not interested in trying to assess that value (though I would ask about whether the accuracy or lack of is any different than the bad state it is for practical knots). Page after page, Plate after Plate of often bad/unclear photographs, one will be continually asking "Why is THIS supposed 'knot' presented?!" Seldom --SELDOM-- does the text provide anything helpful. And the supposed knots mostly exist only in the minds of the authors and these pages; many are quite comical, as are the names given to them. In sharp contrast, Ashley at least provides some information about most of what he presents, and his collection has knots that actually work.

At USD $59.28 + additional shipping costs to Australia, I am reconsidering my purchase - which is a shame because I thought it might be a valuable knotting resource to add to my collection.

I wanted (in part) to obtain more research material for insight into the originality of the idea of the weave pattern on the SPart of a Bowline before feeding the tail back through the nipping turn (+ any other historic info on Bowlines).

Also considering purchasing this book:
KNOTS AND SPLICES
Jan 1, 1957
by C.L. DAY

at USD $15.71 + shipping costs to Australia

Didn't see any reviews by Dan (yet).

EDIT

I have also added further commentary at reply #103 - re the Sheet Bend. I would appreciate some considered thought on this matter please.

Rebooting now... loading, please wait!

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Sweeney on June 01, 2015, 08:14:23 AM
The Graumont & Hensel book is comical in the practical knots part but I bought a paperback in the UK for about 8 GBP - it is a reprint of a scanned copy. At that price it is worth buying for some of the decorative stuff but mainly because the practical knots are a fascinating collection even if useless. There may even be a gem somewhere in there!

EDIT: I bought the book from bookdepository.com - they currently advertise the paperback at 23 GBP with free worldwide delivery (I paid 7.94 GBP with free delivery - inflation or has Dan inadvertantly made it popular!?).
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knot rigger on June 01, 2015, 06:12:51 PM
Agent_Smith

I believe you would be well served to pick up a copy of any book by C.L. Day.  I have Sailors' Knots (1935) as well as The Art of Knotting and Splicing (1947*), but not Knots and Splices, the one you mention.  As an author, he seems to me more like Ashley, and less like Graumont & Hensel in the sense that the knots he describes are practical, workable, well researched.  For instance, his treatment of the butterfly knot mentions both Burger from 1918 and Wright and Magowan from 1928, and he shows both their methods of tying.  His books cover a wide variety of practical knots, some fancy work, and all sorts of splicing, including wire rope and double braid.  Unlike Ashley, he depicts the knots with pictures rather than illustrations.  His pictures are clear and easy to follow, and he depicts tying methods, not just finished knots.  A point close to your heart, he depicts the sheet bend from both views (in both books!)  He also discusses and reports on knot breaking strength (doing some of his own testing, as well as reporting the results of others).  In his later work his discusses newer rope materials, and gives an in depth (although now somewhat dated) analysis of the pros and cons of each.  * I have the fourth edition of The Art of Knotting and Splicing  I imagine earlier editions would have less to say about synthetic ropes, or double braid splicing.

I have access to a copy of Graumont & Hensel's Encyclopedia and I will look up the "woven bowline" for you.  With a little luck, I may be able to provide you scanned copies of the relevant pages.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 02, 2015, 12:48:59 AM
I have just received a message from a member of the IGKT forum who is a professor of descriptive geometry.

I am making a special request to this person for an in depth analysis of why the majority of knot authors/photographers (in their published body of work) choose to portray the Sheet bend from a certain perspective. In addition, I am requesting analysis and sound reasoning of how to portray knot images in the 'Bowlines and other selected Eye knots paper'.

This paper will - for the first time - give a reasoned supporting explanation of why the knot images are portrayed in the manner shown.
As far as I know, no knot author (of a published body of work, eg in book form) has ever done this before (Okay - I'm sure some IGKT member will find a source to contradict me... please do!).

This explanation will be near the start of the paper - sort of setting the scene for whats to come.

I am no professor - and I'm not a professor of knots either - but I have the motivation to get the this work done and done right.

And having IGKT members involved with this project - it is by definition going to contain technical content that is exacting and perhaps divergent from the norm. But this is what I want to achieve - I want the paper to be technically correct, with all the latest theories revealed. Its all about attention to detail.

It is inevitable that there will be some who will disagree with the concepts in the paper - but there is an opportunity to make a contribution and have your viewpoint shared (made known). I see myself as the editor first and foremost, and as a contributor second.

Dan Lehman has been quite critical of other knot book authors - perhaps a good metric is to get the paper to a stage where Dan might give his nod of approval!!??????

I have included a sample image of what my vision is for the 'Bowlines and other selected Eye knots' paper in terms of showing their 'nipping structures'. I am working on photographing nipping structures..these are the only images I have thus far so don't get too critical as that would be premature.

Mark Gommers

Edited: Added clarity that I am referring to a published body of work (eg books, a website dedicated to knots and knotting, etc) and not random posts on a forum

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on June 02, 2015, 01:29:17 AM
This paper will - for the first time - give a reasoned supporting explanation of why the knot images are portrayed in the manner shown.
As far as I know, no knot author has ever done this before (Okay - I'm sure some IGKT member will find a source to contradict me... please do!).

You needn't look far:
http://igkt.net/sm/index.php?topic=4296.msg26773#msg26773
http://igkt.net/sm/index.php?topic=4296.msg26798#msg26798
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on June 02, 2015, 04:49:49 AM
This is to advise that I deleted my posts (replies to roo) - as I view them to be redundant...
And I have deleted my replies to tidy up the the thread, and since it could have been a private discussion.  Have a pleasant evening, Agent_Smith.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 02, 2015, 07:39:47 AM
Agent_Smith

I believe you would be well served to pick up a copy of any book by C.L. Day.  I have Sailors' Knots (1935) as well as The Art of Knotting and Splicing (1947*), but not Knots and Splices, the one you mention.
+10 !  --and I think that AKS(1947) is likely best
(fullest and most focused on knotting and latest!?)

I.p., Day puts a note of caution re Ashley's wanting to make
"bend" mean "end-2-end" --which it did not (and I prefer to
leave it not so).
Day has intelligence and rigor --more circumspect and less
*emotional* than his friend, Ashley (who is nonetheless
to be admired for his great efforts!).

Hansel & Gretel have been fairly assessed by me : reallly,
REALLY, it is incredible to see what they present !!!
Now, just as a hodgepodge mass of knotting to look over
and find things --sometimes the "finding" comes in looking
at an image and then doing some What if ... fiddling--,
it can be a sort of adventure.  But, for serious reference,
it is quite unreliable.  (Then, again, many are --so many
are echoes of others!)

Quote
  As an author, he seems to me more like Ashley,
and less like Graumont & Hensel
Goodness, G&H earn a flogging, the others some award
--it is not at all close.

Quote
[CLDay >>>>] practical, workable, well researched.  For instance, his treatment
of the butterfly knot mentions both Burger from 1918 and Wright and Magowan from 1928,
and he shows both their methods of tying.
A good example.  (In his AKS there is a good
bibliography, too.)


Quote
I have access to a copy of Graumont & Hensel's Encyclopedia and I will
look up the "woven bowline" for you.  With a little luck, I may be able
to provide you scanned copies of the relevant pages.
And maybe one can provide a conjurer to figure out
if any of what they present should be believed!


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 02, 2015, 09:10:40 AM
why the knot images are portrayed in the manner shown.

   Perhaps it is due only to our beloved sport - parroting  :). The same happens with the bowline, which is depicted in one of its two flat sides in 99% of the cases - although the other side reveals its details more unambiguously. Or it has something to do with the way brain conceives 3D shapes - which is also not an issue of descriptive geometry !
   I believe it would be an interesting problem for a psychologist, too : Show to 100 people, who had never seen a Sheet bend in their lives, how to tie it, let them tie it 100 times, and then show images of both sides of it, and ask them to choose which of the two represents better what they have in their mind.

P.S. Beautiful pictures !
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 03, 2015, 12:44:14 AM
Am working up a collection of images and concepts in preparation for the 'Bowlines and selected Eye knots' paper.

Sample concept image below...

I am in need of some high quality images or line drawings of the Lehman8. Can anyone assist please? I want to include high quality photos and technical discussion of the Lehman8 in the paper. I have some time today to take some photos.

Mark Gommers
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 03, 2015, 11:51:02 PM
With reference to the Bowline image on pg.4 of the "Analysis of Bowlines" paper...


1] "Eye-leg of the Tail side/Standing Part side" is bad grammar. "Tail-side Eye-Leg" would be a "technically" accurate term.  or, if you wish (but not I), "Tail-side Leg of the Eye".


2] I question whether it is necessary, even desirable, to include the term "Bight" with respect to describing Bowline anatomy.


3] "Collar", in my view, covers that part of the "Bight" all the way to it's closing at the Nipping Turn. Whereas "Bight" can be seen to overlap those parts of the Bowline described as "Tail" and also a portion of the Tail-side Eye-Leg. I see no ambiguity or conflicting of terms here as one normally uses them in specific contexts.


4] re: front/back side... The swapping of labels on Bowline images is entirely unwarranted IMO. However, which side of the knot more clearly shows detail is a matter separate from labeling. In your paper you show both sides, which is best. I think all of this points to Dan Lehman's desire to change how the Bowline is typically tied so that the historically labeled "back" side faces the tyer; and also to present the same face to the knot tyer as the Sheet Bend is typically tied. But label tampering is unnecessary. Show or describe the desired tying process, and if it catches on, you've accomplished what you hoped to.     


5] The location of the region of highest stress & strain seems inaccurate to me and should be focused on the nearby compression zone i.e. inner side of the cordage. This is what Dan Lehman's believes. I'm not sure if he claims authorship. I only claim support of it. Although compression occurs on this area of the rope, and I can see how that might reduce the threshold of the individual fibers to resist rupture, I believe this to be the area of highest tensile stress. Just don't ask me to prove it. ;D


6] I would like those curved lines showing the Collar and the connective Eye to be superimposed over the the rope and extended to show each term's limit without using the arrows. 





The essential elements of all Bowlines are it's Collar and it's Nipping Turn. But neither the Collar or the Nipping Turn can claim individually to be the essence of what a Bowline is. Both play equally important and inseparable symbiotic roles in defining a Bowline's essence.  They need each other to be linked in a special way to claim BowlinEssence (no more and no less than this). This is the functional mechanical essence of the Bowline. Although the Sheet Bend's functional essence differs from the Bowline's, they both share the same core geometry (CorEssence). The Core is where the interesting stuff happens, whereas the limbs provide the all important connection to the outside world.  The Core provides the foundation from which each knot's mechanical properties stem from. The CorEssence limits what may be considered as true Bowlines. For example, the Karash Loop might be described as a "Munter" Bowline. However, it's Munter element excludes it from being a true Bowline. The same reasoning can be applied to exclude Scott's Braided Bowline from the family of true Bowlines as it does not contain a proper Collar element. On the other hand, all multi-collar and all multi-nipping turn Bowlines are true Bowlines. 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 04, 2015, 12:13:23 AM

The essential elements of all Bowlines are it's Collar and it's Nipping Turn. But neither the Collar or the Nipping Turn can claim individually to be the essence of what a Bowline is. Both play equally important and inseparable symbiotic roles in defining a Bowline's essence.   The same reasoning can be applied to include Scott's Braided Bowline from the family of true Bowlines as it does contain a proper Collar element. On the other hand, all multi-collar and all multi-nipping turn Bowlines are true Bowlines.
;D

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 04, 2015, 12:17:15 AM
I saw what you did Super Snug. :)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 04, 2015, 12:27:19 AM
   The location of the region of highest stress & strain seems inaccurate to me, and should be focused on the nearby compression zone, i.e. inner side of the cordage.

   Why does a rope breaks, and where does this breakage occurs, is not a matter knot tyers can have an educated opinion...
 ( We can not even be sure that it is material-independent - does a rope made of many bundles of parallel fibres breaks in the same way and region with a rope of a few interweaved / braided fibres, or only one fibre ? )  It is a issue which should be studied by material scientists, with the help of the modern analytical tools ( finite elements analysis, computer simulations, etc. ), as well as of detailed experiments, performed under laboratory conditions.
   ( Personally, I would be surprized if it turns out that compression, and not tension, is the cause of the rope rupture. I do not see the kinds of deformation which would had been expected in regions of excessive compression. However, the presence of higher temperatures may indicate the presence of higher pressures, indeed - but it could also be the result of local excessive friction between the individual fibres in the core of the rope. In general, generation, flow or accumulation of heat, and the subsequent melting, perhaps play a more important role of what I used to believe.)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 04, 2015, 02:03:05 AM
alpineer,

I will try to capture all of these definitions of what constitutes a Bowline - but, it will have to withstand a barrage of opinions from a number of sources. Again, I just want to get this right - and I would like to facilitate this process in good faith (however, it will put me in the crosshairs of some individuals - but I see myself firstly as an editor and second as a contributor).

I am in favour of showing the various structures within a Bowline - using the arrows as I have done in my little teaser photos - showing the structures in enlarged form (sort of as 'callouts' in a document).

Doing so in this way is starting to lead me down a path of how to classify Bowlines based on their 'nipping structure' and 'collar-bight-capstan' structure. For example, #1013 has a double helix nipping structure, while #1010 has a single helix nipping structure.

With regard to the collar-bight structures, there may be one or more collars...

Some detailed thought will need to be given to this.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 04, 2015, 07:16:20 AM
Allow me to add to my earlier comments on the Bowline...

The Bowline is made up of two CorElemental linear forms - the Bight and the Turn. These forms have no BowlinEssence per se, but together they carry the potential to exhibit that quality. It is only when they become entangled with each other and cease to exist as separate geometrical entities they are able to function mechanically and exhibit Bowlinesque behavior. They then cease to be Bight and Turn and become Collar and Nipping Turn.   
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 04, 2015, 10:55:13 AM
The Lehman8... brought to you by your friendly agent smith  8)

Hope you like these Dan?

My question is, are these structures worthy of inclusion in the 'Bowlines and other selected Eye knots' paper? If not, why not (give sound reasons please).

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 04, 2015, 11:34:21 AM
Lehman8 images showing effects after loading.
Rope: Beal Joker dynamic rope  Website: http://bealplanet.com/sport/anglais/corde-joker.php

Tension force applied via AZTEK in 5:1 configuration - pulling to maximum (similar tension to a 'slackline').

Post loading: I initially thought the Lehman8 was jammed tight and would require tools to loosen. Thankfully, with only some relatively minor manipulation, I was able to loosen the structure by hand (no tools). The only way I could loosen the Lehman8 was by manipulation of the collar-capstan structure at the SPart side. I emphasise again that no tools were required - so by this definition I can say that the Lehman8 is jam proof up to the loading I applied.

Background story: For an image of an 'AZTEK' go here:  https://www.rockexotica.com/product/pulleys/aztek      I pulled as hard as I could by myself - until my eye sockets were bulging and veins were popping out, and at the same time, I cursed Dan Lehman under my breath. After exhausting my energy, I looked at the Lehman8 and thought...'Shit, its jammed'. Lawsuits against Dan were contemplated for compensation of my potentially destroyed Beal Joker dynamic rope. But then, I manipulated the 'collar-capstan' structure around the SPart and I worked it loose (with a sigh of relief).
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 04, 2015, 12:17:55 PM
Thankfully, with only some minor manipulation, I was able to loosen the structure by hand (no tools).

  Ouaou ! GREAT accomplishment !  :)  :)
  The great advantage of the bowlines is that they are easy to untie, not that they can be untied with no tools !
  I have told it time and again, and I will tell it once more : Beware of overhand loops and fig.8 loops tied on the Standing Part before the eye, and even in the Standing Part after the eye. It is such a simple rule of thumb !
  This infamous 19th century eyeknot is a perfect example of a NOT-bowline, hard to untie - so it would be helpful to include it in your collection, indeed ! ( as a negative example...)
  In (1), I have shown a bowline with an overhand shaped "8" collar structure - try it and see if it is easy to untie or not.

1.  http://igkt.net/sm/index.php?topic=5357.msg35854#msg35854

P.S. The last picture of the previous post, is telling about a common problem of those eyeknots based on interlocked overhand knots or fig.8 knots : they "close" prematurely, and so they leave some segments of their nubs rather loose = not utilised = redundant, even near their maximum loading... Same happens to the infamous so-called "Zeppelin loop", to which this ugly tangly has some intellectual affiliation... :)
Title: Re: Analysis of Bowlines
Post by: zoranz on June 04, 2015, 01:34:59 PM
The great advantage of the bowlines are that they are easy to untie, not that they can be untied with no tools!
Does it mean: "easy to untie" includes untying with tools?
(I always thought it was "easy" - if I use only my hands.)
Regards,
ZZ
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 04, 2015, 03:10:55 PM
   Noooo, of course not ! That was my point - easy to untie denotes a knot that is easy to untie using only one s fingers, and a minimum force. Most of eyeknots based on interlinked or interweaved overhand knots and fig.8 knots, especially when those knots are tied on the Standing Part before the eye ( where they are loaded by 100% and 50% of the total load by their two ends ), become difficult to untie after heavy loading. I believe that the Lehman8 is no exception to this.
   "Easy", means also quick - by submitting an almost jammed knot to ages of pushing and pulling, you will be able to untie it at the end - but you will never tie it again !  :)  :)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 05, 2015, 07:53:25 AM
Lehman8 images showing effects after loading.
Rope: Beal Joker dynamic rope  Website: http://bealplanet.com/sport/anglais/corde-joker.php

Tension force applied via AZTEK in 5:1 configuration - pulling to maximum (similar tension to a 'slackline').

Post loading: I initially thought the Lehman8 was jammed tight and would require tools to loosen. Thankfully, with only some relatively minor manipulation, I was able to loosen the structure by hand (no tools). The only way I could loosen the Lehman8 was by manipulation of the collar-capstan structure at the SPart side. I emphasise again that no tools were required - so by this definition I can say that the Lehman8 is jam proof up to the loading I applied.

Background story: For an image of an 'AZTEK' go here:  https://www.rockexotica.com/product/pulleys/aztek      I pulled as hard as I could by myself - until my eye sockets were bulging and veins were popping out, and at the same time, I cursed Dan Lehman under my breath. After exhausting my energy, I looked at the Lehman8 and thought...'Shit, its jammed'. Lawsuits against Dan were contemplated for compensation of my potentially destroyed Beal Joker dynamic rope. But then, I manipulated the 'collar-capstan' structure around the SPart and I worked it loose (with a sigh of relief).

Dan would defend against such libelous litigation by pointing
out how inadequate the setting of the knot was : so loose,
that embedded overhand component is --just as one can fault
the setting for those supposed discriminating tests of inner vs outer
S.Parts of fig.8 knots.  One must ensure that the "padding"
against which the S.Part will bear cannot so easily be pushed aside!
(And, yes, this raises the question of available setting for what sizes
of rope : will manual force be inadequate per individual and increased
rope sizes/stiffness (should be so)?)  In the materials of interest
to Agent_Smith's efforts, one ought to be able to set the knot well.
(And a key aspect re jamming is that the overhand is oriented
and loaded so that it should not become jammed; the fig.8 is
hoped to stay reasonably easily/forcibly able-to-be-untied by virture
of the part of the overhand that spreads the collar.)


But if one is unsure of a knot's behavior, then going gradually on
the test-loading is wise, lest you create a rock.


--dl*
====

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 05, 2015, 08:49:53 AM
   how inadequate the setting of the knot was

   Aha ! I now see ! It was the setting s fault !  :) :) :)
   Oh, my KnotGod ! Why you made them ( the knots ) with Your "good", right (?) hand, and us ( the knot-tyers ) with the other ?  :) :) It was only the "setting"(sic) of this ugly tangly, which jams, that was "inadequate"(sic) - everything else is fine ! 


Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alanleeknots on June 05, 2015, 09:15:43 AM
Hi All,
        Here are the some of my knots included Xarax version that I like it my self, these are the best amongst all that I have, Some are
        convoluted and some are not too bad. anyway they are valid knots.
        All of these knots are well secure and compact, can support heavy load, easy to untie after heavy loading.
        So far I only tested all these knots just little more then few time,anyone in this forum have interest in testing these knots,
        you are well come, for now just a rough idea what these knots can do. I will do more test in the future.

        Mark, here are the knots, see if you can find anything you like.

        謝謝 alan lee
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alanleeknots on June 05, 2015, 09:19:11 AM
more knots.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alanleeknots on June 05, 2015, 09:21:30 AM
more knots.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alanleeknots on June 05, 2015, 09:50:10 AM
more knots.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 05, 2015, 10:58:37 AM
Thanks Alan - a mind boggling collection of knots!

You have given me a lot of work to do...

I am going to have to do special index finger exercises to get it into shape for shooting numerous photos with my camera. I am glad we are in the digital age - I remember growing up with traditional film cameras and having to send it off to Kodak to get developed and not knowing the results (not to mention the cost of developing and printing photos).

I will be away for a few days and will not have internet access (June 06-08).

I just hope that I can do justice to your good work by providing high quality images...

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 05, 2015, 01:30:13 PM
   Personally, I like two more variations of the Lee s Eskimo 8 bowline, shown at the attached pictures.
   Beautiful knots !
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 05, 2015, 08:06:19 PM
(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=18234;image)

The poor knot tyers known as climbers use this knot as a harness tie-in. They call it a re-traced or re-threaded bowline for what should be obvious reasons - although my preferred term for knots tied in this manner is "twinned".
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 05, 2015, 08:22:38 PM
   I am impressed !  :) The climbers know ABoK#1080 ? Ouaou ! THAT is why they manage to remain alive !  :) :) :)
   ( alpineer, I believe you could had found a better joke...)

   P.S. However, I would like to learn how they tie it - do they tie it in-the-end, or in-the-bight ? And, if they tie it in-the-bight, which of the many methods they choose to follow ? Tying it in-the-end, is conceptually simpler, and can be done almost blindly - on the other hand, tying the ABoK#1080 in the bight and then retucking the tail ( in order to achieve a wider, 3-rope-diameters nipping loop - if they do that retucking ) is quicker ! I am interested in learning what do knot users prefer, a simpler or a quicker method ?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 05, 2015, 10:01:40 PM
   I am impressed !  :) The climbers know ABoK#1080 ? Ouaou ! THAT is why they manage to remain alive !  :) :) :)
   ( alpineer, I believe you could had found a better joke...)

   P.S. However, I would like to learn how they tie it - do they tie it in-the-end, or in-the-bight ? And, if they tie it in-the-bight, which of the many methods they choose to follow ? Tying it in-the-end, is conceptually simpler, and can be done almost blindly - on the other hand, tying the ABoK#1080 in the bight and then retucking the tail ( in order to achieve a wider, 3-rope-diameters nipping loop - if they do that retucking ) is quicker ! I am interested in learning what do knot users prefer, a simpler or a quicker method ?

Someone isn't looking/reading here. ::) No, not ABoK #1080, which is tied on the Bight, whereas what Lee shows is tied with the End. The term "In-the-end" is improper, which implies tying in-the-bight near the end of the rope, which may be what you are implying. As for re-tucking the tail, I've not seen it done.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 05, 2015, 10:24:03 PM
Someone is nt looking / reading here, indeed !  :)
tying the ABoK#1080 in the bight and then retucking the tail ( in order to achieve a wider, 3-rope-diameters nipping loop )
If you know how they tie it, tell it... The one way ( I had described ) or the other ( I had described, too ? )
WHO told you that if a knot can be tied in-the-bight, it can not be tied in-the-end, too ?  :)

Why are you falling in every next pitfall, I really dont know...
Sugar and oxygen !  :) :) :)

P.S. In-the-end, is Ashley s term, used in ABoK dozens of times - which does not mean what you mean...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 05, 2015, 10:34:15 PM
   Personally, I would tie it in-the-bight, and then retuck the Tail End through the nipping loop - and I would tie it faster than if I had tied it in-the-end, by retracing a common bowline - but this is perhaps due to my TIB-mania...  :) I really do not know what most knot users would choose.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 05, 2015, 10:35:18 PM
Here's a hint, if you'd care to read it. :)
They call it a re-traced or re-threaded bowline


p.s. Stop hovering over your keyboard. I can't pound as fast as you. :)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 05, 2015, 10:39:04 PM
   Yes, I have seen that - but sometimes the fig.8 knot is called retraced fig.8., without this meaning that it should be tied only that way, and not in-the-bight. Tie it in-the-bight all the way till the re-tucking of the Tail End, and measure the time you need. I believe you, too, will tie it faster than in-the-end.

P.S. I had a very good teacher, dL !  :)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 05, 2015, 10:53:45 PM
Climbers will tie their "tie in" eye knot using the working end, unless they connecting to a carabiner.
The Fig.8 tie in eye requires to first locate where to pre-tie a Fig.8, go through the harness loop (and leg loop), then do the retracing moves to complete the eye portion.

The Bowline is tied with the working end as well, not requiring a pre-tied knot before the eye.

So, unless one is using a connector to clip into, tying with a bight won't work. Unless one wants an unnecessarily bulky knot.

Anchor configurations vary and tying with a bight may be favorable at times.

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 05, 2015, 10:53:56 PM
Yes, I have seen that - but sometimes the fig.8 knot is called retraced fig.8.
It's a good term, as the Fig.8 is re-traced, not the eye. In the case of the Bowline the whole knot, including the eye, is re-traced. This is why I prefer to call it a twinned bowline.


Tie it in-the-bight all the way till the re-tucking of the Tail End
Because you're not a climber it's forgivable that you mightn't know, or remember, climbers like to tie into their harness "hard" (i.e. sans carabiner). This precludes using the in-the-end method. 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 05, 2015, 11:09:26 PM
   OK, dear climbers.
   However, I still believe that if you want to tie the knot as a free end-of-line loop, it would be faster, and perhaps less prone to mistakes, to tie it in-the-bight, and retuck the Tail End at the very end. Alan Lee would be able to tie it in less than 5 seconds !
   A comment on a previous post : Ashley uses the term "in-the-end" as opposite ( knotting antonym  :) ) of the term "in-the-bight". Perhaps it would be more correct, indeed, to use the term "with-an-end", but then this will rhyme with the term "with-a-bight", which is a different thing (1) - the main difference here is the topological difference between TIB and not-TIB knots, so we should better have two terms which will denote knots tiable as TIB and not-tiable as TIB, and this is what the pair of terms "in-the-bight" and "in-the-end" does.

1. http://igkt.net/sm/index.php?topic=5300.0
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 05, 2015, 11:19:41 PM
   Regarding the re-tucking of an ABoK#1080 end through the nipping loop, I am sure that climbers do not do it for the reason Alan Lee had thought about it ( which was to increase the width of the nipping loop, and the strength of the first curve ), because the strength of their knots is more than adequate for the sizes of their ropes and their loads. Perhaps they do it only because they prefer the resulting orientation of the free end, so it will not run the danger to be pushed back, and out of the nipping loop  ( ? ).
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 05, 2015, 11:24:57 PM
   OK, dear climbers.
   However, I still believe that if you want to tie the knot as a free end-of-line loop, it would be faster, and perhaps less prone to mistakes, to tie it in-the-bight, and retuck the Tail End at the very end. Alan Lee would be able to tie it in less than 5 seconds !
   
Well, that's an entirely different topic, isn't it.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 05, 2015, 11:25:38 PM
If there is a consensus to continue using the term "bight" then the two terms, with a bight or in a bight  (both distinctly different terms) works for me.
"With an end" or "using the working end" (equal) works as well.
Being consistent for the sake of effective/efficient communication is the goal.

I am not a fan of using too many acronyms: TIB, TWB, WAE, UWE, etc. Looks like alphabet soup.
 It is easy enough for all of us to "keystroke" a few more letters.  :) :) :D :D  ;D

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 05, 2015, 11:32:30 PM
   Regarding the re-tucking of an ABoK#1080 end through the nipping loop, I am sure that climbers do not do it for the reason Alan Lee had thought about it ( which was to increase the width of the nipping loop, and the strength of the first curve ), because the strength of their knots is more than adequate for the sizes of their ropes and their loads. Perhaps they do it only because they prefer the resulting orientation of the free end, so it will not run the danger to be pushed back, and out of the nipping loop  ( ? ).
Climbers do it for one reason only... to increase the security of the Standard Bowline.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 05, 2015, 11:37:50 PM
If there is a consensus to continue using the term "bight".

  It would require an educated and brave :) decision to abandon Ashley s terms, and use some others...
  Although Ashley explicitly refers to the nautical meaning of the term, and denotes as a "bight" a wide, "open" arc, less than the half of a circle - while we use it even when the "bight" is more narrow, i.e., when we are talking about something Ashley calls "a loop". However, even Ashley could not tie a knot "with a bight", without squeezing this bight and turn it into a loop !
 
Looks like alphabet soup.

 :) :) :)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 05, 2015, 11:39:57 PM
Climbers do it for one reason only... to increase the security of the Standard Bowline.

ABoK#1080 is already MUCH more secure than the Standard bowline ! I was asking why they use the re-tucking of ABoK#1080 s end.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 05, 2015, 11:43:47 PM
Climbers do it for one reason only... to increase the security of the Standard Bowline.

ABoK#1080 is already MUCH more secure than the Standard bowline ! I was asking why they use the re-tucking of ABoK#1080 s end.
As for re-tucking the tail, I've not seen it done.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 05, 2015, 11:48:42 PM
   Oh, I thought that you had not seen the re-tucking in Alan Lee s knot, not on the knot used by the climbers !
   Then, if they trust this knot, I imagine that they may also trust the "shrunk" bowline on-the-bight, and use it instead of the fig.8 knot .
   http://igkt.net/sm/index.php?topic=4687.0
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 05, 2015, 11:48:58 PM
If there is a consensus to continue using the term "bight".

  It would require an educated and brave :) decision to abandon Ashley s terms, and use some others...
  Although Ashley explicitly refers to the nautical meaning of the term, and denotes as a "bight" a wide, "open" arc, less than the half of a circle - while we use it even when the "bight" is more narrow, i.e., when we are talking about something Ashley calls "a loop". However, even Ashley could not tie a knot "with a bight", without squeezing this bight and turn it into a loop !
 
Looks like alphabet soup.

 :) :) :)

Xarax' use of the term in-the-bight was correct and proper. Initially, I thought that he was meaning something else.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 06, 2015, 12:04:02 AM
   Oh, I thought that you had not seen the re-tucking in Alan Lee s knot, not on the knot used by the climbers !
I did miss it, initially.

 
  Then, if they trust this knot, I imagine that they may also trust the "shrunk" bowline on-the-bight, and use it instead of the fig.8 knot .
   http://igkt.net/sm/index.php?topic=4687.0
I've looked at this knot previously. I'd be interested in seeing how this knot would perform as a secure Bowline tie-in knot.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Luca on June 06, 2015, 02:20:08 AM
 Hi all,

From what I saw, in the manuals of the CAI (Club Alpino Italiano, ie Italian Alpine Club) the re-traced/re-threaded Bowline is considered as an old knot,to which today is preferable the use of the Fig. 8 loop(EDIT: see reply #165).Actually this knot is still used by a fair number of climbers,at least in Germany(or Austria..) and Italy(I remember that is preferred especially when one is in certain positions on the rope,but do not ask me which because I do not know/remember...).German/Austrian climbers call it "doppelter Bulin knoten"."Bulin"  should be a frenchism from "Boline",which in turn should be a french anglicism from "Bowline".Italian climbers,who learned this knot probably by the Austrian climbers, call it "nodo Bulino reinfilato"(re-threaded Bowline knot).
In the italian forums that time ago I had occasion to visit,is strongly recommended (contrary to the Fig.8 loop)the use of a double Overhand as a back-up knot around the standing part.
Some germanic and italian videos(the first two seem to show the same knot:left-handed Bowline as base and the second "nipping turn" over the first;on the third  maybe is the same but with a more casual setting;on the fourth the base is a right-handed Bowline(the second "nipping turn" is always over the first:wanted or simply "easier and instinctive"?)):

https://www.youtube.com/watch?v=SzZvD3EkJnA

https://www.youtube.com/watch?v=KUHA_DuJXng

https://www.youtube.com/watch?v=EOziEgsvQLk

https://www.youtube.com/watch?v=O5I4Xh8jCqE

                                                                                                                               Bye!
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 06, 2015, 02:59:03 AM
Thank You Luca.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Mobius on June 06, 2015, 05:19:19 AM
Mobius 'Eskimo' Bowline (PET, TIB, EEL)

This might be new, though I note it has a passing resemblance to Lee's Eskimo 8 bowline's.

I discovered this several weeks ago and was taken by how much it looks like the Mobius Loop. I have called it what I have for now, only because it reminded me so much of the Mobius Loop. I really haven't trialled it much at all, only a few strength and untying trials under standard loadings. It performed well from what little I have done so far.

The tying method is easy enough as an end of line loop (I'm sure you can figure it out for yourself :) ), though the TIB method is a bit more 'magical' and can wait for now.

The symmetry of the knot structure lends itself to being a verifiable knot. I am also fairly comfortable saying it is secure, even with the limited trials I have done to date. It does all the 'acronym soup' stuff as well.

Cheers,

mobius

(Here is a link to the Mobius Loop: https://docs.google.com/presentation/d/1CA0xdlWfeUt4FrGCXeyzEUDOIui8pkWYBWqF2iJ0ytE/edit?usp=sharing)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 06, 2015, 10:47:06 AM
   There are thousands of "Eskimo" "Janus" bowlines ( like the one shown in the previous post ) - and it should be expected that some of them will be TIB (1). However, this particular one is not acceptable, because, during the tying and dressing stages at least, and regarding the Standing Part after the eye, the tip of the first bight can slide in between the adjacent segment of the on-going eyeleg and the tip of the last bight, pass from the other side of it, and then the knot degenerates into something else ( into a more complex ABoK#1051, with an additional collar on the on-going eyeleg ).
   Moreover, with such complex knots, where the Working End makes so many U-turns, there is no reason why we will not have wider, rounder nipping loops ( encircling three rope diameters ) - as the nipping loops of most eyeknots tied by Alan Lee.   

1. http://igkt.net/sm/index.php?topic=4703.msg30384#msg30384
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Mobius on June 06, 2015, 02:38:45 PM
   There are thousands of "Eskimo" "Janus" bowlines ( like the one shown in the previous post ) - and it should be expected that some of them will be TIB (1). However, this particular one is not acceptable, because, during the tying and dressing stages at least, and regarding the Standing Part after the eye, the tip of the first bight can slide in between the adjacent segment of the on-going eyeleg and the tip of the last bight, pass from the other side of it, and then the knot degenerates into something else ( into a more complex ABoK#1051, with an additional collar on the on-going eyeleg ).
   Moreover, with such complex knots, where the Working End makes so many U-turns, there is no reason why we will not have wider, rounder nipping loops ( encircling three rope diameters ) - as the nipping loops of most eyeknots tied by Alan Lee.   

1. http://igkt.net/sm/index.php?topic=4703.msg30384#msg30384

In other words, dress the knot properly, or it might degenerate into something else. One wonders how many others knots would become "not acceptable" if we didn't dress them right? Maybe a Plait Loop might turn into a Farmer's Loop if we didn't dress it right and therefore become "not acceptable"? Maybe I should have used the words "not acceptable" when I actually did trial the Pretzel Loop and it collapsed by folding in half? That knot needed to be dressed a lot differently to avoid capsize, to the extent it really was a different knot.

And of those "thousands of "Eskimo" "Janus" bowlines", how many are: PET, TIB, EEL, easy to tie, easy to untie, non-jamming and have been trialled (at least a little)? I will not accept the "not acceptable" tag based solely on apparently flimsy thinking.

Unlike some who just theorize about knots, I actually go to the trouble of trialling a knot I put forward (admittedly, not a great amount in this case). This knot (if dressed properly) does not turn into something else easily from my experience. Instead, it does dress nicely and it does load nicely in the trials I have conducted.

I am quite willing to hear from someone who actually does some other trials with this bowline and finds that the knot does not meet expectations. However, a theoretical "not acceptable" from someone who admits they are not interested in doing trials means nothing to me in this case.

Cheers,

mobius



Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Mobius on June 06, 2015, 03:02:16 PM
  I will not accept the "not acceptable" tag based solely on apparently flimsy thinking.
  Unlike some who just theorize about knots,

  Do not accept it ! Keep tying it ! Keep trying the knots the way you do !  :)

Thanks for that comment, I will keep doing what I feel is the best way to learn about knots  :)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 06, 2015, 04:02:56 PM
   I should had not made any comments regarding the flimsy, indeed, knot shown in Reply#159, but I just wished to notice how easily this knot degenerates into some other knot ( and which other knot ) - and how the Working End of bowline-like loops can be wandering around its nub, without doing what it should do : 1 :  "feed" the nipping loop, so it will become wider and rounder, by passing through it at least 3 times. 2 : stabilize the nipping loop, so it will not run the danger to "open up" and degenerate into an open helix. 3 : become attached to the knot tied on the Standing Part, in a stable and secure way. Those tasks should be accomplished with the minimum possible amount of material, with as few turns and twists as possible - otherwise a significant portion of the tensile forces induced into the nub will be "wasted" aimlessly = consumed in generating friction ( and wear/heat ) in areas where it is not required. For a good practical knot, nec quam plus minimum.   
   It is a common symptom of inexperienced knot tyers, to tie unstable, or overcomplicated, amorphous ( and so ugly ) knots. They tend to believe that they should not "theorize" about knots, but they should jump into "practice" as soon as possible  :) - and that, by entangling ropes into some "new", to them, knots just a couple of times ( sometimes before they had even learned how to tie them properly - which, for me, requires to tie a knot at least a dozen times...), on the first material and load happens to fall into their hand, they accomplish something great. I do not underestimate the joy of turning a flexible straight line into a whatever rigid globular knot - but I also do not underestimate the power of abstraction, the value of frugality regarding the required amount of material, and the virtue of deprecation of most of the knotted tangles. Knot-tying is not much more difficult than simple arithmetic, but, just as arithmetic, it does have rules - and some twists of its own.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 06, 2015, 10:58:32 PM
   There are thousands of "Eskimo" "Janus" bowlines ( like the one shown in the previous post )
1. http://igkt.net/sm/index.php?topic=4703.msg30384#msg30384

   8.192, to be precise !  :)
   And I am taking into account only those "Eskimo" bowlines where the nipping turn AND the collar turn encircle 3 rope diameters !
   If we relax this condition, and we allow narrow turns and collars ( so, sharper curves ), the number jumps out of the window.
   What we really need in not any TIB one of them, but one that can also be tied in-the-bight easily, following an easy to memorize and to remember method. Also, one on which the segments follow some pattern - because such knots can be easily inspected after they are dressed : a mistaken tying or dressing would turn the "ordered", "regular" arrangement of the segments into an amorphous conglomeration, and so it could be spotted at once. 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Luca on June 08, 2015, 02:48:33 AM
Hi all,

From what I saw, in the manuals of the CAI (Club Alpino Italiano, ie Italian Alpine Club) the re-traced/re-threaded Bowline is considered as an old knot,to which today is preferable the use of the Fig. 8 loop.

Evidently the memory made me a joke, because trying to retrieve online excerpts from the CAI manuals regarding the re-traced/re-threaded Bowline,I found nothing in the descriptions of this knot that mentions the fact that is no longer used or no longer recommended to use it.All this in fact concerns the description of the SIMPLE Bowline(nodo Bulino semplice) ::).(But in the CAI schools is widely taught the fig. 8 loop indeed).

                                                                                                                        Bye!

P.S. alpineer,thank you for the new videos about the methods for the Butterfly loop! ( http://igkt.net/sm/index.php?topic=5210.msg34070#msg34070 )


Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 08, 2015, 05:28:21 AM
Thanks Luca. You can view more ABK methods by clicking my youtube username or this link...  https://www.youtube.com/channel/UCnFcaU1Qbkw_fZA8_yxkspw
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alanleeknots on June 09, 2015, 07:17:40 AM
   Personally, I like two more variations of the Lee s Eskimo 8 bowline, shown at the attached pictures.
   Beautiful knots !

Hi All,
         Xarax, Thanks for help, here are the result of my load test.
                    First, breaking test with 1/4 rope, I fond is easy to untie from the second collar.
       
                    second heavy load test with 8mm blue water rope, see third photo right side picture, It is easy to rotate the second collar loose, once it loose, 2 diameter of rope can fill in the hole of the collar. Now we come back and see the left side picture the Eskimo nipping loop already on the bottom of it stock(no sure I use the right words) from now on even more weight you add on it, the tail side eye leg will not able to move anymore to tighten the eight knot inside, even you break the rope, I assume the second collar will remain easy to untie.
                   I hate writing, properly it take you ten minute to write all these, with my poor English it take me more then two hours to write poor me, you are welcome to correct my English. You can make me a better man tomorrow. I hope you understand these broken English.
                   謝謝 alan lee
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 09, 2015, 07:19:48 AM
the re-traced/re-threaded Bowline is considered as an old knot,
to which today is preferable the use of the Fig. 8 loop.
But then they hardly know all the knots of the knotting
universe that have been revealed by X. et alia in these
threads, and elsewhere.

There is a more sensible way to "re-thread' a bowline
--since you will NOT be needing "EEL", don't make the
knot so, with a pointless finish, just because you think you
have to follow the same darn diagram that has become so
stale in decades of echoing!  Rather, the re-threading can
be done in a much better way, getting much nicer-looking
curves (to what end this matters is of debate), and still TIB
and more secure.
And novel, which counts for something maybe, maybe not.   :P

And a better, much better, "fig.8 bunny ears", as well as
--contrary to D.Merchant's assertion-- a quite decent "fig.9
bunny ears"
as well, of like construction.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alanleeknots on June 09, 2015, 07:31:33 AM
Hi All,
         Just said hi to Dan up strait.

         More test here With Lee s Eskimo 8 bowline(A). it jam at 2000lbs.

         謝謝 alan lee
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 09, 2015, 08:36:54 AM
Hi Alan,

This is really good - but may I please enquire about the following questions:
1. Is the threshold of jamming at 2000 lbs force? Or is it somewhere between 1500 and 2000 lbs? Are you able to pinpoint the tension force which triggers jamming?

2. What was the rate of applied tension force to your knots? That is, how fast did you increase the load?

Quote
first test with 1/2 inch solid braid nylon rope, I have a small comer lock pull as hard as I can, I don't have scale
       no idea what is the exact weight, but I can show you the picture while the knot still on tension.
       so far I have been tested  quiet a bit of knots ( if I have to guess I have to said at least 1200 lbs,)
       after the loading, it is very easy to untie, and hold quiet a solid form.

       Second test with 8mm blue water rope, do the same thing pull it as hard as I can, the result are the same. It look good to me.

       Third test with 1/4 nylon solid braid nylon rope, with my multiple force device loaded it with 650 lbs.
       With the small size rope it does create little problem to untie it, how hard to untie it, let put it this way,
       I am 5 feet 5 inches tall, weight 138 lbs., active and have a strong hand,  I use my finger nail to push it back and fore with
       my best effort and get it untie in 45 second.

       This loop have to untie it from the top collar(second collar).

Could you please confirm the type of rope you used in your test? I am a little unsure!

Note: Not trying to be difficult - I am just seeking to compile accurate data :)

Thanks,

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 09, 2015, 02:44:37 PM
@Alan Lee
So, which one of the three Lee s Eskimo 8 bowlines do you prefer ? Which is more easy to untie after really heavy loading ?
The one shown at :
http://igkt.net/sm/index.php?topic=4480.msg35904#msg35904
Or any one othe two shown at :
http://igkt.net/sm/index.php?topic=4480.msg35910#msg35910

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: McKnottee on June 09, 2015, 03:08:52 PM
https://www.youtube.com/channel/UCnFcaU1Qbkw_fZA8_yxkspw

Thanks for the vids.  :)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 09, 2015, 11:52:55 PM
You're welcome McKnottee.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alanleeknots on June 10, 2015, 07:59:12 AM
@Alan Lee
So, which one of the three Lee s Eskimo 8 bowlines do you prefer ? Which is more easy to untie after really heavy loading ?
The one shown at :
http://igkt.net/sm/index.php?topic=4480.msg35904#msg35904
Or any one othe two shown at :
http://igkt.net/sm/index.php?topic=4480.msg35910#msg35910

Hi All, 
        Xarax, I like the one with three rope diameter nipping loop , it is the most secure one, amongst all the knots I have,
                   the Eskimo nipping loop was lock in by the figure 8 knot, the tail was embrace by the nipping loop and the tail
                   side eye leg. the nipping loop lock the figure 8 knot and the figure 8 knot lock on it own.
                   Just so many combination locking effect. 
                  This four here are more easy to untie, Lee s Link bowline,  LeeZep bowline (Inspaired by Xarax),Lee s φ crossing
                    knot bowline, Lee s Eskimo 8 bowline).

                謝謝  alan lee
                   
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 10, 2015, 12:55:50 PM
   Thank you, Alan.
   Perhaps you should test it on Dyneema ?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Mobius on June 13, 2015, 03:34:04 PM
Climbers will tie their "tie in" eye knot using the working end, unless they connecting to a carabiner.
The Fig.8 tie in eye requires to first locate where to pre-tie a Fig.8, go through the harness loop (and leg loop), then do the retracing moves to complete the eye portion.

The Bowline is tied with the working end as well, not requiring a pre-tied knot before the eye.

So, unless one is using a connector to clip into, tying with a bight won't work. Unless one wants an unnecessarily bulky knot.

Anchor configurations vary and tying with a bight may be favorable at times.

SS

I remember using the name 'Retraced Figure 8' earlier on and being told that the name 'Figure 8 Loop' was the only name needed for #1047. As I was new to this knot at the time, this had the consequence that I thought climbers were not 'retracing it' and were therefore regularly tying this knot in the bight and using it as a clip-in. That is not so, apparently.

An unfortunate effect of this simple misconception was that I went to a lot of trouble to find a bowline that would tie very easily in the bight, as easy as a Figure 8 Loop. It now seems that if a bowline is tiable in the bight (TIB) then this is an almost irrelevant consideration when the bowline's application is as a tie-in for a climber's harness (no carabiner). A climber wants a simple way to tie a knot in an 'endless rail' method. A 'TIB' method will hardly matter I think.

Cheers,

mobius
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 13, 2015, 04:18:43 PM
Climbers will tie their "tie in" eye knot using the working end, unless they connecting to a carabiner.
The Fig.8 tie in eye requires to first locate where to pre-tie a Fig.8, go through the harness loop (and leg loop), then do the retracing moves to complete the eye portion.

The Bowline is tied with the working end as well, not requiring a pre-tied knot before the eye.

So, unless one is using a connector to clip into, tying with a bight won't work. Unless one wants an unnecessarily bulky knot.

Anchor configurations vary and tying with a bight may be favorable at times.

SS

I remember using the name 'Retraced Figure 8' earlier on and being told that the name 'Figure 8 Loop' was the only name needed for #1047. As I was new to this knot at the time, this had the consequence that I thought climbers were not 'retracing it' and were therefore regularly tying this knot in the bight and using it as a clip-in. That is not so, apparently.

An unfortunate effect of this simple misconception was that I went to a lot of trouble to find a bowline that would tie very easily in the bight, as easy as a Figure 8 Loop. It now seems that if a bowline is tiable in the bight (TIB) then this is an almost irrelevant consideration when the bowline's application is as a tie-in for a climber's harness (no carabiner). A climber wants a simple way to tie a knot in an 'endless rail' method. A 'TIB' method will hardly matter I think.

Cheers,

mobius

Hi mobius.

Your conclusion, in part, is correct in regards to a climber's tie in loop. Not all climbers tie in this way, harnesses being different, etc. And then there can be the use of a tied with a bight loop for anchoring purposes, equipment hauling, etc.
Outdoors enthusiasts, workmen, rescue techs and others can have a use for other -than- working end tying methods.

And then there is the pure pursuit of knot tying exploration that some find alluring.

I am sorry that the "unfortunate effect" you've encountered may have bothered you, but I am very glad that you've been "bothered".   :) ;)

Thank you for your contributions!

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: roo on June 13, 2015, 04:20:33 PM
A climber wants a simple way to tie a knot in an 'endless rail' method.
Having to thread the end of the rope though or around an object comes up often, beyond climbing applications, too.  Since a lot of on-the-bight loops don't have a good, simple end-tying method, it's natural to look to other types of knots.  The removal of this on-the-bight constraint allows for freedom to find knots with better security, jam resistance, simplicity, and other high-importance, non-acronymized ( ;D) practical properties.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 13, 2015, 05:16:02 PM
Since a lot of on-the-bight loops don't have a good, simple end-tying method, it's natural to look to other types of knots.

   A lot ? ?  :) :) I do not know ANY-one... and nobody does ! What really happens is that, some times, the in-the-bight tying method of some TIB knots is better = simpler, easier to learn and remember, and quicker, than the in-the-end tying method - but that does not mean that " they don't have a good, simple end-tying method " ! When this happens, it can only be another reason to PREFER this knot, not to dismiss it, and search for a knot that is not TIB ! This is an amusing "reasoning" : Because there is not a simpler and quicker method to tie a certain knot in-the-end than to tie it in-the-bight, " it is natural to look to other types of knots ", that can not be tied in-the-bight at all !  :) :) ( So the method to tie them in-the-end is, by definition, simpler and quicker than the method to tie them in-the-bight - simply because the later does not even exist !  :) :)

The removal of this on-the-bight constraint allows for freedom to find knots with better security, jam resistance, simplicity, and other high-importance, non-acronymized ( ;D) practical properties.

  The TIB condition is NOT a "constrain", it is a bonus regarding versatility. And the bright "idea" implied on this sentence, that TIB-ness is not a "practical property"  :) :), or it is not of any "high importance" ( perhaps because it is "acronymized" !  :) :) ), is pure nonsense ( if, of course, it is not promoted for some "practical" reason - to show how jam-resistant and simple/easy-to-tie is the so-called "Zeppelin loop", for example  :) :) :))
   Nothing regarding security, jam resistance, simplicity or any other property of lower or higher importance should be sacrificed, of course, in order to choose a TIB from a non-TIB knot ! !  However, people who have not understood the easy methods we have to tie TIB knots, and so find it difficult to figure out such knots, or to tie knots that can be tied following such a method, try to diminish the importance of TIB-ness : the well known story of sour grapes, again... The simple fact is that, ceteris paribus, a TIB knot is, by definition, preferable to a non-TIB one, because, simply, TIB-ness can not be a negative value !  :) It can not cancel what a knot already has, so, if/when it has all what a not-TIB knot has, to  also be TIB is a bonus, and an ADDED, positive value regarding versatility, which should not be underestimated.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 14, 2015, 07:10:29 PM
Since a lot of on-the-bight loops don't have a good, simple end-tying method, it's natural to look to other types of knots.

   A lot ? ?  :) :) I do not know ANY-one... and nobody does !
What really happens is that, some times, the in-the-bight tying method
of some TIB knots is better = simpler, easier to learn and remember, and quicker,
than the in-the-end tying method - but that does not mean that
" they don't have a good, simple end-tying method " !
If you fix your notion of what "simple" is at
a reasonable point, there are some knots that
aren't so simply tied by the end but which come
easily via a TIB method.  I know of such an eye knot
where the tail makes a quite simple half-hitch, 270deg.
passage; but it does this in a rather convoluted S.Part
tangle, which itself doesn't come easily PET so to
be held and impaled by the tail.  So, this eyeknot while
appealing in result and coming fairly easily TIB is not
so happily tied with the tail --where one would be forced
to essentially tied some form around fingers holding it
just so in preparation for the tail's contribution to making
it complete, stable.

Quote
The TIB condition is NOT a "constrain", it is a bonus regarding versatility. And the bright "idea" implied on this sentence, that TIB-ness is not a "practical property ...
When you use it as your litmus test to accepting the knot,
it obviously is a contraint.  And what is practical is defined
by the particular practice --which if TIB is irrelevant means
just that, nevermind that somewhere in some other knotting
need there might be benefit to that aspect.
And, of course, the same reasoning will support using a TIB
knot no matter whether it is EEL --a point that you and I
defended with the example of wanting to put in an eyeknot
for quick, temporary use in a long rope, and having no need
for loading both ends; so, some TIB bowline comes in nicely,
even it it would make an ugly thing with both ends loaded;
we do not need or want to use the butterfly here, no.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 15, 2015, 01:42:47 AM
there are some knots that aren't so simply tied by the end but which come easily via a TIB method. 

To whom am I talking ? To roo ?
Of course there are - I had said it many times, and I had even pointed out that they may even be tied more quickly, in-the-bight - and even more safely, in the sense that it would be more difficult / rare to tie those knots wrongly, if we follow a TIB method.
BUT THIS HAPPENS TO KNOTS WHICH ARE ALREADY TIB. We can also compare their tying in-the-end method, with tying in-the-end methods OF OTHER TIB KNOTS !
So, the "idea" that we should abandon a TIB knot, that is not as easily tied in-the-end as another TIB knot, or that is not as easily tied in-the-end as in-the-bight, and select a NON-TIB knot instead, is the purest, highest form of nonsense I had ever read ! I could nt had imagined such a thing, even in a thousand years...

When you use it as your litmus test to accepting the knot, it obviously is a constraint. 

 Please, read, slowly, the phrase :
 ceteris paribus, a TIB knot is, by definition, preferable to a non-TIB one.
 Read it again ( repetition is the mother of learning ):
 ceteris paribus, a TIB knot is, by definition, preferable to a non-TIB one.
  Now, read it in RGB ( that is "colourful"  :) )
  ceteris paribus, a TIB knot is, by definition, preferable to a non-TIB one.
  ceteris paribus, a TIB knot is, by definition, preferable to a non-TIB one.
  ceteris paribus, a TIB knot is, by definition, preferable to a non-TIB one.

ceteris paribus, a TIB knot is, by definition, preferable to a non-TIB one

   If you had not understood it by now, go to a nice summer place, NOW !  :) ( Yesterday, if possible... because your two today s posts, are - how to say it politely ?- entangled ( Erwin Schroedinger s term )
   https://en.wikipedia.org/wiki/Quantum_entanglement
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 15, 2015, 03:37:59 PM
   Let me try to say the same things, with other words :
   We are not talking about choosing a TIB knot which is difficult to be tied in-the-eye, instead of an also TIB knot, which will offer the same things, and will be easy to be tied in-the-eye, of course !
   Also, we do not talk about a TIB knot which is difficult to be tied in-the-bight, period. Such a knot will seldom be tied by a knot user as TIB, so why it should be TIB in the first place ? When I am not able to figure out an easy to learn, remember and implement TIB tying method for a TIB knot, I dismiss it immediately - although I keep in mind that, actually, there may be such a method, but I have not learned/discovered it yet...
   We are talking about NOT choosing a TIB knot, because it is difficult to be tied-in-the eye, AND choosing a not-TIB knot instead, which is easy to be tied-in-the eye - and this "talking" is a desperate attack on TIB knots, often orchestrated by people who do not know such knots, or do not know how to tie them in-the bight \: a typical sour grapes approach, by knot tyers who can not learn anything new, and they try to convince themselves that there is nothing new under the sun, or there is nothing worth learning. Combined with the accidental fact that "I" happen to like to learn and tie TIB knots ( and who "me" is the same person who tie only "random", or "decorative", or "overcomplicated" knots, who "steals and nicks other people s images and he posts them", who is "a charlatan and also a nuisance - a  PITA, who largely does not contribute in a constructive way", who, although is not (yet ? ) "waterboarding" people, nevertheless he is "keyboarding" them, etc, etc. ), made some notknot-tyers here to try to declare that TIB-ness is just an "acronymized" property, without any "practical" importance. The truth is that I am glad they have now reached the end of their line, and they are forced to attack properties of knots, because they can not attack me... Their only next step, is to start defending GLUE, and dismiss knots altogether, just because I happen to tie knots...  :)
   Of course, when/if, in a particular application, TIB ness is not needed, or when-/if it can not be used ( because we have, for some reason, to tuck the free end of a the line through a ring, for example ), TIB-ness will be no factor in our decision ! However, we do not have only knots for particular applications :)  :). If that was so, we would had thousands, millions of different knots, because we have thousands, millions of different applications. We want knots that can be used in as many applications as possible, because we want to remember, and to be able to tie, dress and inspect quickly and correctly, as few knots as possible. Even if TIB-ness will not be required in a particular application, we will still tie a TIB knot we know and trust, because it will be required in another application !  As I had pointed out whimsically, TIB-ness may be of zero value, but it can not be of negative value ! :)
   There are few, only, knots which are difficult to be tied in-the-end. And I am not talking about overcomplicated, big knots - we dismiss those knots because they are overcomplicated and big, not because they can not be tied easily ! Most of the simple practical knots we know and use, can be easily tied in-the-end - although few, only, of them can be tied-in-the-bight , and even fewer can be tied-in-the-bight easily enough... However, as we come to appreciate the versatility ( and the beauty, I would add ) of TIB knots, as we learn more about knots, in general, so we can "design" them to meet our demands AND be TIB as well at the same time, and as we learn more about the topological "tricks" regarding TIB-ness ( as the "haltering the collar" tying method ), we find new TIB knot we had not known till now  ( or, even if we knew, we had not appreciated ).
   I had seen that there are TIB hitches which are BETTER, and tighter, than almost all the not-TIB hitches,  and that there are TIB fixed and adjustable loops and binders which offer at least anything any not-TIB loop and binder offers. Of course, there are many people who prefer to die, than to acknowledge the value of ANY of those knots - and the recent attack on TIB-ness in nothing else than a desperate effort to blur the issue, and to throe mud in some beautiful, superb TIB knots they had not been able to tie, and they can not understand or accept why. 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 15, 2015, 07:22:59 PM
   Let me try to say the same things, with other words :
"Literature" [sic] !  (sorry, I'm skipping most, now --time)

Quote
We are not talking about choosing a TIB knot [that] is difficult to be tied in-the-eye,
instead of an also TIB knot, [that] will offer the same things,
and will be easy to be tied in-the-eye, of course !
But I keep reading that you reject out of hand
non-TIB knots, and yet some might well work.

Quote
Please, read, slowly, the phrase :
 ceteris paribus, a TIB knot is, by definition, preferable to a non-TIB one.
Whose definition?  --yours!
In fact, if one simply wants a knot in some point
of a line --and some mariners do this for marking--,
a TIB knot is by definition not all so good, as there
is some chance of it being untied.

Quote
Also, we do not talk about a TIB knot which is difficult to be tied in-the-bight, period.
Such a knot will seldom be tied by a knot user as TIB, so why it should be TIB in the first place ?
Because of some desirable properties of this knot
for use when finished; difficult tying might be just
an accepted price for performance.  --a possibility.

I will suggest that the majority of those rope users who
tie a Yosemite bowline are unaware that it is TIB --at least
I've never seen that aspect explicitly indicated.  And yet
the knot is much used, much known (to that extent,
but obviously not completely); it does its job.  And if one
were to find a version in which some change of crossings
lost the original's TIB aspect, it would make no difference
to those users; conceivably, the version would improve some
actually needed aspect.

Only if you broaden your range of needs to be open-ended
and somehow imply a limitation on known knots would there
be value to the YoBowl's TIB aspect --which would provide for
some in-broader-use-domain use of the YoBowl.

I will leave the TIB aspect in some standing as "strength"
--often nice to one's thinking, but often without effect in practice.
And "better", often only in some small degree.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 15, 2015, 07:45:15 PM
Please, read, slowly, the phrase :
 ceteris paribus, a TIB knot is, by definition, preferable to a non-TIB one.
Whose definition?  --yours!

   Dan Lehman, your situation does not improve !  :) :) :)
   By the definition of what does ceteris paribus mean !  :) :) :)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 17, 2015, 01:46:43 AM
Some more Eye Knots to examine...

These eye knots are (I think) another creation of knotting master Alan Lee... maybe Luca can weigh-in with some history/facts please?

These eye knots contain a single helix nipping structure - however, the first collar-capstan manoeuver doesn't orient in the same way as the original #1010 Bowline. In a standard/normative Bowline, the 2 legs of the collar structure are parallel and both enter the nipping structure from the same direction. In the 'Myrtle', the legs of the collar enter the nipping structure from opposite directions.
It in effect forms a secondary single helix structure - 'offset' around the initial helix nipping structure's crossing point. Then, it continues to form the 'collar-capstan around the SPart to finish.
Of note, is that it places 3 rope diameters inside the helical nipping structure.

I think Dan Lehman originated the term 'Myrtle' to describe Bowline-like structures with this type of manoeuver (Luca... check please)? And it seems that a significant sample of Alan Lee's creations use this 'myrtle-like' manoeuver as the basis of the structure?

I have referred to these structures as 'Eye Knots' although they do contain a key element (or 'essence') of the standard #1010 Bowline - which is the single helix nipping structure. What differs, is the subsequent manoeuvers to eventually form the collar-capstan.

I need some opinion on this 'myrtle' manoeuver as it doesn't create the standard collar-capstan we see in the standard #1010 Bowline.

Specifically, is this type of structure deserving of the title 'Bowline' ?

Or is it simply an Eye Knot containing a single helix nipping structure - and therefore closely related to the standard Bowline -  but missing the collar-capstan structure?

EDITED: Edited for clarity...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 17, 2015, 02:01:14 AM
Related to my post above are detailed images showing what appears to be termed a 'Myrtle Bowline' - I am not saying that I agree with this term...(without universal consensus). Morel likely than not, the geometry is a helix within a nipping helix - and offset around its crossing point.

The Alan Lee 'Bowline' variants are shown because they are built from the 'Myrtle:Helix-to-helix' nipping structure.

I need some opinion/comment on this please...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 17, 2015, 02:26:10 AM
Zoranz, can you please provide comment on the geometry of these Sheet Bends please.

I need a rationale for how best to present knots so that key structures can be observed by readers/viewers/learners.

I have stumbled around looking for descriptive terminology - but have not found any universal agreement/consensus. Maybe you could weigh-in from a 'descriptive geometry' point-of-view?

Terms have been tried - eg 'front view' - 'detail view' 'aspect A' - Versus - 'regular view' 'classical view' 'normal view' 'aspect B' etc etc

The attached photos have been named 'front' or 'rear' - but this is only for file-naming purposes on my computer - so I can keep all my knot photos in some sort of logical order (instead of a chaotic filing system)... So don't let my image names confuse the subject matter of this topic!
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 17, 2015, 02:43:31 AM
More image rotations...

Images uploaded to create discussion.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 17, 2015, 02:51:20 AM
More standard (normative) #1010 Bowline images.

Zoranz - would welcome your expert opinion on these - ie how best to depict the images and more importantly - why (ie sound reasoning for doing so).

Thanks :)

EDIT: Note, please ignore my file naming...this is simply so I can save my images in a logical order on my computer.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 17, 2015, 05:38:32 AM
Related to my post above are detailed images showing what appears to be termed a 'Myrtle Bowline'
...
I need some opinion/comment on this please...
I like the *anti-bowline* version, which is the reverse
of this myrtle knot.  And I like it with a 2nd turn of
the tail through the nipping loop, to give a rounder set
of diameters (a trio) for the S.Part to curve around,
and to give move securing friction against the S.Part's
turn loosening.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 17, 2015, 06:15:54 AM
I like the *anti-bowline* version, which is the reverse
of this myrtle knot.  And I like it with a 2nd turn of
the tail through the nipping loop, to give a rounder set
of diameters (a trio) for the S.Part to curve around,
and to give move securing friction against the S.Part's
turn loosening.

  I like this post - which is well written, in plain English, with correct, syntactically, sentences even I can understand. Moreover, the poster succeeds in describing verbally yet simply a knot, and expresses his opinion on this knot openly and sincerely, using this verb we should not be afraid to use more often : "I like". At the end of the day, given that all sufficiently convoluted/complex knot will "do the job", which knot we will prefer at each particular instance depends on our knowledge ( how big is the set of the knots we know ), our experience ( how many of the members of this set we can tie easil , quickly and correctly ), and, last but not least, which knots we like.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 17, 2015, 07:00:05 AM
is this type of structure deserving of the title 'Bowline' ?

   Of course it does !
   There are two elements which are distinctive here :
   First, the "link".
   As "llnk" I have described any turn tied on the returning eye leg, before of after the "proper" collar, around the rim of the nipping loop. This "link" may encircle the crossing knot of this loop, or may not.(1)(2)
   Second, the collar : It may be a "proper" bowline collar, where the continuation of the eyeleg enters into the nipping loop from the "proper" side, the same side it enters into the common bowline s nipping loop, then makes half a turn around the Standing End, and then enters into this nipping loop again, from the same side it had existed from previously ( and the same side it exits from the nipping loop of the common bowline ). Or, it may be a "Myrtle" collar, which, after it makes this turn around the Standing End, enters again into the nipping loop from the opposite side.
   ( This distinction, between a "proper" and a "Myrtle" collar can be made in the case of the "Eskimo" bowlines, too - where the continuation of the returning eye leg enters into the nipping loop from the opposite side it does in the Standard bowline, and then makes a turn around  ( "collars") the on-going eyeleg, not the Standing End.

   I have said it many times, and I will say it again, because it is such a simple thing, but it also a very useful and related to the fundamental elements of the bowline, the "nipping structure" ( the knot which corresponds to the nipping loop of the common bowline, and is tied on the Standing Part before the eye ), and the "collar structure" ( the knot which corresponds to the collar of the common bowline, and is tied in the Standing Part after the eye ).
   We should see the geometries of those two structures separately, i.e., we should see how each of those structures would appear, if its pair was not visible : In other word, we should see the bowline as if the "nipping structure" or the "collar structure" was invisible or made from a completely transparent material.
   Some of the bowlines you show have yet another characteristic, which can be considered separately : The last part of the Standing Part before it exits the nub of the knot and becomes the Tail End ( we can call this segment "Tail Part" ), is re-tucked through the collar : a very useful addition, which enlarges the curve of the collar, and it may also turn a bowline-like loop into a TIB knot (3).

1. http://igkt.net/sm/index.php?topic=4314.15
2. http://igkt.net/sm/index.php?topic=4314.msg26928#msg26928
3. http://igkt.net/sm/index.php?topic=4695.0
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 17, 2015, 07:37:18 AM
I have always had difficulty with your use of this term:

Quote
"proper" collar

And I have been thinking about this for quite some time and cant come up with anything marvelous other than perhaps 'symmetric collar'.
By 'symmetric', I mean a collar that has parallel legs - with both legs entering the helical nipping structure from the same direction.

If the legs of the collar entered the helical nipping structure from opposite directions, it would not be 'symmetric'. Note that this is my blundering about trying to find something more descriptive than the word 'proper'.

Also, do you or Dan have a good quality photo of what you refer to as 'anti-bowline' structure?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 17, 2015, 08:14:44 AM
I have been thinking about this for quite some time

   Evidently, you only think that you have been thinking about it !  :) :) Because you just don t read my lips : Do I speak about "parallel" or not-parallel legs of the collar ? No - and I have a reason for NOT doing this ! I am speaking about the topology of the "proper" versus the "Myrtle" collar, NOT the geometry ! There may be "proper" collars with parallel or with not-parallel=crossing legs ! And the legs of the Myrtle" collar are always crossing each other !
   I am only speaking about the sides ( the SIDES ) of the nipping loop the continuation of the returning leg enters into and exits from. A nipping loop has two sides : a line that penetrates it enters into it from one side, and exits from it from one side, ok ? Having this in mind, read again what I have been writing six years now !
   My KnotGod ! DO FOLLOW the returning eye leg along its path ! See what its end is doing, as it "moves" within the already formed nipping structure, and as it, in its turn, forms the collar structure. DO NOT see this structure only as it is when it is finished ! DO NOT speak about the geometry of the legs of the one or the two collars !
   ( There may be more than one collar in the "collar structure", so there may be more than one pair of "legs of the collar" )
   
P.S.1. On the contrary, the "proper" collar is a-symmetric, and the "Myrtle" collar is symmetric ( in relation to the nipping loop ).
P.S.2. This is perhaps the ONLY case dL does NOT need to provide a picture !  :)  :) "Anti-bowlines" are the bowline-like eyeknots where the continuation of the returning eyeleg enters into the nipping loop from the side it enters in the "Eskimo" bowline. The (four) "Eskimo" bowlines are the simplest "anti-bowlines". Again, I am talking about the "side" of the nipping loop, NOT about the legs of the collar ! 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 17, 2015, 03:35:28 PM
Xarax, evidently you think that what I am thinking is in fact what you think I am thinking when in reality I like to think about things by think-tank thoughts :)

I am aware that Dan had favored the 'Anti-Bowline' moniker... However, what I remain unclear on is the underpinning reasoning behind choosing the term 'anti'.

I also acknowledge your reasoning on the collar structure and how it manoeuvers around the SPart or an eye leg. What is needed is some clear content that is presentable in a document that can be easily understood by the general (lay) public (and with accompanying high quality photos to illustrate the concepts).
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 17, 2015, 04:37:02 PM
what I remain unclear on is the underpinning reasoning behind choosing the term "anti'.

   The bowline has two parts : the first, is the knot tied on the Standing Part before the eye, the "nipping structure" - which, in the case of the two common Standard bowlines ( the left- and the right-handed ), but also in the case of the four "Eskimo" bowlines, is a single nipping loop.
    Now, when you have formed this part, and you had also formed the eye of the loop, it is time to drive the continuation of the returning eyeleg through the nipping loop. HOW ? By which side are you going to enter into this nipping loop ? This is the moment of truth, regarding what you are going to tie : a bowline, or an anti-bowline. And it is the ONLY moment that is going to determine which of the two you are going to tie. So, it is reasonable that, when you enter from the one side, you call what you tie "the X knot", and when you enter by the opposite side, you call what you tie "the anti-X knot".
   After the returning eye-leg has passed through the nipping loop, it has  to collar something ! What will collar, which "limb" of the nipping loop it can collar, is already determined by the SIDE from which it had entered into, and the side from which it had exited from, the nipping loop. If you had made the X decision, you have to tie a bowline, and to collar the Standing End. If you had made the anti-X decision, you have to tie an anti-bowline, and collar the on-going eyeleg. Therefore, the decision you made in the first place, during the moment of truth, the side by which the returning eyeleg enters into the nipping loop, is critical, and the two possible choices determine the two broad classes of bowline-like loops : the bowlines, and the anti-bowlines.   
   Well, that is what I think dan Lehman thinks !  :) :)

   My point was to concentrate to the side of the nipping loop into which the "moving" end of the Standing Part, while it is tracing its path though the nipping loop, enters into or exits from. We have to define those two sides somehow. Again, SIDES of the nipping loop, not legs of the collar !

   I do NOT agree with the neither the pictures nor the labelling of the anti-bowline you show ! The forms you show them, they are NOT stable knots ! When the on-going eyeleg has been loaded, the Tail End will settle in a position at its one or its other side, and this is of HUGE importance ( topological, geometrical, and structural ) ! How the last segment of the Standing Part ( the segment I call the "Tail part" ) is squeezed by the on-going eyeleg, plays a MAJOR role regarding security and, possibly, strength. Show the "Eskimo" bowlines as they are when they are LOADED, and with eyelegs more or less parallel. Then, you will see that there are FOUR "Eskimo" bowlines - if you wish to use the terms right- and left-handed for them, two of them will be left-handed and two right-handed. Then, you have to distinguish those pairs with yet another term - I am not sure that it is correct to label them as "Kalmyk" and "anti-Kalmyk" ... I am not sure which of the four was the original "Kalmyk bowline" ( IFF it was one, only, of them, i.e., if this term was so exclusive, as to it define completely one, only, knot...)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 17, 2015, 04:53:10 PM
the collar structure and how it manoeuvers around the SPart or an eye leg.

  First, the "collar structure" does NOT manoeuvre around anything - simply because it does not move !  :) It is the knot tied on / with the Standing Part after the eye.
  Second, what you call SPart, is a WRONG term, because anything before the Tail End is Standing Part !  :)
  The correct term is "Standing End" ( the segment outside the knot, beyond the collar - to distinguish it from the "Standing Part", the segment inside the knot ) - or any other term you choose, but NOT Standing Part - because an eye leg is inside the knot, so it is part of the Standing Part !

------------------------------------------------------------------------------------------------------
   We have also to distinguish the two eyelegs some how - and by using one, only, adjective !  :) 
   For the time being, I use the terms "on-going" eyeleg, and "returning" eyeleg, because I believe that we should better define a direction on all segments of the Standing Part, and this direction should better lead to the Tail End - so the "first" eyeleg is "on-going" ( to the tip of the eye ) and the "second" eyeleg is "returning" ( from the tip of the eye ). I guess that can also choose many other pairs of adjectives, to distinguish / denote the difference between the two eyelegs.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 17, 2015, 05:36:57 PM
Also, do you or Dan have a good quality photo of what you refer to as 'anti-bowline' structure?
?!  --as opposed to the one you have already posted,
to which I noted that swapping tail/S.Part converted
it from *bowline* to *"anti-bowline"* ?!

If you want just the base structural parts, you can
show the start-via-tail-leg-return-insertion through
the turNip for the bowline/Eskimo bowline pair
--although in that case, given their respective contin-
uations, those working ends would/should be headed
in different directions; whereas the one above is more
nearly the same, putting in a loop around a loop.
(One could also, re the anti-bowline case, suggest
that there is often more challenge to defend against
--or to tolerate in the loaded knot-- the turNip opening
to a more obvious helix than staying qua "loop"/circle.)

As X. recognized & I confirmed some time ago, my term
"anti-bowline" is derived from "anti-cyclone", which pertains
to orientation/direction of like things --opposite only
in this quality but not in basic nature, or somehow one
the undoing of the other.
And, as I've also noted, it is an overloading of "bowline",
as by a 2nd sense (an other "loading" of the word),
"bowline" is the title for both (pro-)/anti- --i.e.,. that they
share in common the bowlinesque nipping loop and so
on, just differing on direction of tail re-entry.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 17, 2015, 06:00:01 PM
Hi agent_smith.

Just some input for the discussion.

So many variations/orientations to consider!

In the cropped and attached picture (yours) I find that, in my mind at least, if the eye knot contains this basic structure, with the tail outside or as shown, then I consider it in the bowline family. The collar part can make multiple or otherwise convolutions around the standing part. Afterward, the tail can do all manner of things. But, as long as the knot has the basic #1010 element, it is a bowline, IMO.
The exception,  perhaps, being the Eskimo family. Maybe included because it is an accepted name(?) only.

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 17, 2015, 06:18:55 PM
I am aware that Dan had favored the 'Anti-Bowline' moniker...
However, what I remain unclear on is the underpinning reasoning behind
choosing the term 'anti'.
About which you should be clear, now; HOWEVER,
you would be wise to consider how well the term suits
general presentation --it would take a direct presentation,
at least.  In other words, I'm clear on it and X. is and ... ,
but that doesn't mean that it is without potential trouble
if put to the general populace.  And, I noted already the
"overloading" of it, as both "anti-" and "bowl," are in
my thinking halves of anOTHER "bowl." word.  I acknowledge
this overloading --which, mind, comes also with "loop" and
why I use "eye knot", a novel term w/o confusion from
anOTHER meaning, but just confounding a bit maybe from
its rank newness in the literature (finding companionship
in "eye splice", I hope).

So, I wrote to clarify for you; I respect that such understanding
nevertheless might not compel one to use such terminology
overall.  (SOMEtimes, the structural aspects are a blur, too:
i.e., the "opening into helix" aspect, which seems more likely
for anti-bwls, can also happen in the good ol' #1010 (and into
capsizing to a "pile-hitch noose" or helical eye knot);
and some anti-bwls can be pretty good on preserving the
roundness of the turNip.
.:.  One might sit back an reflect on how helpful the
distinction is on one's own particular set of knots  presented!?
(In other forums --here, w/knotters--, we need handles to focus
our meaning on something, and fashion terms on the fly for such
with-the-initiated chatter.  What goes out to other forums might
need editing/revising/adjusting/refining.)

Quote
I also acknowledge your reasoning on the collar structure
and how it manoeuvers around the SPart or an eye leg.
What is needed is some clear content that is presentable in a document
that can be easily understood by the general (lay) public (and with
accompanying high quality photos to illustrate the concepts).
Pardon in that I've skipped this, in time deficit.
I could see "bight" as maybe a helpful descriptor?
One can "loop" or "bight" with a tail, in binding/securing/
stabilizing the turNip --myrtile loops, and #1010
bights, and EBDB does both (and EBSB goes off the deep
end, Yo.-Yo.-ing!   ;D  )

Quote
Second, what you call SPart, is a WRONG term,
because anything before the Tail End is Standing Part !
NO, I protest!!  In fact, as I allowed earlier re the dubious
*acronym* aspect to "S.Part/SPart", one might see this
Dan-term as making a departure from the commonly given
definition (and implications) of "standing part"
--which commonly connotes a inactive part of the knot
during the tying process (but maybe ignoring this on
some *backwards*-tied knots (where shortness enables tying
end-outwards, so to speak --e.g., snood to long-line of a trawl)).

What I've wanted was a term for the
bears full force into the nub, until U-turn (or ...)".
.:.  So, in that sense, one can see X. wrong about their
equality --right about the old term, wrong about the new.
IMO--, and I think most will agree, the complete knot is
in need  of denotation of parts --and maybe more often
& importantly, than is the inchoate knot.
(ANd maybe "standing part" better suits its old sense,
and "S.Part" should find another term.  I've used the
shorthand, though, as so often it is the former --or. to
X's critique, the leading part of that-- that ultimately
becomes what I see as the latter.  (I have read in Ashley
"the lead" but don't fully grasp what he means by that,
and think it too isn't quite what I am seeking.)


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 17, 2015, 06:26:58 PM
So many variations/orientations to consider!
Or not : i.e., your point should resonate strongly,
as the general reader will more likely be put off
by such number, than enthralled by all the options.
And a culling / choosing --hard though that is--
might be in order.  Or some sense of *principals*
and *subordinates*?!

There can be ways to generally point to the vast
set of possibilities, showing structural parts and how
things can be *modularized* and modules combined
in new ways --the YoBowl finish slapped onto the
"End-Bound" wrap slapped onto the "double" turn
of common dbl.bwl., and so on.

Likely some of the knots will be faster to tie,
and others which might sell by virtue of surer
security (or more sure easy untying, where use
is of well-monitored and short-lived knot : e.g.,
on a tow line for impromptu momentary use)
might take more careful working.  #1010 can
be put in with haste; more complex knots usually
not so much, but if tying in for some period of
use, the tying time is a minor concern.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: zoranz on June 17, 2015, 06:55:08 PM
ZoranZ, can you please provide comment on the geometry of these Sheet Bends please.
When i tie Bowline, i do it always on the same way. My principle is: it is better to know one way well, then to use various ways and don't be sure if you did tie the knot without mistake. Xarax would said: you can not learn old dog new tricks. And I do not feel any benefit / need for different variants. Because of this I prefer this presentation (let's call: "basic"). If it were me to decide, I would certainly call this basic view as "front". But my arguments have no weight and depth like Dan's, Xarax'x, Luca's, roo's etc. Therefore, this is only one unimportant opinion of "amateur".
On the other hand, if I talk about the Sheet Bend - in my head I have only one image (considered as standard), which for me is the basic view. And I should like to call it "front". But that "front view" is in complete contrast to front view of the bowline. Because of these contradictions I give up further explanation.
For me, the "front" means: The basic view that I have when I start to tie the knot.
Well, according to my vision, I always like to watch bowline in "vertical" position. And the bend in "horizontal".
Further, it is my opinion that the Sheet Bend needs only one diagram.
Because of detailed illustrations - it is well to display both views. I would both images linked in a way to get a second look by simply rotating the bend in the area of ​​180 degrees.
Sorry, English is not my native language and therefore it is not very clear what "the poet wanted to say." But anyway I'm honored that Mark asked me for assistance and I consider it is my obligation at least to try something. Maybe anything will be usefull :)
Regards, ZZ
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 17, 2015, 08:13:53 PM
it is my opinion that the Sheet Bend needs only one diagram.

  I agree. And I would be ready to denote THIS side as the "front" side of the "corresponding" bowline. IFF the bowlines was corresponding to the Sheet bend - but it does NOT ! There is no relation, other than superficial, skin-deep, and Ashley-parroting oriented, between the bowline and the Sheet bend, but I will not repeat my reasoning here, because there are just some things just some people can not just learn / understand.

P.S. See the attached picture, for the "front" view of the genuine Sheet-bend bowline.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 17, 2015, 08:40:31 PM
the complete knot is in need  of denotation of parts --and maybe more often importantly, than is the inchoate knot.

   I was talking about the complete knot.
   In the case of an eyeknot, but also in the case of the one link of a bend, we have three parts ;
1. The Standing End. This is the part of the line OUTSIDE the nub, from the one side. Also, this is the only part of the knot which is loaded by 100% of the load.
2. The !@#$%^&*()_+
3. The Tail End. This is the part of the line OUTSIDE the nub, from the other side. Also, this is the only part of the knot which is loaded by 0% of the load.

   Now, one can denote the 2 nd part as he wishes - for the time being, I call it "Standing Part", but we can well find another term, and keep the term "Standing Part" to denote a part of the knot during its tying stage ( a part of the inchoate knot ), the other part being the "Working Part".

P.S. For yet another pair of terms, read :
   http://igkt.net/sm/index.php?topic=4757.0
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 18, 2015, 12:47:24 AM
Hi Dan,

Quote
my term
"anti-bowline" is derived from "anti-cyclone", which pertains
to orientation/direction of like things --opposite only
in this quality but not in basic nature, or somehow one
the undoing of the other.

This is the kind of reply I am looking for - some sound reasoning to give authority to a descriptive term.

So this is your basis for preferring the term 'anti'?

Is there wide-spread consensus for the use of the term 'Anti Bowline' to describe the so-called 'Eskimo/Kalmyk  Bowline' structure? (I have trouble with the term eskimo).

That is, are you in preference for use of the term 'Anti' to describe any Bowline that has a collar-capstan structure that performs a manoeuver around an 'eye leg' instead of the SPart?

Could you also label each of the parts in the Bowline #1010 image?

Can you confirm the Bowline Vs Anti-Bowline definition image?

Can you describe the Alan Lee Eye Knot - how it fits within your definition?

Many questions.... :)

EDIT: With Luca's help - I have added what I think is one of the worst examples of photography and topological layout I have ever seen. And Dan Lehman's replies are all but Greek to me. In tying both knots depicted - it seems to contradict the definition of 'Anti' Bowline - but like I said... its all Greek to me :)
Here is a response to a question:

Quote
    Dan, which one is the Myrtle, and which one is the Anti-Bowline?


The left one, if properly oriented/dressed, is an anti-bowline (my term);
you show it in odd (dis)array, instead of with the *bowline*-characterizing
(and here "bowline" in inclusive of "anti-") nipping loop of the S.Part.  The
right one is easier to see, it being in better form.

ORRRRrrr, just referring to your righthand image, loading the right end
makes an anti-bowline, loading the left end a bowline (Myrtle).
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Luca on June 18, 2015, 01:16:40 AM
Hi Mark,

(If still it is worth!)Here are some references about the "Myrtle" and Anti Bowline knots:

http://asiteaboutnothing.net/cr_constrictor.html#myrtle

http://asiteaboutnothing.net/cr_constrictor.html#psychedelic-bowlines

http://igkt.net/sm/index.php?topic=357.msg2731#msg2731

http://igkt.net/sm/index.php?topic=1481.msg10359#msg10359

http://igkt.net/sm/index.php?topic=5079.msg33473#msg33473

                                                                                                                                  Bye!
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Luca on June 18, 2015, 01:58:32 AM
In his book "Symmetric Bends",Roger E. Miles remarks that ABoK #1445(called by him "a Lesser Carrick bend"),despite appearances,is,in itself,a symmetric knot,but that has no hope of being symmetrically loaded,unless it is loaded by all the four ends.
It reports also that Harry Asher called this bend "Boobash"(ie Ashley's boob)in that the bend would not be so worst as described by Ashley.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 18, 2015, 04:40:19 AM
It reports also that Harry Asher called this bend "Boobash"(ie Ashley's boob)
in that the bend would not be so worst as described by Ashley.
And I took the contrary position : "ash" can be expanded
to "Asher" sooner in ascending lexicographical order than
to "Asley", and IMO Asher's championing this end-2-end
knot was wrong.  I had it tested in 1/4-inch 3-strand nylon
rope, and the tester reported that it kept rolling, so he gave
up trying to break it.
.:.  AsheR is the boob!


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 18, 2015, 04:59:14 AM
Is there wide-spread consensus for the use of the term 'Anti Bowline
 to describe the so-called 'Eskimo/Kalmyk  Bowline' structure?
Goodness, no.  That term is uttered in the IGKT forum,
but I don't know if it occurs elsewhere, and it's hardly
a term that is self-explanatory.

The biggest issue I have with it --and I'm happy to use
it here, in lieu of a better-conceived term-- is that I also
want "bowline" to stand for the entire set, to make sense
in "Is this a *bowline*?" --which should include, IMO,
the so-called "anti-bowlines".  I think that the awkwardness
of my terminology is impediment enough for  the journey
into common parlance.

Maybe we can find a replacement, with TWO terms, to divide
the *bowline* set per this re-entry (which, itself, on some
standing-back overview of what we might amass as members,
seem inadequate to the task of good nominal sub-setting),
based on the fact that the return of a #1010 bowline
makes an overhand (just after tuck through the turNip)
and going the other way does NOT knot (more quickly lending
the construction to TIB knots).

At this stage, we might ask Is there a good reason to use some
term of differentiation on just this (small?) aspect?
  (I might
have just fancied noting the distinction, lacking circumspection
to judge its importance in the grand scheme of things.  E.g.,
one can form a very-much-like-the-#1010-bowline TIB,
and the Eskimo bowline well resists opening the central nipping
loop into a helix.

Note that instead of poking the tail through a formed turNip
one can press and turn the S.Part against the tail and form
the nipping loop around the tail.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 18, 2015, 09:19:17 AM
Hi agent_smith.

Just some input for the discussion.

So many variations/orientations to consider!

In the cropped and attached picture (yours) I find that, in my mind at least, if the eye knot contains this basic structure, with the tail outside or as shown, then I consider it in the bowline family. The collar part can make multiple or otherwise convolutions around the standing part. Afterward, the tail can do all manner of things. But, as long as the knot has the basic #1010 element, it is a bowline, IMO.
The exception,  perhaps, being the Eskimo family. Maybe included because it is an accepted name(?) only.

SS

What the image shows is a compound structure consisting of two elemental forms - namely, one loop, one bight - which together make up the nucleus of the #1010 Bowline. Only when the elements are combined and interact as a knotted structure in a working knot do they become nipping coil and collar.

So, to my logic, a true bowline must contain in it's core a specific entanglement of loops and bights - at least one of each. Therefor, if any "so called" bowline contains, in it's core, less than or other elements in place of (eg. the Munter form), it is not a true bowline, but a pseudo or a meta bowline.
Scott, your Braided "Bowline" deletes the #1010's bight collar and replaces it with a loop derived collar structure, and as such your knot is based solely on loops. Thus, my logic precludes it from having true Bowline status. Ditto for "mrytled" knots.       
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 18, 2015, 10:45:26 AM
This is the kind of reply I am looking for - some sound reasoning to give authority to a descriptive term.

   This is the kind of reply that is completely redundant - because we have already discussed about this same subject in many posts in the Forum, for years now ! You better learn hoe to use the "Search" option !
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 18, 2015, 11:13:36 AM
Is there wide-spread consensus for the use of the term 'Anti Bowline' to describe the so-called 'Eskimo/Kalmyk  Bowline' structure? (I have trouble with the term eskimo).

It would be a bold / brave step to substitude the "Eskimo" term ( which you are right you have trouble with...) with the term " anti-bowline". Personally, I would nt disagree - provided the term describes what I think dan-Lehman thinks, and what, probably, is NOT what you think !  :) :)

are you in preference for use of the term 'Anti' to describe any Bowline that has a collar-capstan structure that performs a manoeuver around an 'eye leg' instead of the SPart?

NO !
Personally, I am in preference for use the term "Anti" to describe any bowline that has a returning eyeleg that enters into the nipping loop from the side it enters in the "Eskimo" bowlines ( that is, the opposite side it enters into the "Standard" bowlines ). "Anti" means opposite of !
DO NOT speak about what the collar does ! The collar is the secondary structure of the bowline - it is the nipping loop which is the primary structure. How the returning eyeleg enters into this nipping loop, is of primordial importance regarding the two broad classes of bowlines. ( The "Standard" and the "Eskimo" bowlines ).

Can you confirm the Bowline Vs Anti-Bowline definition image?

NO ! Because it is completely WRONG !
ALL the four "Eskimo" bowlines are Anti-bowlines ( and then some...). And both right-handed and left-handed bowlines are bowlines. You show two, only of each class - which can lead the reader to mistaken assumption about the rest.

...which one is the Myrtle, and which one is the Anti-Bowline ?.


   THAT is the kind of question that PROVES whoever has asked it, has not understood, yet, anything about the matter !
   The "Myrtle" is a kind of collar, where the one leg of it exits from the nipping loop, and the other leg of it enters into the nipping loop, from OPPOSITE SIDES. The other kind of collar is the "proper" collar of the common bowline, where the one leg enters into, and the other leg exits from, the SAME SIDE.
    So, the "Myrtle" is a term that tells something about the COLLAR !
   The "anti-bowline" is a kind of bowline-like eyeknots, where the returning eyeleg enters into the nipping loop from a certain side of it, which is the side from which it enters in the cases of the "Eskimo" bowlines, and the opposite side from which it enters into the "Standard" bowlines.
    So, the "anti-bowlines" belong to a class of bowlines, determined by the SIDE of their NIPPING LOOP  their returning eyeleg enters into their nipping loop. It is a term that tells something about the NIPPING LOOP !

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 18, 2015, 11:35:57 AM
Can you describe the Alan Lee Eye Knot - how it fits within your definition?

It is debatable if this eyeknot should be described as a "bowline" at all - because it lacks either a "proper" or a "Myrtle" colar.
If we decide that it is, it is :
First, a "Link" bowline : the returning eyeleg makes a 360 degrees turn ( an O-turn ) around the rim of the nipping loop.
Second, this turn is also a turn around the crossing point of the nipping loop.
Third, the second leg of the collar around the Standing End, instead of entering into the nipping loop, it enters into the loop of the "link". So, in this sense, this eyeknot has no collar.
My suggestion was to drive this leg through the opening formed by both, the nipping loop AND the "link", in an effort to make both wider and rounder, and the grip of the Tail End even more secure.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 18, 2015, 11:56:29 AM
Hi agent_smith.

Just some input for the discussion.

So many variations/orientations to consider!

In the cropped and attached picture (yours) I find that, in my mind at least, if the eye knot contains this basic structure, with the tail outside or as shown, then I consider it in the bowline family. The collar part can make multiple or otherwise convolutions around the standing part. Afterward, the tail can do all manner of things. But, as long as the knot has the basic #1010 element, it is a bowline, IMO.
The exception,  perhaps, being the Eskimo family. Maybe included because it is an accepted name(?) only.

SS

What the image shows is a compound structure consisting of two elemental forms - namely, one loop, one bight - which together make up the nucleus of the #1010 Bowline. It is only when the two elements are combined and become a knotted structure that they carry the potential to transform the loop element into a nipping coil and the bight element into a collar.

So, to my logic, a true bowline must contain in it's core a specific entanglement of only loops and bights - at least one of each. Therefor, any "so called" bowline which contains, in it's core, less than, or other elements such as the Munter form is not a true bowline, but a pseudo or a meta bowline.
Scott, your Braided "Bowline" deletes the #1010's bight collar and replaces it with a loop derived collar structure, and as such your knot is based solely on loops. Thus, my logic precludes it from having true Bowline status. Ditto for "mrytled" knots.       

Hi alpineer.

I think we may be on the edge of a discussion that has a long history here. "What defines a Bowline?" went on and on with opinion and argument. And here we are again....

I don't agree that the "composite loop" I offered back when is not  bowline. It has a U shaped collar around the standing part, albeit after some travel. It has the constricting coil where it belongs and it has the loop part (can't forget this part!) whose leg parts enter and exit as the "parent loop does. So, to me it is very much bowline like.
I guess I could have called it anything, Braided1010, Aussie eyeknot, Ultimate Non-Zeppelin loop or whatever. I wasn't claiming a name, just offering, discussing a concocted eyeknot.

So, with friendly discussion in mind, would a bowline-like affair, where the collar completely encircles the standing part before driven through a doubled constriction not be a bowline?

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 18, 2015, 12:06:34 PM
Could you also label each of the parts in the Bowline #1010 image?

First row : Standing End.
Second row : Collar ( in this case, a "proper" collar, not a "Myrtle" one. We can further label the two legs of this collar, as "first" and "second" - following the order of the Working End in its path within the knot.
Third row : Nipping loop. We can further distinguish the two "legs" of the nipping loop which are crossed at the crossing point of the nipping loop, and the crossing point itself.
Fourth road. On-going eyeleg, Tail End, returning eye-leg. We can further label the tip of the eye.

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 18, 2015, 12:15:43 PM
Roger E. Miles remarks that ABoK #1445(called by him "a Lesser Carrick bend

   I had tested this knot in a dozen, at least, different materials, from 5.5mm to 12.5mm. If dressed and pre-tightened properly, is a very secure bend, at least for up to moderate loadings ( 25% of the MBS ). Ashley s comments are misleading - and this bend is certainly NOT the worse of the four possible. I would nt recommend it as a stand-alone bend, of course - but as an element of a compound knot, be it a bend or a loop, it is very tight and secure, and it can be used, together with other elements, to tie many more complex secure knots.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 18, 2015, 02:47:43 PM
Quote
I think we may be on the edge of a discussion that has a long history here. "What defines a Bowline?" went on and on with opinion and argument. And here we are again....

We are indeed! And I think the reasons for this are:
1. Lack of clear photos to precisely illustrate each point - words alone are complex and can be difficult to interpret in the exact manner intended by the author - a photo speaks a thousand words
2. Lack of consensus - mainly individuals arguing there own cases - and often developing into personal attacks (which then makes me tune out...)
3. The information is spread wide and far in this forum - multiple searches often yield conflicting opinion - and it all become overwhelming

So.... here I am trying to bring this all together in one cohesive body of work - and this is no small task.

I am determined to use high quality photos to precisely illustrate each concept - and at the same time - try to gather as wide an arc of agreement as as reasonably achievable. Note that some have flatly refused to assist - and i guess that's their prerogative to do so... I want to try to avoid (as much as possible) lengthy and difficult to interpret wordiness!!

Mark Gommers
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 18, 2015, 06:05:59 PM
Could you also label each of the parts in the Bowline #1010 image?

First row : Standing End.
Second row : Collar ( in this case, a "proper" collar, not a "Myrtle" one. We can further label the two legs of this collar, as "first" and "second" - following the order of the Working End in its path within the knot.
Third row : Nipping loop. We can further distinguish the two "legs" of the nipping loop which are crossed at the crossing point of the nipping loop, and the crossing point itself.
Fourth road. On-going eyeleg, Tail End, returning eye-leg. We can further label the tip of the eye.

I find the concepts of pre and post interesting when applied to the legs of knot parts. We've been doing it for Eyes, so, why not the other parts? It has simplicity and consistency built in. Using this reasoning I find the terms pre-collar and post-collar to be preferrable when referring to it's legs. Same goes for the nipping loop.

Capstan? What's wrong with Stem, Mark?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 18, 2015, 08:36:39 PM
 Reply #210 to SS369 has been edited for brevity/clarity.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 18, 2015, 10:02:03 PM

  I find the terms pre-collar and post-collar to be preferrable when referring to it's legs. Same goes for the nipping loop.

  Then, we should denote as "collar" only its middle, curved part - what I use think as "rim" of the collar, which has an almost semi-circular shape. Its legs will be the almost straight segments, between this "rim" and the nipping loop. Also, the "pre-collar" and the "post-collar" legs of the collar sounds as a contradiction in terms : are the legs themselves parts of the collar, or not ? If they are, they can not be "post" something they belong ! If they are not, they can not be legs of it !
   Same with the nipping loop - where we have yet another ambiguity : Are those "legs" pre- or post- the crossing point of the nipping loop ? Are they "inside" or "outside" it ?
   Same with the eye legs : pre- or post- (of) what ? Of the eye ? Are nt they part of the eye ?
   We could possible add, in all those three cases, the word "tip", or the word "middle" : tip of the collar, tip of the nipping loop, tip ot the eye - or middle of the collar, middle of the nipping loop, middle of the eye. Then, I believe we can use the terns pre- and post-, indeed,
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 18, 2015, 10:39:29 PM
Scott, your Braided "Bowline" deletes the #1010's bight collar and replaces it with a loop derived collar structure, and as such your knot is based solely on loops. Thus, my logic precludes it from having true Bowline status. Ditto for "mrytled" knots.       

Hi alpineer.

I don't necessarily agree in regards to your thoughts on the the braided bowline. See the picture attached as to why I don't. I did not delete the bight that goes around the stem, standing part, single tensioned line, etc...., I just moved it up via a few crossings for them to engage the standing part along its length.

If have a correct understanding of your concept, then the only bowline that is true is one that can have something done with the tail afterward. (?)

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 18, 2015, 11:33:46 PM


So, with friendly discussion in mind, would a bowline-like affair, where the collar completely encircles the standing part before driven through a doubled constriction not be a bowline?

SS

It's all friendly, Scott.
According to my previously stated reasoning, no, not a bowline. Bowline-like or bowlinesque?... sure. But your mixing the terms bowline and bowline-like, whereas I differentiate them.
I want to limit the number of actual bowlines. Your "composite loop" is one example only of a knot that I would bar from the immediate family of Bowlines. The Farmer's Loop and the Karash Loops
are also excluded because of their more complex structural elements.  In the case of the Farmer's Loop, the Bowline's bight-collar is replaced by a loop-collar and the nipping loop is replaced by a Munter-shaped nipping element. As for the Karash, it also contains the Munter-shaped element.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 19, 2015, 12:19:30 AM
... a Munter-shaped nipping element.

   I use to call this shape as a "crossing knot" ( ABoK#206,#1171,#2079,#2089 ). However, the two legs of the Munter hitch are pointing to the same direction, while the two legs of a "crossing knot" point to opposite directions. Moreover, the Munter hitch is not meant to nip / grip the element around which it is tied, which is the case in most crossing-knot based eyeknots ( where either the "nipping structure", the knot tied on the Standing Part pre/before the eye, or the "collar structure", the knot tied on the Standing Part post/after the eye, are shaped like this ).
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 19, 2015, 12:33:57 AM


So, with friendly discussion in mind, would a bowline-like affair, where the collar completely encircles the standing part before driven through a doubled constriction not be a bowline?

SS

It's all friendly, Scott.
According to my previously stated reasoning, no, not a bowline. Bowline-like or bowlinesque?... sure. But your mixing the terms bowline and bowline-like, whereas I differentiate them.
I want to limit the number of actual bowlines. Your "composite loop" is one example only of a knot that I would bar from the immediate family of Bowlines. The Farmer's Loop and the Karash Loops
are also excluded because of their more complex structural elements.  In the case of the Farmer's Loop, the Bowline's bight-collar is replaced by a loop-collar and the nipping loop is replaced by a Munter-shaped nipping element. As for the Karash, it also contains the Munter-shaped element.

Yep, it's all good.

So, by your stated reasoning, would you bar your "Tresse Double Bowline"?
Just asking...

I do agree though, that too many eye knots contain "Bowline" in their name, but what's a guy to do? "Tresse Double Sort of, Kind of, Maybe Like A Bowline" Eye knot? "SSBraided Almost in the Realm of a Bowline" Eye Knot?  ;)

When I offered that tangle, I had started with a #1010 configuration and tried to add another structural element to attempt to enhance the grip of the standing part above the nipping section. Perhaps to mitigate or limit the strain at the suspected stress location where many have deemed the most prone for breakage, as I stated in that thread "Composite knot" http://igkt.net/sm/index.php?topic=4283.msg26651#msg26651 (http://igkt.net/sm/index.php?topic=4283.msg26651#msg26651)

It really is a conundrum, this name game.

SS

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 19, 2015, 12:40:36 AM
Scott, your Braided "Bowline" deletes the #1010's bight collar and replaces it with a loop derived collar structure, and as such your knot is based solely on loops. Thus, my logic precludes it from having true Bowline status. Ditto for "mrytled" knots.       

Hi alpineer.

I don't necessarily agree in regards to your thoughts on the the braided bowline. See the picture attached as to why I don't. I did not delete the bight that goes around the stem, standing part, single tensioned line, etc...., I just moved it up via a few crossings for them to engage the standing part along its length.

I understand your reasoning SS. I just don't agree with it, and for good reason I think. You're pushing beyond the normal limits of what defines the term bight and right into the realm of loop

If have a correct understanding of your concept, then the only bowline that is true is one that can have something done with the tail afterward. (?)

SS

I understand your reasoning SS. I just don't agree with it, and for good reason I think. You're pushing beyond the normal limits of what defines the term bight well into the realm of loop.

I don't necessarily have a problem associating yours and other knots, in some limited manner, with Bowlines. But I view them as different and more complex knotted structures beyond pure Bowlinism.

Per your question, I include in the Bowline family the Double Bowline, the Janus multi-bight-collar Bowlines, Dan's Y2K Locktight Loop, EBDB, EBSB, blah, blah, blah, etc.... and as you say, anything can be done with the tail part (afterwards).   
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on June 19, 2015, 01:07:30 AM
Scott, your Braided "Bowline" deletes the #1010's bight collar and replaces it with a loop derived collar structure, and as such your knot is based solely on loops. Thus, my logic precludes it from having true Bowline status. Ditto for "mrytled" knots.       

Hi alpineer.

I don't necessarily agree in regards to your thoughts on the the braided bowline. See the picture attached as to why I don't. I did not delete the bight that goes around the stem, standing part, single tensioned line, etc...., I just moved it up via a few crossings for them to engage the standing part along its length.

I understand your reasoning SS. I just don't agree with it, and for good reason I think. You're pushing beyond the normal limits of what defines the term bight and right into the realm of loop

If have a correct understanding of your concept, then the only bowline that is true is one that can have something done with the tail afterward. (?)

SS

I understand your reasoning SS. I just don't agree with it, and for good reason I think. You're pushing beyond the normal limits of what defines the term bight well into the realm of loop.

I don't necessarily have a problem associating yours and other knots, in some limited manner, with Bowlines. But I view them as different and more complex knotted structures beyond pure Bowlinism.

Per your question, I include in the Bowline family the Double Bowline, the Janus multi-bight-collar Bowlines, Dan's Y2K Locktight Loop, EBDB, EBSB, blah, blah, blah, etc.... and as you say, anything can be done with the tail part (afterwards).

Certainly OK to disagree.

I still believe that where the "Collar part" u-turns around the standing part, is U shaped (bight-ish) till it crosses and does other things.

I'm not trying to sell anything here, just explaining where I got to use the overused name.
Bowlinism is a great term. lol
Potentially subject to over usage.

Hopefully we haven't swung too far afield for agent_smiths desires.

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 19, 2015, 07:44:54 AM
Quote
Hopefully we haven't swung too far afield for agent_smiths desires.

No...but, I am starting to find it hard to piece everyone's posts/data into one comprehensible lump!

Part of the problem is the lack of high quality images - with arrows pointing to precisely the component that the poster is commenting (or arguing) about. I tend to get lost in a sea of wandering words..

My eyes are starting to bleed  :-[  and for example, I couldn't even locate the details about Bowline on the Bight (#1080) transformed.

So I turn to my good friend Luca once again...as he will sniff out all the historical details for me  :D

I like this transformed #1080 structure - very nice - and its very stable and secure.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 19, 2015, 09:15:55 AM
I like this transformed #1080 structure - very nice - and its very stable and secure.

   I, too, had thought of this loop some time ago, but I had dismissed it :
   http://igkt.net/sm/index.php?topic=4687.0
   Why ? Because, as it happens with all those knots where the Working End retraces the same path along a large part of the nub, they should be careful dressed ( so, they are not self-dressing, and they require some attention from the knot tyer ), and they can easily or accidentally be re-dressed in a non-optimum way... In particular, the Standing Part s first curve can be transformed from a wide, 3-rope-diameters one, to a narrow, 2-diameters one. In general, each individual line of a two-parallel-lines pair can easily "jump" "over" or "under" the other, can follow an inside or an outside track at each curve, etc, so the geometry of the knot can be transformed - and, in practical knots, it is the geometry which matters most.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 20, 2015, 07:32:16 AM
So, by your stated reasoning, would you bar your "Tresse Double Bowline"?
Just asking...

No. The pure essence of Bowlinism is present in the TDB. Repetition of #1010 parts is not grounds for barring. Witness the Double Bowline. The same reasoning applies to the TDB. Laying sequence and handedness do not factor into the matter.


I do agree though, that too many eye knots contain "Bowline" in their name, but what's a guy to do?

That's the crux of the conundrum...if we don't call them Bowline, what then do we call them? I.E. how do we name them? Well, like we would otherwise name any knot. By...
geometry
distinguishing feature
author/rediscoverer
association with established knotted forms/structures...
application... 
performance characteristic...
place discovered...
time stamp...   
other...     
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Mobius on June 20, 2015, 12:36:24 PM
...
The CorEssence limits what may be considered as true Bowlines. For example, the Karash Loop might be described as a "Munter" Bowline. However, it's . The same reasoning can be applied to exclude Scott's Braided Bowline from the family of true Bowlines as it does not contain a proper Collar element. On the other hand, all multi-collar and all multi-nipping turn Bowlines are true Bowlines.
 

Hi alpineer,

I am really unsure why the comment "Munter element excludes it from being a true Bowline" applies. When the B&B Bowline has it's final tuck removed we have the image I give you below. To me what I see in that image is a "Munter" style Bowline: It clearly has a dual turNip (the Munter) that secures a bight shaped collar. I do not see why this is not just another dual nip bowline like the Double Bowline or the Water Bowline, for example.

The "Munter" name has come up a few times in this thread as not being deemed as a suitable core for defining a bowline, to me it is. If the image I show you is not a bowline then the so called "B&B Bowline" certainly is not. Can you explain more please about the Munter core, with particular reference to my image?

Cheers,

mobius

B&B: https://docs.google.com/presentation/d/1u_yuaYi0fOTUL_90g4yzKPbHvS29Kf0QRfnOJrbRb3s/edit?usp=sharing
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 21, 2015, 01:39:23 AM
...
The CorEssence limits what may be considered as true Bowlines. For example, the Karash Loop might be described as a "Munter" Bowline. However, it's . The same reasoning can be applied to exclude Scott's Braided Bowline from the family of true Bowlines as it does not contain a proper Collar element. On the other hand, all multi-collar and all multi-nipping turn Bowlines are true Bowlines.
 

Hi alpineer,

I am really unsure why the comment "Munter element excludes it from being a true Bowline" applies. When the B&B Bowline has it's final tuck removed we have the image I give you below. To me what I see in that image is a "Munter" style Bowline: It clearly has a dual turNip (the Munter) that secures a bight shaped collar. I do not see why this is not just another dual nip bowline like the Double Bowline or the Water Bowline, for example.

The "Munter" name has come up a few times in this thread as not being deemed as a suitable core for defining a bowline, to me it is. If the image I show you is not a bowline then the so called "B&B Bowline" certainly is not. Can you explain more please about the Munter core, with particular reference to my image?

Cheers,

mobius

B&B: https://docs.google.com/presentation/d/1u_yuaYi0fOTUL_90g4yzKPbHvS29Kf0QRfnOJrbRb3s/edit?usp=sharing


Hi mobius,
The nipping structure of your knot is composed of a munter element plus a cross-stacked loop. The munter is a geometrically distinctive elemental form on it's own and deserves to be treated as such. It diverges from what defines the pure elemental structure of the bowline. My criteria for determining whether, or not, a knot is a bowline is based purely on the geometry and inter-tanglement of elemental forms. Why do I use this criteria? Simply because I want to limit the number of knots that would be categorized as bowlines. Understand that excluding a knot from being a bowline places no judgement - good, bad, or otherwise - on it's quality as a knot.

Now, if others want to use less defining criteria to determine bowline-ship, good luck. But be warned, the list of bowlines could grow exponentially. If you include your B&B knot on the list of bowlines then you must also include the Karash loop. Do you require all bowlines to have a bight component? If not, then you must include the Farmer's Loop, the Carrick loops, i.e. any eye knot which has a munter element in it's nipping structure. And it gets worse, once you've let the geometric "cat out of the bag" by allowing the munter. Where do you want to draw the line between what is and what isn't a bowline. You might, therefor, decide that any eye knot having an overhand based nipping structure is a bowline. Or, you might decide that all bowlines must have a loopy nipping structure, but no requisite bight element. It's up to you to decide. For myself, I've happily already decided to my satisfaction. At the end of it all, the knots are still what they are, and they do what they do, irrespective of the reasoning used to categorize them.     
     
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 21, 2015, 07:34:36 AM
I am progressing this project.

I see a major stumbling block being just reaching some broad consensus on the basic terminology identifying each of the key components of the Bowline structure - if we cant even reach agreement on this simple matter - then it will be near impossible to move forward.

I have created an image of the #1010 R/hand Bowline structure - showing the anatomy per Xarax proposition.

Xarax, I have labelled the various components as per your post at reply #215.  Note that I have added a comment re the 'capstan effect' around the 'Standing End'. I can delete this reference if you wish.

I am requesting that all interested IGKT members label each component and then report back in this thread - so I can collate and then post each proposition.

I need 100% clarity on this - no obfuscation.
Reference your preferred names for each component against A, B, C, D, E, F, G.

I would like to keep this professional and civil - and I will ignore responses that are vitriolic or taunting toward other IGKT members (and I hope that the site moderators will swiftly delete posts that are so deserving).

I fully respect everyone's input as supplied in good faith - and will not seek to rubbish or denigrate a contributors proposition.

I see this as the only way to progress this project - going forward.

I have added a blank (Template) .JPG image to facilitate this process...

I have also added a 'Genealogy-Template' image - direct comparison between A and B.

Mark Gommers

EDITED: I have added a further image...Carrick loop #1033 comparison to #1010

...

Per image 'Bowline_Anatomy_TEMPLATE' at position 'C' - this needs to be well defined.
For example:
[ ] is it a 'loop' ?
[ ] is it a 'nipping turn' ?
[ ] is it a 'nipping loop' ?
[ ] is it a 'gripping turn' ?
[ ] is it a 'nipping structure' ?
[ ] is it a 'circular helical nipping structure' ?
[ ] is it a 'constricting turn' ?
[ ] is it a 'collapsing turn' ?
[ ] is it a 'collapsing loop' ?

And so on...

In other words - what is the different between:
[ ] Turn
[ ] Loop
[ ] Wrap
[ ] helix
[ ] circular helix

And therefore - how is the position 'C' defined ?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Mobius on June 21, 2015, 08:41:43 AM

... I include in the Bowline family the Double Bowline, the Janus multi-bight-collar Bowlines, Dan's Y2K Locktight Loop, EBDB, EBSB, blah, blah, blah, etc.... and as you say, anything can be done with the tail part (afterwards).

Hi alpineer,

Thank you for your response. I am not fussed whether the munter bowline (like) variation I showed before is ultimately seen as a bowline or not (or how good or bad it is). I was just trying to better understand your viewpoint.

I see form the list above (which is clearly not complete, nor was it intended to be) that The "Eskimo" Bowline is missing, presumably because it has a core nub structure that is a Munter hitch style crossing knot. The Clove, Girth/Cow, Constrictor style turNips are all missing too. The only dual turNip cores you seem to allow are the double helix ones as in the Double Bowline, EBDB, etc. Please correct me if I have misinterpreted your viewpoint.

It is all interesting and one might be tempted to go one step further and state that only a simple single helix turNip is allowed. That would get rid of a lot more bowline 'pretenders'  ;D On top of that one could cull the potential bowline list by requiring that the bight collar, secured by the turNip, is truly a 'U' shape and that Myrtle (crossed), or Janus (reversed direction), style collars are not allowed ;D

I am not being very serious in that last paragraph, names like "Double Bowline", "Water Bowline" and probably even "Eskimo Bowline" seem to me to be too entrenched in bowline history for them not to be called bowlines. I believe we just have to work with history and find the right dividing line between bowline and 'bowline-like' loops.

Cheers,

mobius.





Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 21, 2015, 09:21:42 AM
   Do not forget to show the crossing point, and label the legs of the collar and of the nipping loop ( "inside" the collar and the nipping loop ).
   "Single helix", is a wrong term - because when we say "single helix" we usually mean a single-stranded helix, in contrast to a double or triple stranded one.
   "Single-turn helix", or "One-turn helix", sounds more accurate to me.

https://en.wikipedia.org/wiki/Double_helix_%28disambiguation%29 (https://en.wikipedia.org/wiki/Double_helix_%28disambiguation%29)
https://en.wikipedia.org/wiki/Triple_helix (https://en.wikipedia.org/wiki/Triple_helix)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Mobius on June 21, 2015, 11:21:48 AM
Bowline Anatomy:

D. I would slightly prefer "Outgoing eye leg". Outgoing seems better to me than Ongoing if it is to be often combined with "Returning eye leg" in the same discussion.

G. the term "Eye" to me refers to the whole elliptical loop shape, ie. like a human eye. I would probably use "Tip of the Eye" for that lower side of the eye or even just "Tip".

Bowline Genealogy:

B. "Eskimo" for me. This is what I have always known it as and I do not like the alternative particularly. "Anti" at first sounded to me as though it meant that the "Eskimo" is not a bowline. Then I thought in terms of anticyclone and thought that it meant a Left Hand Bowline. "Anti" is not quite right for me.

C. "Collar" is fine for me. Shirt collars go around necks (the vertical SPart) and this is exactly what C. does.

D. "Collar" is ok too I suppose, though the outgoing leg is not exactly the neck, is it? I don't know whether "waist band" would make better sense. Or we could talk of D. still being a "collar", however C. is a "proper collar"

E. We could talk about this "Eskimo" Bowline as one where the collar is replaced by a waist band around the outgoing leg

Cheers,

mobius
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 21, 2015, 12:36:22 PM
   I had thought of the word "ongoing" to hint that, at this part of the eye, it is advancing / continuing / unfolding, i.e. to denote the stage of the process in the forming of the eye.
   If we do not care about this meaning, I guess we should prefer two simple words which are more direct antonyms of eachother : "arriving / departing ", " coming - going ", " entering - exiting ", etc.
   It would be good if we could use the same antonyms for the legs of the collar, and for the legs of the nippping loop.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 22, 2015, 03:52:18 AM
Bowline Anatomy:

A. Standing Part
B. Collar (delete capstan reference)
C. Nipping Loop (delete helix reference)
D. Standing Part Side Eye Leg
E. Tail (End is redundant)
F. Tail Side Eye Leg
G. Eye

Additional Parts...
Stem
Crossing Point
Core/Nub

To better indicate the Eye, add a short line for each eye leg coming from the core with arrows pointing back toward base of the Eye. Indicate "Eye" in box at three separate locations.
         
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 22, 2015, 04:05:43 AM
Bowline Genealogy:

C. Collar 
D. Collar

E. They are both Collars, irrespective of what they are collaring.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 22, 2015, 07:08:42 AM

... I include in the Bowline family the Double Bowline, the Janus multi-bight-collar Bowlines, Dan's Y2K Locktight Loop, EBDB, EBSB, blah, blah, blah, etc.... and as you say, anything can be done with the tail part (afterwards).

Hi alpineer,

Thank you for your response. I am not fussed whether the munter bowline (like) variation I showed before is ultimately seen as a bowline or not (or how good or bad it is). I was just trying to better understand your viewpoint.

I see form the list above (which is clearly not complete, nor was it intended to be) that The "Eskimo" Bowline is missing, presumably because it has a core nub structure that is a Munter hitch style crossing knot. The Clove, Girth/Cow, Constrictor style turNips are all missing too. The only dual turNip cores you seem to allow are the double helix ones as in the Double Bowline, EBDB, etc. Please correct me if I have misinterpreted your viewpoint.

It is all interesting and one might be tempted to go one step further and state that only a simple single helix turNip is allowed. That would get rid of a lot more bowline 'pretenders'  ;D On top of that one could cull the potential bowline list by requiring that the bight collar, secured by the turNip, is truly a 'U' shape and that Myrtle (crossed), or Janus (reversed direction), style collars are not allowed ;D

I am not being very serious in that last paragraph, names like "Double Bowline", "Water Bowline" and probably even "Eskimo Bowline" seem to me to be too entrenched in bowline history for them not to be called bowlines. I believe we just have to work with history and find the right dividing line between bowline and 'bowline-like' loops.

Cheers,

mobius.
Eskimo, Clove, Double, Water are part of the immediate Bowline family, being constructed of simple stacked loops. And I'm OK with the extra Janus collars having pure Bowline status because a) they are simple bight collars and b) they are apres bowline extensions. But the Constrictor puts an extra "twist" into the mix, adding complexity, and so is excluded from the immediate family. The Cow is in a grey zone for me and would take more keyboard pounding to elaborate why than I care to at this time. Perhaps later.         
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 22, 2015, 10:38:45 AM
(research, then delete capstan reference)

   Research, think, then understand capstan reference !
   
(https://upload.wikimedia.org/wikipedia/commons/thumb/5/56/Capstan_equation_diagram.svg/220px-Capstan_equation_diagram.svg.png)
   
   However, I do understand that this point is perhaps not so easy to understand... We had discussed it somewhere in the long thread about the bowline, but l think it would probably be better to try to explain it once more here.
   The Standing End can not revolve freely around its axis, and the rim/tip of the collar = the curved segment of the rope which belongs to its U-turn around the Standing End, can not slide freely around it ! In other words, the two legs of the collar are not freely "communicating" to each other : the tension forces ( when they "enter" into the first leg of the collar - the T-Load ) do not simply change direction, but retain their initial size ( when they "exit" from the second leg of the collar - the T-Hold ). If the Standing End could revolve around its axis, or if there was no friction at the contact area between the straight segment of the Standing End, and the curved segment of the collar, the surface of Standing End would behave like a free revolving pulley, where the tension on the continuation of the returning eyeleg, at the point it enters into its curved path, would remain the same, at the point it exits from this path.
   However, if there was no friction at the contact area between the Standing End and the collar, the nipping loop would had to nip and immobilize a second leg of the collar loaded exactly as heavily as the first ! ( T-Hold would had been equal to T-Load ). One of the elements which characterize the ingenious, most effective locking mechanism of the bowline, is that this does NOT happen ! The second leg of the collar is loaded more lightly than the first, so the burden which the nipping loop has to carry, in order to immobilize it, is lighter : a significant portion of the tensile forces which arrive at the end of the first leg of the collar, are absorbed by the friction between those two segments, the straight segment of the Standing End, and the curved segment of the collar. Of course, the U-turn of the common collar of the common bowline is only half a turn ( φ=180 degrees ), so the effect is not so pronounced. If we add one more turn, and form a "double-turn"="Bull" collar ( of one-and-a-half turns, φ=540 degrees ), like the collar of the modified bowline on-the-bight shown at (1) and at the attached picture, we can see this effect more clearly.
   
1. http://igkt.net/sm/index.php?topic=5385.0 (http://igkt.net/sm/index.php?PHPSESSID=auj4epi8764omrhb2vplm1mbs1&?PHPSESSID=ldea5f8si9pvr40d99osi2uq00&?PHPSESSID=ldea5f8si9pvr40d99osi2uq00&?PHPSESSID=cspaoalseolf99ojej75rre686&?PHPSESSID=7g48uu2hpksbpulloaho5uo2p6&?PHPSESSID=7g48uu2hpksbpulloaho5uo2p6&?PHPSESSID=7g48uu2hpksbpulloaho5uo2p6&?PHPSESSID=7g48uu2hpksbpulloaho5uo2p6&?topic=5385.msg36008#msg36008)

P.S. To be more precise, the effective φ is larger, because, after it goes through the nipping loop, the continuation of the returning eyeleg first contacts and turns on the surface of the first leg of the nipping loop ( φ=45-60 degrees ), then of the Standing End s ( φ=180+ degrees ), and then of the same leg of the nipping loop s again ( φ=45-60 degrees ). 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 22, 2015, 10:48:34 AM
   "First" and "Second" leg of the eye / collar / nipping loop, would be OK, provided people understand the denoted temporal order : when/if the bowline is tied in-the-end, the Working End arrives first at the "First" leg of whatever, and then at the "Second" leg of whaterver. ( I had used those labels in the past, but I am not sure about how people conceive them...).
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on June 23, 2015, 03:12:46 AM
I have updated my post at reply #232.

Added image of Carrick loop #1033.

...

Also added content to assist with defining key terms.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 23, 2015, 09:50:57 AM
   "Turn" is a different thing to me, than "loop". It denotes the shape of the curved path of a line - for example, "U-turn", "S-turn". For a 360 degrees to the left or to the right, I use the term "O-turn".
   "Loop" is the structural element where the line makes a U-turn ( like it happens in the collar of the common bowline ) or a O-turn ( like it happens in the nipping loop of the common bowline ).
   Therefore, "nipping loop" is a constricting element of a knot, which is :
   1. shaped like a O-turn
   2. tensioned by both ends, more or less by the same force ( otherwise, it is a half hitch, which is tensioned by the one end - the other end is more or less immobilized )
   3. placed around one or more penetrating lines, which are nipped by its constricting action.
   "Nipping turn" is a wrong turn, because it tries to denote a SHAPE ( geometry ) that is LOADED ( dynamics ) - two things that belong to different worlds. Same for "constricting turn" and "collapsing turn" - it is better to use the term "loop" when we want to denote a structural element, and "turn" when we want to denote only its geometrical shape. For the "Turnip", used by Dan Lehman, roo made the only usefull, to me, comment he ever made : it sounds like a vegetable.  :)

 "Circular helix", or "circular helical" whatever, are, for what we want to describe, redundant terms. Helix, and helical whatever, are enough in our case. A circular helix has constant radius, and it is not conical ( increasing or decreasing curvature ) or elliptical. I do not know any nipping structure which is shaped like a conical or elliptical helix, so what is the purpose of adding the "circular" adjective ?
  We should also keep in mind that a helix may have one or more 360 degrees helical turns. However, a helix which has two 360 degrees helical turns, is NOT a double helix !  :) :) A double helix is a compound shape, made by two helices which share the same axis, the one translated in relation to the other, and perhaps somehow narrower / wider than the other.
  "Wrap" is a line which encircles an object, be it one or more segments of ropes or rods. To remain in place, it should be tensioned, so, in this, it is not much different than a nipping loop - but in the case of the "nipping loop", what tends to move and slide through is the penetrating line or object, while in the case of the "wrap" what tends to move and slide is the wrap itself.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 23, 2015, 10:06:53 AM
  Personally, I had not made up my mind about the Carrick loop - its collar is a "Myrtle"-like collar : it enters into the nipping loop for the second time through the opposite side from which it had exited from ( in a "proper" collar, it enters into the nipping loop from the same side it had exited from ). However, before it enters into the nipping loop for this secnd time, it also "collars", in a way, the ongoing / first eyeleg... This S-shaped path in between the two tensioned elements, the Standing End and the ongoing/first eyelreg, makes this Myrtle-like collar very peculiar, and perhaps the eyeknot based on it should not be labeled as a "bowline" at all. 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 23, 2015, 03:04:02 PM
(research, then delete capstan reference)

Research, think, then understand capstan reference !

My comment was meant for agent_smith. ;D

I understood capstan to be the active driven element of a rope hauling system. Seeing the photo of the holding capstans convinced me otherwise - not you're words, which I don't read :) - that a capstan can also be passive in the sense that it doesn't rotate, as is the case with a holding capstan. So, thanks for leading me to that photo, but I'm not sure extra descriptions are needed, or even wanted, when labeling parts of the Bowline's anatomy, so my "delete" comment remains for that reason.   
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 23, 2015, 03:24:38 PM
   Coincidence ! My comment was meant for agent smith, too !  :)
   It could nt be for somebody which does not read, could it ?
   For those who can read, and are interested in understanding before deleting, there is Wikipedia !
   Great invention ! ( perhaps greater than the bowline...)
   
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Mobius on June 24, 2015, 02:16:10 PM
  Personally, I had not made up my mind about the Carrick loop - its collar is a "Myrtle"-like collar : it enters into the nipping loop for the second time through the opposite side from which it had exited from ( in a "proper" collar, it enters into the nipping loop from the same side it had exited from ). However, before it enters into the nipping loop for this second time, it also "collars", in a way, the ongoing / first eyeleg... This S-shaped path in between the two tensioned elements, the Standing End and the ongoing/first eyelreg, makes this Myrtle-like collar very peculiar, and perhaps the eyeknot based on it should not be labeled as a "bowline" at all.

I agree with with xarax, this loop gives me trouble when deciding bowline, or "bowline-like".

On one level I have looked at a "Myrtle" collar and thought of it as a crossed "u-bight", therefore bowline. However the Tail of a Carrick Loop just goes on a trip before it enters the turNip again and that gives me problems.

I have much more trouble deciding the nature of a bowline based on it's structure as derived from what the Tail does (ie. what type of bight the turNip actually secures) than the nature of the turNip itself (any single or dual turNip is ok for me).

Thinking on the run here, if we get rid of "Myrtle" style collars we solve quite a few problems. By that I mean that a bowline has to obey: The first time the Tail reenters the turNip, then it has to be from the same side it left. From my own observations, I have seen plenty of loops that appear to have a turNip, yet the Tail goes 'walkabout' so much before going back into the turNip that I lose all sense of it being a bowline. Often they seem to be "Myrtle" types. (Suggestion only for Mark, have not thought this one through too much).

Cheers,

mobius

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on June 24, 2015, 03:32:05 PM
Carrick is not a Bowline of any kind.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 24, 2015, 11:28:37 PM
   The Standing End can not revolve freely around its axis,
NB : the tail CAN, and so can work as a sort of
roller bearing, which I think enables the knot
to bear cyclical loading w/o chafing, as the S.Part
pulls through --back'n'forth w/varied tension--
the not-very-tight-fitting collar, and then it
pulls/draws the tail --its initial contact part--
with it, the tail rolling, rather than rubbing across
it --hence, no chafing!  (And the draw on the eye leg
of this turNip will arrest movement sooner than later,
helping to prevent back'n'forth rubbing.)

Quote
... U-turn around the Standing End, can not slide freely around it !
In other words, the two legs of the collar are not freely "communicating" to each other :
the tension forces ( when they "enter" into the first leg of the collar - the T-Load )
...
   However, if there was no friction at the contact area between the Standing End and the collar,
the nipping loop would had to nip and immobilize a second leg of the collar loaded exactly as heavily as the first !
( T-Hold would had been equal to T-Load ). One of the elements which characterize the ingenious,
most effective locking mechanism of the bowline, is that this does NOT happen !

The second leg of the collar is loaded more lightly than the first,
so the burden which the nipping loop has to carry, in order to immobilize it, is lighter
...
This is a conjecture completely ignoring the "ingenious"
aspect of the sheepshank, where the same sort of bight-end
collar goes around . . . nothing, and yet the "first leg" being
nipped is completely adequate --and we might suppose so, too,
in the bowline.
.:.  The second leg needs less nipping-hold because the first
leg is well nipped, not because of the U-turn around a frictive
part in their connection.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 25, 2015, 11:38:05 AM
   The Standing End can not revolve freely around its axis,
   NB : the tail CAN, and so can work as a sort of roller bearing...


   I do not know what you mean by "tail" here : The fist leg of the collar as it comes "up" and out of the nipping loop, or the rim of the collar ( the curved part which follows the U-turn ), or the second leg of the collar as it goes "down" and in the nipping loop, or the "proper" tail, the Tail End ? I hope that agent_smith will soon put an end to this broken telephone game...
   What comes in contact with the Standing End, is the rim of the collar, its U-turned part. This part can not revolve freely around its axis, simply because it is curved and stiff - but also because its two ends, the two legs of the collar, can not revolve around their axes, too, because their other ends are squeezed into the nipping loop and are immobilized - and because, as I had mentioned in the P.S. of my previous post, they, too, are not straight but slightly curved segments ( they make small but not negligible 45-60 degrees turns around the the first leg of the nipping loop ).
   However, I believe that I understand what you try to say - which is NOT any revolution of any segment of the collar or the tail around its own axis ( only the Standing End could revolve around its axis, if it was not attached to the nipping loop, and if it was not stiff enough ), but a rotation around another, perpendicular, axis... In a not-very-tight-fitting collar, the rim of the collar does move, indeed, following any motion of the Standing End back and forth. And this inserts new elements into the equation, because the force by which the curved segment of the collar embraces the Standing End varies, so the friction forces between those two elements vary, and this modifies the numbers which should be taken into account in the calculation of the capstan effect... 
   I was not talking about this. I was talking about the mechanism which is responsible for the fact ( which can easily be verified ) that the tension on the first leg of the collar ( After the nipping loop ) is smaller than the tension on the second leg of the collar ( Before the nipping loop ), so the work that the nipping loop has to do, when it nips this second leg, is easier. That fact can be "explained" ( but, of course, can not described accurately ) by the capstan effect. If we do not want or wish to use any "model" of the mechanism, we can simply say that the friction around the path the continuation of the returning eyeleg follows, in each and every point of contact or turn, absorbs a portion of the tensile forces which run through it, and so the nipping loop, at its last contact with it, has an easier job to do.

  This is a conjecture completely ignoring the "ingenious" aspect of the sheepshank, where the same sort of bight-end collar goes around . . . nothing, and yet the "first leg" being nipped is completely adequate --and we might suppose so, too, in the bowline.
.:.  The second leg needs less nipping-hold because the first nleg is well nipped, not because of the U-turn around a frictive part in their connection.

   I am really surprised, that, after all those long years dealing with the bowline, you had not noticed or understood this rather elementary and obvious thing ! Unbelievable ! ( However, I suspect that you do, but you only want to say something against what I happen to say, for the sake of keyboarding !  :) Let it be. ) 
   As I had pointed in a previous post ( which you had evidently not read or you had forgotten) , in the Sheepshank, and in the Gleipnir, the mechanism is simpler - the fact that those knots manage to "work", does not mean that they "work" in the same way, or in as effectively way as in the bowline ! ! ! The proof of this, is that, in those two knots, we have tensioned lines that is either nipped at TWO points = twice ( in the Sheepshank ), or tensioned line that are twisted around each other ( inside the nipping loop ), and carry half of the load ( the famous mechanical advantage of the Gleipnir ).
 
 
   Tell us, does this not-so-grippy, sub-Gleipnir nipping loop need to be "helped by the collar" [sic sic sic] in the sheepshank?

  The Gleipnir and the Sheepshank can not work without the mechanical advantage offered by the double line, Your Brightness ! ( How did you miss this, Watson ?)  Next fake-counter-example / question, please...

  Now, you can make a one-nipping-loop Sheepshank, or a one-line Gleipnir, "work", indeed. You only need some drops of a super glue - but that effect has nothing to do with the capstan effect, so I guess I do not have to explain it.  :) :)

   There is NO need for the nipping of the first leg ! You can by-pass the nipping of the first leg ( by making the line pass outside the nipping loop, for example, while keeping the "balance" of the nub in mid-air in another way ), and yet immobilize the returning eyeleg more easily and completely, by the nipping of the second leg, and the second leg only. The nipping of the first leg does take place, of course, and does help in the mobilization of the eyeleg - but it is less "clever" and not as effective as the nipping of the second leg which, due to friction on the path of the line AFTER the nipping of the fist leg, is more lightly loaded - and that is why the Sheepshank needs TWO nipping loops, and the Gleipnir, ANY Gleipnir ( even those based on a very tight / almost jammed Clove hitch, or on a very tight / almost jammed overhand knot ) can not work without the friction between the TWO tails inside the nipping loop, or without utilizing the mechanical advantage offered by the TWO lines : there is no way we can prevent most or all of a strong tension which goes through a straight line to pass through a nipping loop ! That is why we have to nip it twice ( as we do in the Sheepshank ), or to distribute the tension on two lines, i.e., use a mechanical advantage, AND utilize the friction inside the nipping loop between the twisted around each other ends of those two lines ( as we do in the Gleipnir ).
   ONLY after the tensile forces on the continuation of the returning eyeleg have already been diminished a lot, after those three turns around not-revolving-around-their-axes elements/"capstans" ( the first leg of the nipping loop, the base of the Standing End, and again the first leg of the nipping loop ), only then the nipping loop can nip and immobilize a heavily loaded continuation of the returning eyeleg completely. Of course, a lightly loaded eyeleg can be mobilized by any other means - including a "dumb" nipping loop, which nips it before any collar, and only once.
   The collar is a fundamental element of the bowline, just because of this ! Without a collar, we have other types of eyeknots, based on tighter nipping structures, which are also secure, but not as secure as the bowline. The Pretzel loop has no collar, and it is secure, but it is no bowline !
   I believe that, on a first, superficial examination, based on a very-lightly loaded bowline, one can underestimate the role of the collar. It requires the examination of a heavily-loaded bowline, to see how much the Standing End is "supporting" the curved continuation of the Standing End, which is literally "hanged" by its neck. If there were no friction along the path of the collar AFTER its first pass though the nipping loop, the bowline would had been a much less efficient knot, and it would probably require the use of more tight, "closed" nipping structures, which would had been difficult to untie. 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 25, 2015, 12:31:16 PM
  Let me say the same thing, in other words :
 
   1. The bowline can work, even if the first leg of the collar is not nipped ( if we "prevent" or "protect", somehow, the first leg of the collar from the nipping action of the nipping loop ).
   2. The bowline can not work, if only the first leg of the collar is nipped, once, and there is no friction on the line AFTER the first leg of the collar.
   3. The bowline can not work, if only the second leg of the collar is nipped, once, and there is no friction on the line BEFORE the second leg of the collar. ( Cases 2 and 3 are equivalent ).
   4. However, the bowline can work, if only the second leg of the collar is nipped, and there is friction on the line BEFORE this second leg, in between the first and the second legs of the collar.

   To me, those 4 things say that :
    1. ( If there is friction on the line between the first and the second legs of the collar )
    A. the bowline can work if the second leg of the collar is nipped, but the first leg of the collar is not.
    B. the bowline can not work, if the first leg of the collar is nipped, but the second leg of the collar is not.
    Therefore, the nipping of the second leg of the collar is more effective than the nipping of the first leg of the collar - because, ceteris paribus, the former can work without the latter, but not vice versa.
   
    2. ( If there is no friction on the line between the first and the second leg of the collar)
    C. the bowline can not work, if only one leg of the collar is nipped.
    Therefore, the friction between the first and the second leg of the collar is important, because, with the help of it, the bowline can work in one case : the A case above.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 25, 2015, 04:22:18 PM
  There is a simple way we can evaluate/measure how much friction is present along the path of the continuation of the returning eyeleg at the collar area, and how much this friction reduces the tension running through this line, in the segment of the Standing Part between the first and the second leg of the collar ( so, how much easier the job of the nipping loop becomes, when it nips the second collar ). We can place a ( green  :) ) freely-rotating pulley ( a "lashing block" ) on the point shown by the black arrow, at the attached picture. Now, in order to have a stable, static knot in mechanical equilibrium, and because the two legs of the collar "ABOVE" the nipping loop are equally tensioned ( the freely rotating pulley does not only eliminate any friction at the area where the Standing End would had been in contact with the collar s U-turn, but it also plays the role of equalizer of the tension running through the two legs of the collar ), they should be equally nipped as well.
   I claim that this "bowline" would be less efficient than a common bowline : moreover, it would be less efficient even from the less efficient Gleipnir, because the two penetrating the nipping loop lines are neither deflected from their straight paths nor twisted around each other, as it happens in the Gleipnir.
   It is this effect of the reduction of the tensile forces along the length of the collar, that I try to "model' with the help of the capstan effect.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 25, 2015, 09:12:18 PM
   The Standing End can not revolve freely around its axis,
   NB : the tail CAN, and so can work as a sort of roller bearing...


   I do not know what you mean by "tail" here :
Just what I wrote : "the tail" --that is, the very end part
that of all 4 parts of the eye knot is unloaded.  When the
S.Part pulls hard against the normal positioning of the tail
in usual tying, it pulls the tail towards the collar a little,
in tightening the turNip --and the tail in moving
will *roll* with this *punch*, a little : surfaces that are
in contact will remain so until rolling out of contact.
(The normal loading of a mooring line probably comes
in relatively not-go-great quantities and so doesn't
strain things beyond the comfortable circumstance
in which this simple rolling occurs.)
(This is an aspect that the tail-outside bowline lacks,
although one could position the tail so that it might
occur, anticipating the draw of the S.Part upon it.
The tensioned eye leg of course cannot rotate,
as you note.)

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 25, 2015, 09:46:08 PM
  Let me say the same thing, in other words :
   2. The bowline can not work, if only the first leg of the collar is nipped,
 once, and there is no friction on the line AFTER the first leg of the collar.
And yet it does, in the sheepshank and bellringer's loop (#1147)
insofar as friction seems the issue --instead, there comes
the problem of stability/balance.  You, yourself, explored this sort
of brief structure, and presented doubled nipping loop to achieve
better stability.  (For the simple structure --just a bight & turNip--,
it seems that positioning the tail-end opposite the S.Part,
so the loaded tail-side of the eye lies between; if this part
is elsewhere, there seems a quicker capsizing action ... .)

One might experiment by using some tubes of metal/plastic
to give "no friction" at certain points.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 25, 2015, 10:27:20 PM
When the S.Part pulls hard against the normal positioning of the tail in usual tying, it pulls the tail towards the collar a little, in tightening the turNip --and the tail in moving will *roll* with this *punch*, a little

   OK, I see what you mean. Yes, the Tail End can revolve freely around its axis, but the Standing End can not - the "model" of the bowline I had tried to paint explains the fact that there is a not negligible reduction of the amount of tension running through the line, between point A, at the start of the first leg of the collar, just after it exits from the nipping loop, and point B, at the end of the second leg of the collar, just before it enters into the nipping loop for a second time. In its path from A to B, the continuation of the returning eye leg turns around the rim of the nipping loop, then around the Standing End, and then around the rim of the nipping loop again, and in all those arcs  we have friction, and absorption of tension. If in all those points the line could slide freely, or if those point belonged to freely revolving, around their axes, elements, the bowline would had been a much less efficient eyeknot. That was my point about the capstan effect - but the crux of the matter is the presence of friction at the area around the collar, which facilitates  the job the nipping loop has to do regarding the second leg of the collar. ( And, of course, the reduction of the tension when the nipping loop nips the first leg of the collar also reduces the burden it has to carry when it nips the second leg of the collar, but this is obvious - what is not obvious, is that the friction AFTER the first nipping, and BEFORE the second nipping, does play an important role - and it is what makes the bowline s locking mechanism more efficient than the Gleipnir.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 25, 2015, 10:56:59 PM
  Let me say the same thing, in other words :
   2. The bowline can not work, if only the first leg of the collar is nipped once, and there is no friction on the line AFTER the first leg of the collar.
And yet it does, in the sheepshank and bellringer's loop

  No, it does NOT - and the proof of that is that, in the Sheepshank, we need TWO nipping loops, and in the Gleipnir, we need some deflection, and some twisting, so additional friction, between the two tails - and even with those tricks, those knots are  NOT as secure as the bowline ! Of course, under light loading, it does ( but then, as anything does, and anything goes...) - I am always speaking about heavy loading, where the locking mechanism of the bowline reveals its superiority over more simple, direct locking mechanisms, as in the cases you mention ( which can NOT withstand such loading ! )
   An eyeknot based on a locking mechanism with a nipping loop but without a collar is a bowline so badly amputated, that I find it difficult to call it "bowline" any more... And by a "collar", I do not mean a "collar-like" mid-air U turn, as the turns of the Sheepshank - AND I do not mean a "collar-like" turn around a freely revolving element ( which would behave like a freely rotating pulley or a bearing ). I mean a collar with friction - and such a collar behaves in a way which, IMHO, can be modelled, and somehow explained, by the reference to the capstan effect. Of course, the REAL situation is much more complex - but I thought that the capstan effect can explain, in a simplified yet satisfactory way, the simple fact that the second leg of the collar, when it comes out of the nipping loop, is less tensioned than the first, just before it goes into the nipping loop again.   

One might experiment by using some tubes of metal/plastic to give "no friction" at certain points.

   I did, but not under the completely controlled, "laboratory" conditions I would had wished... What I had also seen, was yet another very interesting thing, which I had mentioned some time ago, in the long thread about the bowline : that the reduction of friction between the nipping loop and the one or both legs of the collar, has an unexpected effect : the nipping loop can "walk" towards the tip of the eye ! Therefore, the collar, and the friction around it, is not only needed to stabilize the nipping loop, and prevent it from opening up and degenerating into an open helix, and to reduce the tensile forces which arrive at the second leg of the collar, but also to prevent the "walking" of the nipping loop towards the tip of the eye. So much for the "secondary" role of the bowline s collar !
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on June 28, 2015, 05:05:18 AM
  Let me say the same thing, in other words :
   2. The bowline can not work, if only the first leg of the collar is nipped once, and there is no friction on the line AFTER the first leg of the collar.
And yet it does, in the sheepshank and bellringer's loop

  No, it does NOT - and the proof of that is that, in the Sheepshank, we need TWO nipping loops, and in the Gleipnir, we need some deflection, and some ...
And it's all nigh impossible to test empirically,
for the imbalances pointed to and necessary
countering somehow.

But the assertion "2" is just plain wrong :
necessary friction is a matter of material (you cannot
idealize this!), and we've seen strange things
when it's greatly reduced via HMPE cord (and
its great strength, though IIRC the slippage comes
in sub-super force range), and can certainly know
that in the other direction (frictive) there will be
much less need of structure built upon structure.

But, yes, I've seen constrictor knots get loose(r)
over time, though they are well-nipped.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on June 28, 2015, 12:05:02 PM
  Let me say the same thing, in other words :
   2. The bowline can not work, if only the first leg of the collar is nipped once, and there is no friction on the line AFTER the first leg of the collar.

  "2" is just plain wrong

  "2" is just plain correct, and obviously true ( and equivalent to equivalently and plainly correct and obviously true point 3., stated afterwards ) - because, otherwise, we would nt use any collar at all !  :) :) However, I believe that you simply had not understood the sentences of points "2" and "3" - perhaps because you had not noticed the word "once", or perhaps because they are not written correctly - their meaning is unambiguous, and can not be argued...
   
   Now, I see that the rather simple "thought experiments" ( Gedanken-experiments ) I had suggested were not, for some people, such easy things to "perform" as I had thought they would had been... OK. Then, I will try to say the same things otherwise - and in a form one can verify or falsify, with the help of a "real" experiment !  :) :)

   Let us tie two bowline-like knots, like the knot shown in Reply#252, and at the attached picture. In those knots, we can either use freely rotating pulleys / "lashing blocks", to simulate the absence of friction along the line of the collar, or use not-rotating pulleys ( where the axes of the pulleys are "glued", so the lines "feel" friction, as they slide along the grooves of the pulleys ), to simulate the presence of friction at the area of the collar.
   Moreover, in each of the two cases ( the case without friction, and the case with friction ), let us do one more differentiation : let us "isolate", from friction, the first, only, leg of the first "bowline", and the second, only, leg of the second "bowline", at the points where they go through the nipping loops, by the device described here :
   
   One might experiment by using some tubes of metal/plastic to give "no friction" at certain points.
   ( This "isolation" from friction inside the nipping loop may be complete or partial - in the later case, we may just reduce the friction forces around the first leg or the second leg by, say, 50%, so we would have the 100% of the "normal" friction around the one leg and the 50% around the other leg - I describe only the 100% - 0% situation, for clarity ).

   So, we have FOUR different cases :
   1a. No friction along the collar line - friction at the first, only, nipping point, before the first leg - no friction at the second nipping point, after the second leg.
   1b. No friction along the collar line - no friction at the first nipping point, before the first leg - friction at the second, only, nipping point, after the second leg.
   2a. Friction along the collar line - friction at the first, only, nipping point, before the first leg - no friction at the second nipping point, after the second leg.
   2b. Friction along the collar line - no friction at the first nipping point, before the first leg - friction at the second, only, nipping point, after the second leg.
   
   WHICH bowline-like eyeknots will hold more, in each case, in an tug-of-war type experiment ?
   The evaluation I had claimed of the less efficient, secondary, "dumb" way the first leg is nipped, in comparison to the more efficient, "clever" nipping of the second leg, was based on the answer of those experiments.

   1a is as efficient as 1b.
   It does not matter WHERE a line is nipped, if it is nipped once, and there is no friction anywhere else !
   
   2a slips first=less secure than 2b.
   Nipping, once, only after the second leg of the collar, is more efficient / "clever" than the "dumb" nipping, once, only before the first leg of the collar.

   1a slips first=less secure than 2a.
   1b slips first=less secure than 2b.
 
Friction along the first leg of the collar, along the rim of the collar, and along the second leg of the collar, does matter !
   Clear as mud ?  :) :) :) I can do no more/better !  :( :( :(
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Tex on July 11, 2015, 09:23:13 AM
Hi a_s

I just scanned through to suggest adding the bowline on a bight with one loop pulled up, just to find someone beat me to it, so good.

I'll just point out the obvious, that you don't have to tie it that way, either TIB or in the end. You can start with the loop already short-circuited. IMO Compared to some of the creative abcdedbd bowlines it's not a complicated retuck tied in the end even. At least you have a map in front of you and when you're done it's easier to verify than some double reversed-reeved pretzel hitch bowline with a yosimite finish.

Speaking of which, I'm not sure if any pretzel-nip bowline has made the list yet, for what it's worth.

I also thought it could be nice to show the TIB method for at least the BotB and point out that basically the same method can be used to produce any number of single or double (or transformed) bowlines starting with any number of single or double nipping structures (and a simple retuck comes along for the ride).  Of course it's not a tying guide, so, maybe not...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 16, 2015, 01:34:57 PM
Another Eye Knot (Bowline based around the so-called 'Myrtle maneuver' - I hate that moniker) that I finally found time to photograph (in better quality than my previous attempt)...
Note: I used the term myrtle manoeuvre, and not 'collar'

Its just a modification of one of Alan Lee's brilliant existing work.

No other comments from me at this point in time.

Quote
I'll just point out the obvious, that you don't have to tie it that way, either TIB or in the end. You can start with the loop already short-circuited

Tex, have you got any photos or diagrams to lend assistance? I am struggling with work (in real life) and other issues at the moment. An uphill battle for every step forward..

Quote
Speaking of which, I'm not sure if any pretzel-nip bowline has made the list yet, for what it's worth.

Working on it... time is against me at the moment (sorry).

Mark Gommers
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: xarax on July 16, 2015, 03:09:33 PM
   There is no Myrtle collar here ! The first leg of the collar exits from the nipping loop from the same side the second leg enters into - as it happens in the "proper" collar, of the classic bowline.
   The main disadvantage of this eyeknot is that the "Tail Part" ( = the last part of the Stranding Part, before it exits the nub and becomes the Tail End ) is not secured very tightly : First, it passes through the centre of those two interlocking loops (  the main nipping loop and the loop of the "link" ), where it is "protected" rather than squeezed by the surrounding segments, which act more like a cocoon ( an armour ) rather than constricting structure ( a corset  :) ). The stiffness of the climbing ropes make this central opening a "soft" spot, a segment which we need to secure tightly should rather avoid. (*) Second, it passes through through the bight of this very round and very wide collar almost freely...
   However, it does have a great advantage, which makes it interesting, and which should always be explicitly mentioned, and appreciated. It is TIB. (1)

(*)
  The central opening of this ... knot, contrary to what one might had expected, is not nipping the tail as hard as I would like to... I believe that, in this tight entanglement of the two rims and the four limbs of the two nipping loops < ( the main nipping loop, and the nipping loop of the "link" ) >, a great portion of the tensile forces that would otherwise tend to shrink the diameter of the central opening and grip the penetrating tail forcefully, is "wasted" - it is absorbed by the strong friction forces between the many tightly embracing rope segments that turn around the central opening, and around the penetrating tail that is supposed to be nipped.

1. http://igkt.net/sm/index.php?topic=4695.msg30329#msg30329 (http://igkt.net/sm/index.php?topic=4695.msg30329#msg30329)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Tex on July 19, 2015, 01:51:09 PM
agent_smith:
Quote

(quoting Me:)
Quote
    I'll just point out the obvious, that you don't have to tie it that way, either TIB or in the end. You can start with the loop already short-circuited

Tex, have you got any photos or diagrams to lend assistance? I am struggling with work (in real life) and other issues at the moment. An uphill battle for every step forward..

A_S it's not a big deal to me.  Tied in the end, I think it's obvious how to short circuit the second loop, when you start retracing the bowline, taking the end around the main loop(s) the second time, you just go around as little as possible (and not through your harness for example).

as for tying the BoB in the bight,
normally, as a baseline instruction set for your reference, so you understand me, you
1) fold rope in half
2) make nip with both lines together
3) pull tip of double-folded rope through nip a little and do the collar manoeuvre with it.

To short circuit one loop instead, step 3 becomes:
3) pull a bight from ONE SIDE of double folded rope through the nip and do the collar manoeuvre with it.

You should pull that bight from as close to the nip as possible.

I think you should prefer to pull the bight  from the side related to the tail, not to the standing end, but it probably doesn't matter much, just adds that much more security to the tail.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on September 23, 2015, 02:19:20 AM
Still progressing this work...one step-at-a-time.

Part of the paper will include a discussion on knot terminology/anatomy.

I have attached a scoping document to obtain opinion on correct terminology for each structure/segment/part of a knot structure.

I would appreciate any replies.

Format for reply would be:

[ ] A  your answer
[ ] B  your answer
[ ] C  your answer
[ ] D  your answer
[ ] E  your answer
[ ] F  your answer

You may choose from the list of descriptors provided (or feel free to add your own) and so on...

Hopefully the image is readable (difficult to get reasonable image quality with 100KB size limit)

Thanks,

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on December 28, 2015, 07:18:57 PM
Well, not wishing to contradict Xarax, but this

(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=18912;image)

certainly looks like a Myrtle core to me, with the tail reworked into a collar around the load line and tucked through the double nipping loops of the Myrtle.

How can anyone not see the simple Myrtle core?

@Mark  do you find any significant advantage from the final tuck under the collar?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on December 28, 2015, 07:36:45 PM
Follow the shading
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Mobius on December 29, 2015, 03:50:34 AM
Follow the shading
xarax notes earlier that the knot is TIB, this being the advantage of the final tuck. xarax also discusses that the final tucks are not tight. For this reason the knot does not load very well in my opinion, I trialled this knot a few months ago along with two other TIB loops of a slimilar a vain. Load sharing wise the last few tucks do very litlle and the knot, though secure, distorts (it kind of rolls) too much for my liking.

Cheers,

mobius
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on December 29, 2015, 12:04:45 PM
Hi Mobius,

Unless TIB has changed its meaning since last I was on here, it means tied without access to the ends, which would totally preclude the ability to make 'the final tuck'.

The other alternative would be to tie the knot 'with' a bight which effectively forms a doubled knot, which this clearly is not.

If we ignore the diversion of the collar and final tucks of the end, this is simply a Myrtle Loop knot.  The Myrtle resolves to the basic knot form of 5,1 and it is impossible to make the 5,1 'in bight' resorting only to our rather restricted three dimensional space.

Dependent upon the cordage, the Myrtle can range from the most exquisite simple little knot, to a rather risky beast.  despite having two counter locking nipping loops, it has nothing else to keep the nipping loops working.  The slightest slack induced into the knot and the whole thing can fly open if unloaded.  The final embellishment however, of wrapping the end to make another nipping loop (albeit non loaded), makes a significant difference to the knot stability.

I find this ammendment  to the Myrtle loop to be a significant improvement, hence my question to Mark to see if he had similar experience.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on December 29, 2015, 08:49:54 PM
Unless TIB has changed its meaning since last I was on here,
it means tied without access to the ends,
which would totally preclude the ability to make 'the final tuck'.
Then try the reverse : UNtying w/o access to the ends.
I think that you'll be able to do this, and change your mind!
 ;)

Quote
Dependent upon the cordage, the Myrtle can range from the most exquisite simple little knot, to a rather risky beast.  despite having two counter locking nipping loops, it has nothing else to keep the nipping loops working.  The slightest slack induced into the knot and the whole thing can fly open if unloaded.  The final embellishment however, of wrapping the end to make another nipping loop (albeit non loaded), makes a significant difference to the knot stability.

I find this ammendment  to the Myrtle loop to be a significant improvement, hence my question to Mark to see if he had similar experience.
I prefer the anti-bowline similar knot (bring tail
into S.Part's turNip from the opposite side/direction),
and finish by tucking the tail out closer to the eye
--the Myrtle tucking out away ... .
AND put in a 2nd tail-wrap. for added security and that
3rd (better *rounding*) diameter in the turNip's grasp.
(But this isn't TIB..)

And, yes, one can add in a collar to such things (to which
Agent_Smith is bound to Yosemite-tuck the tail!   ;D  ).


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on December 29, 2015, 11:50:58 PM
Well, today, thanks to Dan, I was treated to a surprise.

I tied the knot exactly as per the image - a Myrtle plus an extra wrap and tuck.

Then I fixed the ends and started to decompose the knot.  It progressed nicely and rapidly to - The Unknot...

So, I stand corrected - this knot can indeed be TIB.

More research needed...

Thanks Dan - I think!

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on December 29, 2015, 11:55:11 PM
Derek the dunny man returns!

Quote
@Mark  do you find any significant advantage from the final tuck under the collar?

This Bowline variant intrigues me.
Am still unsure of its proper name?? Xarax used the 'link bowline' term I think...? I remain unclear of the significance of 'link' in the descriptor... maybe someone can chime in to assist with the background to the choice of terms for naming this structure?

I also think the knot structure is largely attributed to Alan Lee - as it shares much of the wonderful 'Lee Zep X Bowline' structure - but then deviates in how the tail is maneuvered.

It ticks a few boxes for me:
[ ] stable
[ ] secure (which also includes slack shaking security)
[ ] resistance to jamming
[ ] verifiable (like any knot - you need to learn how to tie it and then develop pattern recognition skills)

and... it has 3 rope diameters inside the 'nipping loop'. Proponents of this theory suggest that the MBS of the knot is raised because the radius of the SPart as it enters the core/nub of the knot is increased.

I have not yet 'field tested' the knot in actual climbing or rescue applications.

But I do like it - and it certainly is deserving of further study.... perhaps a candidate tie-in knot for CTOMS with their 6.0mm technora cord?

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on December 30, 2015, 12:00:01 AM
From Dan...
Quote
Then try the reverse : UNtying w/o access to the ends.
I think that you'll be able to do this, and change your mind!

Yes - indeed.

I have found that 'reverse engineering' a knot by untying it step-by-step (without access to any end) is a valid tool to assess whether it is 'TIB'.

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on December 30, 2015, 11:47:04 AM
From Dan...
Quote
Then try the reverse : UNtying w/o access to the ends.
I think that you'll be able to do this, and change your mind!

Yes - indeed.

I have found that 'reverse engineering' a knot by untying it step-by-step (without access to any end) is a valid tool to assess whether it is 'TIB'.

Mark

Indeed, I often use the technique when seeking components or tying methods, but finding that a collar and a tuck could turn a 5,1 knot into an Unknot was quite a shock.  In hindsight, perhaps it should not have been such a shock, because I can tie the 'Slipped' Myrtle Loop TIB.  I put slipped in single quotes because it refers more to the tying method than the final knot itself which is most definatley not 'slipped'.  I don't know if you use the Constrictor method for tying the Myrtle or not, but I fold a Constrictor, pass the Wend around the fixing point, then pass the end into the Constrictor.  Then I collapse the Constrictor with its contained 'end' and it winds itself into the Myrtle.  However, if I am making it TIB, then I fold the Constrictor, but, instead of the end, I pass a small bight through the constrictor.  When this is collapsed, it likewise gives an extra wrap, plus four diameters through the nips.  For me the advantage if making the knot this way is economy of cord.  I only cut the cord after the knot is complete, rather than having to guess the required cord length before tying.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on December 30, 2015, 12:56:17 PM
Derek the dunny man returns!
snip...

Mark

LOL, No Mark. I never went away, I just CBA with being told endlessly that my opinion was wrong.

But back to the 'knot in hand'.  For me a Bowline is a loopknot with a loaded nip and a partially loaded, nipped stabilising collar.  I am sorry, but I just cannot bring myself to include every loop knot that contains a nipping turn into a giant family of Bowline-esque knots.

The knot in hand, yes, it is a loop knot, and yes, it has a loaded nipping turn, but it's claim to being a Bowline, for me, ends there.  Instead, it's function is derived from a second co-nipped nipping loop.  Together, these two co-stabilising nipping loops constitute the functional heart of this knot  The amendments of an unloaded collar and a third wrap to give a tucked, nipped end, enhance the durability of the knot, but do not change its core functionality of co-stabilising twin nipping loops.

Dave Root spotted this basic knot in the wild quite some time ago now, holding up a Myrtle Tree, and after some discussion it was given the name of Myrtle Loop knot.  Unashamedly, I plagiarised the name to call the self-stabilising twin nipping loops a Myrtle C Component, where the 'C' denotes it as a compound component.

I have known this knot from my childhood on the farm, but like so many knots in use, it did not have a name.  However, one thing was for sure, tied in hairy bailer twine, it did not so much 'jam', rather, with a couple of sharp snaps, it virtually fused...  over time, with weather and abuse of use, you might be forgiven for thinking it to be some form of organic splice.  But then, that was down to the cordage, I have also seen it slither open as if it were some living snake when made with some nice firm shiny polyester braid.

Unfortunately, all the attributes you ascribe to it, even in this 'embellished' form, are essentially dependent upon the cordage it is made in, and with the array of climbing ropes growing in profusion, classifying a knot without reference to its cordage might soon become a dangerous process.

I have not tried the new 6mm Technora cord yet, but I do have some cord samples that I would only trust in very long splices, they just flow so easily under load.  They just seem immune to frictional amplification via turns and nips...

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on December 30, 2015, 05:04:58 PM
Well, that really is quite amazing.

(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20262;image)

I have confirmed that the Myrtle C Component at the heart of this Myrtle Loop knot is a 5,1.

Yet only one tiny modification is necessary to destroy this, and render it into the Unknot.

It is not the collar, nor the tuck under the collar.  Just the action of passing the end back into the nip, means that this knot can then be be TIB.

Well done Xarax...  I bow to your observation.

However, have you been able to reverse the reversal, and create the knot 'In Bight' so to speak?

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Mobius on December 31, 2015, 01:10:15 AM
Derek the dunny man returns!
snip...

Mark

LOL, No Mark. I never went away, I just CBA with being told endlessly that my opinion was wrong.

But back to the 'knot in hand'.  For me a Bowline is a loopknot with a loaded nip and a partially loaded, nipped stabilising collar.  I am sorry, but I just cannot bring myself to include every loop knot that contains a nipping turn into a giant family of Bowline-esque knots.

The knot in hand, yes, it is a loop knot, and yes, it has a loaded nipping turn, but it's claim to being a Bowline, for me, ends there.  Instead, it's function is derived from a second co-nipped nipping loop.  Together, these two co-stabilising nipping loops constitute the functional heart of this knot  The amendments of an unloaded collar and a third wrap to give a tucked, nipped end, enhance the durability of the knot, but do not change its core functionality of co-stabilising twin nipping loops.

Dave Root spotted this basic knot in the wild quite some time ago now, holding up a Myrtle Tree, and after some discussion it was given the name of Myrtle Loop knot.  Unashamedly, I plagiarised the name to call the self-stabilising twin nipping loops a Myrtle C Component, where the 'C' denotes it as a compound component.

I have known this knot from my childhood on the farm, but like so many knots in use, it did not have a name.  However, one thing was for sure, tied in hairy bailer twine, it did not so much 'jam', rather, with a couple of sharp snaps, it virtually fused...  over time, with weather and abuse of use, you might be forgiven for thinking it to be some form of organic splice.  But then, that was down to the cordage, I have also seen it slither open as if it were some living snake when made with some nice firm shiny polyester braid.

Unfortunately, all the attributes you ascribe to it, even in this 'embellished' form, are essentially dependent upon the cordage it is made in, and with the array of climbing ropes growing in profusion, classifying a knot without reference to its cordage might soon become a dangerous process.

I have not tried the new 6mm Technora cord yet, but I do have some cord samples that I would only trust in very long splices, they just flow so easily under load.  They just seem immune to frictional amplification via turns and nips...

Derek
Hi Derek,

Interesting background knowledge regarding the knot's name, thank you.

If you are interested,  my recollections of the TIB knot Mark shows was that under load the final tucks definitely do add structure to the linked component  and the knot was secure and stable after rolling a little. Rolling sounds bad, however 'leans over' might be a better description. I have some images at home which I could share after my holidays.

Cheers,

mobius
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on December 31, 2015, 10:26:08 AM
Hi Mobius,

I hope the holiday is going well, back here in England we are 'enjoying' seemingly perpetual rain and wind, and I don't mean the wind occasioned by Christmas sprouts and chestnut stuffing.

Yes, I would be interested in your findings on this structure, but please do not forget to include the nature of the cordage used in your tests.  With this knot, it matters....

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 02, 2016, 11:54:52 AM
Something else I'd like to add is that this knot is (in my opinion) well suited as a tie-in knot for lead climbing / mountaineering activities. It is a more 'efficient' eye knot than my other tie-in knot... the EBSB Bowline. It also meets Xarax's preference for no sharp turns within the structure (ie there are no sharp U turns or full turns of the working end around a single rope segment/cross-section as it winds its path to conclusion).

Quote
I am sorry, but I just cannot bring myself to include every loop knot that contains a nipping turn into a giant family of Bowline-esque knots.

The knot in hand, yes, it is a loop knot, and yes, it has a loaded nipping turn, but it's claim to being a Bowline, for me, ends there.

This of course depends on what your definition of a 'Bowline' is.

Per Dan Lehman, the key component of all Bowlines is the 'nipping turn' (which Dan likes to refer to as a 'TurNip'). A poll was taken on this some time ago and the consensus view was 'nipping loop'. While I am not a parrot - and certainly knot parroting Dan... I have considered his proposition and concur.
The 'nipping loop' is loaded at both ends and compresses all material encircled within its helical structure. The absence of a nipping loop excludes other eye knots (eg #1047 F8 eye knot) from the Bowline family. The collar is also an important component - and it must not experience load - to the extent that it is likely to jam. Indeed, when untying a Bowline that has been under very high load, it is the collar that is the easiest segment to manipulate initially when untying. The nipping loop (which must be loaded at both ends - the SPart providing 100% of the initial entry load and the ongoing eye leg providing the opposite 50%) + the collar, together are the structural requirements to fulfill the definition of a Bowline. The 2 components are holistically paired.
NOTE: This is my view of a Bowline - and it captures the essence of Constant Xarax and Dan Lehman...:
[ ] Dan Lehman: The nipping turn is the essence of all Bowlines
[ ] Constant Xarax: All Bowlines have a collar structure (he also posited that a nipping loop must be loaded at both ends - the SPart at 100% and the ongoing eye leg providing the other 50%).

I think the IGKT still cant agree on the nomenclature of a knots structure - evidence for this is that several IGKT members still use their own names - and they appear to all differ.

Ashley places Bowlines in the category of 'loop knots' - and yet, there has been some general consensus that 'eye knots' is a better descriptor. Support for use of this descriptor can be found with eye bolts and eye splices. For example, would an eye bolt be better described as a loop bolt and an eye splice renamed as a loop splice?

Quote
Instead, it's function is derived from a second co-nipped nipping loop.  Together, these two co-stabilising nipping loops constitute the functional heart of this knot
I respectfully disagree that there are 2 nipping loops in this knot. The second 'loop' which you refer to is not loaded at both ends and so it does not fit the definition of a 'nipping loop' [loaded at the SPart end and loaded at the Ongoing eye leg end].

Since this knot also has 3 rope diameters captured within the nipping loop - it might be a candidate tie-in with 6.0mm technora cord (ie the CTOMS 'TRACE' system).
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 02, 2016, 06:54:15 PM
Hi Mark,

I would not dream of contradicting anyone's opinion, and this is very much the area of these comments.  Hopefully though we can constructively debate our various perspectives in order to better understand each others basis for their stances.

I would agree that making this knot is very efficient, especially if using the Constrictor fold method, followed by a wrap and a re-tuck to form the collar and the final third diameter in the nip.

I think there is room to debate the term 'sharp', as the loaded line executes a full 360 degree turn (around 3 diameters) and is loaded 100% one side and -50% the other, unlike knots at the other end of the spectrum such as the Fig 8 where the loaded line executes several partial turns, gradually transferring force in the process.  For me, the term 'sharp' also contains an element of 'concentration'.  In the 8, load is transferred through a series of segments, through a series of cords, from the load cord to the two loop cords.  Transfer is 'distributed' over quite a length of cordage.  However, in the Myrtle, the load is born in a single component, the 'Turnip' as Dan would have it.  100% load is applied one side, then 360 degrees later it meets -50% loop load and in the passage around the nip. it meets the other -50% from the return leg of the loop.  There is massive meeting of force here in this single small component featuring little more than 9 diameters length of cord.  This, combined with the distortion from a full 360 degree tight turn, is, for me, a recipe for cord failure, and is a more rational consideration of the function of this component than to resort to the use of disputable terms such as 'sharp'

This of course depends on what your definition of a 'Bowline' is.

Indeed, Dan does hold that the 'Key' component of the Bowline is the nipping loop,  However, how he manages to argue that, in a two component knot, either of the two components is more 'key' than the other, I do not know.  Certainly, the Turnip is the major load processing component, but we must not dismiss the load processing function of the collar, even though I do acknowledge that the major function of the collar is to stabilise the orientation of the Turnip.

While I concede that knots without a 'Turnip' should not be classified as Bowlines, I equally insist that knots without a structurally stabilising collar likewise cannot be classified as a Bowline.

Ashley places Bowlines in the category of 'loop knots' - and yet, there has been some general consensus that 'eye knots' is a better descriptor.

' When is an Eye not an Eye?  Answer - When it is a loop...'

Obviously, both an Eye, and a loop are both loops, but, while all Eyes are loops, not all loops are Eyes...  While a tiny loop only one or two diameters across can be safely be referred to as an Eye, a large loop tens or hundreds of diameters across does not really lend itself to being called an 'Eye'.  Where is the grey zone when a loop also becomes an Eye?  I don't know, but I would feel a bit daft calling a loop of more than 5 or 6 diameters and Eye.

So, as the Bowline functions with any sized loop, it is clearly a 'Loop knot' that can also be made right down to Eye knot size.  So, once again, I am with Ashley on this one.  The Bowline is a Loopknot...

I respectfully disagree that there are 2 nipping loops in this knot. The second 'loop' which you refer to is not loaded at both ends and so it does not fit the definition of a 'nipping loop'

I would agree with you on this one were it not for the fact that a nipping loop does not have to be externally loaded on both ends in order to function.  For a nipping loop to function, all that is required is for one end to be secured, the round turn frictional amplification is then sufficient to transfer the applied load into the nipped core.

This end gripping function is achieved in the Myrtle because each Turnip grips and holds its companion once the knot is dressed and set.

By way of demonstrating this argument, consider the Constrictor, a two turn nipping loop arranged to self nip and hold its ends.  After dressing and setting, neither end requires any load application for the nipping loops to function perfectly.

Perhaps we could look a little closer at your definition of 'Nipping Loop'

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 03, 2016, 02:06:57 AM
Derek, I have amended my previous post to include explanatory notes to further elaborate on my proposition. In particular, the reference to sharp U turns and other turns which force the rope into tight radius turns... I should have been clearer to point out that it is sharp turns around a single rope diameter/cross section. This is what Xarax did not like - turns around 2 or more rope diameters were viewed as preferable. For example, the 'Yosemite finish' to secure a Bowline forces the 'working end' to wind around a single rope diameter.

The presence of a nipping loop (loaded at both ends) is a key concept - advanced by Dan Lehman.

The presence of a collar structure - is a key concept advanced by Constant Xarax (he actually used the term 'proper collar' - which I think meant to include the concept of a 'capstan effect' created as the collar makes a 180 degree U turn around the SPart).

Xarax also posited that the nipping loop must be loaded at both ends:
[ ] one end is formed from the SPart
[ ] opposite end is formed from the 'ongoing eye leg'.

The concept of an 'ongoing eye leg' and a 'returning eye leg' was advanced by Xarax.

The opposite end of a nipping loop must have load supplied by the ongoing eye leg.

I think Xarax was trying to tell us that the nipping loop acts to compress material captured within the helix - that is, it is a compression zone.

Following this strict definition, the second nipping loop which you referred to in the 'Myrtle/link Bowline structure' is not loaded at each end by the respective SPart and the ongoing eye leg.

Dan Lehman examined #1033 (Carrick loop) - to see if it would fit the definition of a Bowline.
#1033 has a collar structure and it has a nipping loop that is loaded at both ends. The source of one end is the SPart and the source of the other end is the ongoing eye leg. There is also a collar structure.

This in my view fulfills the definition of a 'Bowline'.

Ashley of course did not examine these structural components in detail as is now done in the 21st century at the IGKT. Ashley was content to catalog as many knots as he could using the resources available to him at that time in history. We now have the benefit of social media to connect many minds from around the world - something that Ashley did not have the benefit of. We are now able to dig deeper and examine structural details of knots that Ashley did not contemplate.

I think this subject definitely remains open for healthy debate - it is far from a complete theory.

I wish Xarax would weigh in with his comment...

...

Quote
Where is the grey zone when a loop also becomes an Eye?  I don't know, but I would feel a bit daft calling a loop of more than 5 or 6 diameters and Eye.

I dont believe that scale enters into the definition of an 'eye'.
In my view, it comes down to purpose (function). What is the purpose of an 'eye'? It is to allow connections. It is a connective interface.
When I tie #1047 (F8 eye knot) or #1010 (R'hand Bowline) - I have want/need to make an attachment of some sort. For climbers/mountaineers, this would be to a carabiner. Irrespective of how large an 'eye' I tie, it still allows me to make a connection (eg to a carabiner or to slip down over a post/bollard).

And of course - the eye is fixed, it is not a noose.

Theoretically, I could manufacture an eye bolt with an eye many diameters in size...it is still an eye bolt (just a very large eye bolt). Same can be said of an eye splice - the 'eye' can be as big as you want - it does not alter the fact that it is an eye splice.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 03, 2016, 05:22:23 AM
I think there is room to debate the term 'sharp',
as the loaded line executes a full 360 degree turn (around 3 diameters)
and ...
Here it should be noted that merely counting the number
of diameters surrounded does NOT solely determine sharpness
--e.g., were those diameters in a row (or, as one can find sometimes,
the initially contacted first two--, the turn would be a 1dia turn (think
of running a line down along a row of trees and turing around the
last in the row).
And, while to some simple degree --a bit above "simplisitic"--,
more diameters are better, rounder, there is also the matter
of shape.  I recall seeing a photo of an Instrom(?) test device's
rope-receiving anchor : it has a diminishing-radius bend for
the line to curve around; one can simulate such curvature
sometimes in a knot.  (And one can remark that such careful
tweaking is matter not of practical concern but only for those
keen to understand knot mechanics!)

Quote
... the Fig 8 where the loaded line executes several partial turns,
 gradually transferring force in the process.
Let me suggest that this knot (by which we mean
the eye knot, usually) benefits from the compression
around the S.Part from the turns of the eye legs,
before the S.Part makes its U-turn around them.



Quote
Indeed, Dan does hold that the 'Key' component of the Bowline is the nipping loop,
However, how he manages to argue that, in a two component knot,
either of the two components is more 'key' than the other, I do not know.
?!  You're confusing "key" with "defining".
Yes, somehow one must stabilize a [please note exact
typing >>>] "turNip"  [<-one capital only!],
but IMO it is the principal engagement of this structure
that characterizes *bowlines*.   And so I include
the Myrtle, and also become aware/bothered by
the fuzzy boundary of the central nipping loop (aka
"turNip"), as it goes from minimal to greater helix
--at some undefinable point one doesn't want to call
it a "loop", but ... .  <sigh>

Quote
the Turnip
Understand my cutesie term's origin : my game
of letter-fusing of adjacent words,
where shared letters are imaginatively run together
and so rise from lowercase in each to uppercase in
the fusion ::
 'turn' ><'nip'
>'turn''nip'<
>>'turNip'<<
("whaTHEck?" you say?!)   ;D

Quote
' When is an Eye not an Eye?  Answer - When it is a loop...'
The eye is a functional aspect of the knot --what
classifies it among other kinds/types/classes of knot.
And the "eye" is indeed adopted because "eye splice"
is universally understood, and "loop" is SOO overloaded
with competing senses --better to stay clear.
("loop" and "bight" compete, e.g..)


Quote
while all Eyes are loops,
NOT if you follow many knot-books' defining "loop"
as a 360-degree turn (a circular thing), which many
do in distinction from "bight".

I respectfully disagree that there are 2 nipping loops in this knot. The second 'loop' which you refer to is not loaded at both ends and so it does not fit the definition of a 'nipping loop'
This is a tricky area, and X. of course wanted such
distinction to make the sheet bend have no loop
but a "hitch".  One might reflect on these similarly
shaped knots and wonder how much of that "ongoing
eye leg" contributes to the ability of the turNip to nip
--something, e.g., one might think is done (variously
well per material & foreces) in the sheet bend
(or in the water bowline which has that clove hitch
crossing part between arguable turNips though it can be
challenged how much action comes via it!

Quote
I would agree with you on this one were it not for the fact that a nipping loop does not have to be externally loaded on both ends in order to function.  For a nipping loop to function, all that is required is for one end to be secured, the round turn frictional amplification is then sufficient to transfer the applied load into the nipped core.
Well, I've echoed, reiterated, concurred in this point.

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 03, 2016, 07:43:52 AM
Quote
Quote

    I would agree with you on this one were it not for the fact that a nipping loop does not have to be externally loaded on both ends in order to function.  For a nipping loop to function, all that is required is for one end to be secured, the round turn frictional amplification is then sufficient to transfer the applied load into the nipped core.

Well, I've echoed, reiterated, concurred in this point.

--dl*
====

I had the distinct impression that Xarax required both ends of the nipping loop (ie a closed helix structure) to be loaded - and this requirement narrows the range of knots that could fit within the definition of a Bowline. Xarax also required a collar structure (which acts as a 'capstan' to a certain extent). Therefore, the presence of a nipping loop and a collar structure is what enables a structure to be classified as a Bowline.

Where this gets murky - in my view - is when we start to examine more complex nipping loops (nipping structures).

For example, the so-called 'Karash loop' has a nipping structure based on a crossing/munter hitch. The question for me is whether the munter hitch component actually functions as a nipping structure. That is, is it loaded at both ends and does it create a compression zone? There is indeed a collar structure... so it is down to the nipping structure.

And then there are the double nipping loops as with #1013 (Double Bowline) - again, both ends are loaded and there is a compression zone. There is also a collar structure. So #1013 is definitely a Bowline.

In my new and revised Bowline Analysis paper - I will be attempting to arrange and classify Bowlines based on their nipping structures..eg;
[ ] single nipping loop based on a closed helix
[ ] double nipping loops based on a closed helix
[ ] crossing/munter hitch
[ ] overlapped double nipping loops (as with #1012)
and so on...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 03, 2016, 01:13:04 PM
I am starting to get quite worried here.

Not only has Constant not waded in on this discussion, but you are all talking about him in the past tense.

What has happened?

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 03, 2016, 03:11:28 PM
He is alive and well...but for reasons unknown to me, he no longer visits the IGKT forum.

Xarax is a passionate man - and he certainly pushed out the IGKT horizon further than most.

His theories on knots and in particular - Bowlines - broke new ground.

You either loved or disliked him - and whichever camp you were in, you would have to admit that he did make significant contributions to our understanding of knots.

...

It would be good to get a summary of his position re the structure and definition of a Bowline... seeking clarification on his theories about the following:

1. The collar structure and the 'capstan effect' created as the collar performs a U turn around the SPart (I recall Xarax adding a pulley substitute for the SPart to illustrate his theory)
2. The 'proper' collar (what exactly did Xarax mean by this?)?
3. The nipping loop loaded at both ends (and not just one end) - a few things come to mind here... this narrows the range of eye knots that could be classified as belonging to the Bowline family (which is better than a wider definition in my opinion). It also makes the definition of a nipping loop stricter. Need verification of Xarax's position on this.
4. The nipping loop and its compression zone contained within the helix. Need further expansion on this.
5. Complex nipping structures such as the 'Karash double eye knot' - per Mike Karash - instead of a simple helix it is now a more complex crossing/munter hitch - does this still fall within the definition of a nipping loop according to Xarax?
6. Tight radius turns and pathways - forcing the working end to wind around single rope diameters/cross-sections - instead of more gentle curvatures - what is his views on this (although this one is not Bowline specific)?
7. Anti-Bowlines - what is Xarax's position on this? - ie Where the collar does not form around the SPart but, instead, forms around the returning eye leg. And according to Xarax - there are 4 anti-Bowline structures (chirality?). And is he in support of the 'anti-Bowline' term?
8. The nipping structure of #1012 (water Bowline) - I see this as 2 nipping loops functioning as a clove hitch (when united) but which can also be spread apart to break the clove hitch structure and instead function as 2 independent nipping loops - symmetry breaking?? And a Bowline based on a 'constrictor hitch' nipping structure - I see this as 2 interlinked nipping loops - but in this case, the nipping loops cannot be separated. I think Xarax and Dan debated these structures at length...but what was the outcome?

I would like some very clear and very concise (ie clarity) on these points.

Edited: Grammar corrections and added further points
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 04, 2016, 07:25:55 AM
Quote
Quote

    I would agree with you on this one were it not for the fact that a nipping loop does not have to be externally loaded on both ends in order to function.  For a nipping loop to function, all that is required is for one end to be secured, the round turn frictional amplification is then sufficient to transfer the applied load into the nipped core.

Well, I've echoed, reiterated, concurred in this point.

--dl*
====

I had the distinct impression that Xarax required both ends of the nipping loop (ie a closed helix structure) to be loaded - and this requirement narrows the range of knots that could fit within the definition of a Bowline. Xarax also required a collar structure (which acts as a 'capstan' to a certain extent). Therefore, the presence of a nipping loop and a collar structure is what enables a structure to be classified as a Bowline.
As noted above, X's position wasn't everyonElse's --did you
miss my remarks about his rejection of the sheet bend
as having a nipping loop (something he I think began mostly
challenging Derek about, ad nauseam)?!  My point to this
comparison was to show --concurring w/Derek's view--
that the apparent "loop" can be effected, can exist,
without its continuation being loaded --it might be a free
tail!  And where it somewhat IS loaded, that loading can
vary by quite some amount, it would seem, enough to
raise the question of making its loading a criterion.
But there is some appeal for that, still ... .
(And one can think that although there might not be
such extended loading of it where it is the crossing
part of a clove-/cow-hitch-like component (e.g. water
bowline
).

I'm reminded that I choose to take a view of what is
a noose based on purely *apparent* structure
irrespective of behavior --which behavior can be so
contingent upon materials & forces : I don't want
knots to be jumping from one class to another based
on a change of materials!  (Now, in more practical
vs. theoretical terms, I would treat "noose" in the
way it's commonly understood, and where just such
particular, sliding-until-tightly-closed behavior occurs.)


Quote
For example, the so-called 'Karash loop' has a nipping structure based on a crossing/munter hitch. The question for me is whether the munter hitch component actually functions as a nipping structure. That is, is it loaded at both ends and does it create a compression zone? There is indeed a collar structure... so it is down to the nipping structure.
Here I disagree (but "feel your pain") : I see that very
crossing-knot structure to have a collar(-ing effect)
--the S.Part bears into the turn around it, after all.
It certainly functions to nip : the knot wouldn't hold
the "proper collar" otherwise!  (Mind, I don't give a hoot
about having this particular propriety, but ... .)


Quote
And then there are the double nipping loops as with #1013 (Double Bowline) - again, both ends are loaded and there is a compression zone. There is also a collar structure. So #1013 is definitely a Bowline.
One can question how much such a coil is related
to the turNip --examining the forces along the strand,
and so on.  But if that isn't part of the group, then woe be
unto us; but we've gone beyond the 360degree turn, now
--as with the mirrored & water bowlines not seeing the
nipping turn's "end" lead (directly) into the eye.

One might consider Ashley's #1016 --which I'm thinking
is one of the many knotting mistakes echoed for ages--,
which concludes with a knot whose apparent turNip
is loaded on one end only, the other held in resistance.
(But consider #1074, at which there is explicit rationale
given for the cryptic advice of the former (and #1882)
--whose images and final knots contradict the advice
(for "double bearing") !!  Methinks Ashely quite sloppy,
in this, alas.)

As for
Quote
you would have to admit that he did make significant contributions to our understanding of knots.
I can agree with "significant" if only measured by volume
(as in "quantity" not "noise").


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 04, 2016, 04:26:40 PM
I have a simple response to the proposed requirement that both ends of the turNip (attention to the capitalisation noted Dan) must be loaded.

Make a Bowline.  Then load only the SP and collar loop leg.

The knot holds perfectly without any loading being applied to the turNip loop leg.

It holds perfectly, because the structure has morphed slightly into a perfect Sheetbend.

For me, this is a simple and perfect example that the Bowline is a Sheetbend with its turNip end connected up to form a loop.

May I presume that we all agree that this has not ceased being a Bowline?

As for what Constant meant, I can only say that there was little of his perspective on the Bowline that I agreed with, but in his absence, all I can do is reiterate my own understanding on the components and functionality of this knot.

NB  For those adventurous souls amongst us that immediately went and tried the Eskimo Bowline, you will have morphed its configuration into a single (or half) Carrick bend / loop knot.  Either way, you will have demonstrated that both ends of the turNip do NOT have to be loaded.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 04, 2016, 07:24:39 PM
You know Dan.

#1016 conforms nicely with my first definition of a Bowline i.e. it has the Sheetbend core (SbC), it has the turNip and a functional colar (well two actually).  It also wonderfully demonstrates the point that the turNip can have an unloaded end and still function perfectly.

(http://igkt.net/sm/index.php?action=dlattach;topic=5593.0;attach=20267;image)

Although Ashley shows the spare loop tidied up, it can just as easily be left floating (as per the middle diagram) and the turNip performs exactly as it does in the Sheetbend - one ended.

But this knot also demonstrates another aspect of knot design - overdoing one advantage and loosing another.

This little knot has four diameters tracing through its nip, so it should be nice and strong...

But, all these cords are sharing the nipping force between them and weakening the grip on the collar end.

Loading just the collar loop leg and the SP in my 'twiddling' polyester braid, and the leg pulls through the nip, around the collar and pulls the end through the nip.

In hairy hemp it might have been usable, but in today's cordage it deserves a skull and crossbones.

Of course, this knot would be virtually useless to Mark as a tie in, because the loop is folded from a bight.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 05, 2016, 03:04:33 AM
Quote
For me, this is a simple and perfect example that the Bowline is a Sheetbend with its turNip end connected up to form a loop.

May I presume that we all agree that this has not ceased being a Bowline?

The Bowline and the Sheet bend are 2 different species. One does not morph into the other merely on account of how it is loaded. Holding the SPart in one hand and the 'returning eye leg' in the other (and then pulling) replicates the functional aspect of a sheet bend - but it does not alter the fact that it is still a Bowline.

If Xarax required both ends of the nipping loop to be loaded - I concur. And not because I am parroting him - but, because it makes sense from a structural point-of-view. It also serves to narrow the definition of which knots could be classified as belonging to the Bowline family. Note there are many on the IGKT forum who dislike the way the definition of a Bowline has progressed - citing that "virtually any eye knot could be classified as a Bowline"... So I am in favour of narrowing the definition, rather than widening it.

Dan indicate that he debated with Xarax at length on the structure of a Sheet Bend....? And that Xarax also disagreed with Derek re the function of Sheet Bend core...? Well, I concur with Xarax that there is no 'nipping loop' component in a Sheet Bend. Oh dear - what I have I done?

I think this comes down to the definition of a nipping loop.

What is the strict definition of a 'nipping loop'?

In my view, for a structure to be regarded as a 'nipping loop', the following criteria must be met:
1. There nipping loop must take the form of a helix or have a helical structure; and
2. Both ends of the nipping loop must be loaded; and
3. There must be a compression zone within the helical structure - so that the compressive force scales according to the load applied at each end (there is actually a mathematical formula here - as load on each end increases, there is a corresponding increase in the compressive force. If only one end is loaded - the compressive force within the helix would not scale at the same rate or magnitude).


Quote
For those adventurous souls amongst us that immediately went and tried the Eskimo Bowline, you will have morphed its configuration into a single (or half) Carrick bend / loop knot

If an 'Anti-Bowline' is tied - simply ring load the eye. This will demonstrate the functional aspect of a Sheet Bend core too - and also show how anti-bowlines are resistant to ring loading. Although there are 4 different forms of the Anti-bowline - depending on which one you tied would orient the 'tails' accordingly. But it is still an anti-bowline -  not a Sheet Bend.


...

In my view, with a Sheet Bend - it is the SPart that crushes its own ongoing tail. As the magnitude of the force increases, the crushing force of the SPart scales accordingly and acts to trap the tail and prevent further slippage. The 'collar' structure provides a framework to stabilise and contain the SPart and its own ongoing tail.

I can feel another debate coming...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 05, 2016, 05:41:32 AM
Quote
For me, this is a simple and perfect example that the Bowline is a Sheetbend with its turNip end connected up to form a loop.

May I presume that we all agree that this has not ceased being a Bowline?

The Bowline and the Sheet bend are 2 different species.
One does not morph into the other merely on account of how it is loaded.
I quite disagree : this comes to the heart of the philosophical,
definitional question What is a *knot*?! --and IMO the
most important thing (at least for theorists) is the geometry
and loading of it.  (And one can point to the vulnerability of
the bowline (per #1010 orientation) to ring-loading just
as a case : the once eyeknot b. is effectively then the end-2-end
knot wrong-way Lapp bend --which can spill!  I would
certainly not say, from a theorist's perspective, that "it's still
a bowline; but, OTOH, from a practical perspective one
is naturally inclined to say "The bowline can spill if it's
ring-loaded --and not the awkward "The b. can become
a <diff. knot which ...>" !)

But, here, in debating/seeking what a nipping loop is, one
shouldn't change loading as though it's of no consequence.

Quote
Note there are many on the IGKT forum who dislike the way the definition of a Bowline has progressed - citing that "virtually any eye knot could be classified as a Bowline"
?!  Let's see how this "anything" has grown?
To my awareness, it's been less open than natural naming
has put it.  But there are tricky cases, to be sure.  I'm just
not getting the feeling that "anything" has been an issue
--just that drawing fine boundaries has been!

Quote
Dan indicate that he debated with Xarax at length on the structure of a Sheet Bend....?
X. seemed to take pleasure in ranting his views,
and favorites were how no one understood that
the sheet bend & bowline were NOT related, and
his all-time favorite that the "so-called, falls Zeppelin
loop" was in no way a Z., ad nauseam!  My reply was
that at least the structure in the first case and the
common way of relating/forming eye-knots from
end-2-end knots in both, DID so relate them
(though the mechanics necessarily changed).
--to which I then pointed to a different way to
relate end-2-end knots & eye knots.


Quote
Well, I concur with Xarax that there is no 'nipping loop' component in a Sheet Bend. Oh dear - what I have I done?
I'm sympathetic to this view --and you can win
at least in the "apparent"ness of it--; but my point
was that the actual amount of contributing, effective
force got by loading difference might be trivial, and
varied over much range.  (If the SPart-side loading
is arrested in the end-2-end knot by the pinch at
the crossing point, one can question how the loading
of the continuation into the eye leg (for the eye knot)
can be so important --that's the rub.)


Quote
I think this comes down to the definition of a nipping loop.
Yes, I take the #1010 as the canonical paradigm.
(But recall that in HMPE cordage this turNip becomes
a rolling circle --a rubbing loop!)

Quote
What is the strict definition of a 'nipping loop'?
3. There must be a compression zone within the helical structure
I'd not use the notion of "helix", since the ideal
is a circle, and practical circumstances keep us from
that --but let's not so much acknowledge the slippery
slope!  We (or I, anyway) do have to face the facts
of that aspect --does a capsizing bowline cease
its prestigious membership in the Bowline Club ...
at what point, exactly ?!  My "anti-bowlines" have
usually a more immediate challenge to resist
helixness.

Quote
there are 4 different forms of the Anti-bowline
You said this before : please enumerate your four.
(I'm thinking of an unbounded set, but maybe I'm too
lazy to see where the fences should go.)

Quote
In my view, with a Sheet Bend - it is the SPart that crushes its own ongoing tail. As the magnitude of the force increases, the crushing force of the SPart scales accordingly and acts to trap the tail and prevent further slippage. The 'collar' structure provides a framework to stabilise and contain the SPart and its own ongoing tail.
Here you show a trouble w/definitions, as I mentioned
above (about when a bowline is/isn't) : whatever is
"ongoing" with this "tail"?!  --those are opposed
concepts (or redundant)!   ::)
The "wrong/opposite-sided" sheet bend tends to draw
up in a more round geometry, more resembling the
bowline's; and the "left-handed" bowline puts
more pinching pressure, I think, where the SPart nips
its tail (at which point it's not very "ongoing" but "herestopping").   ;)

But, as per my thoughts on "noose", I can be swayed
to your side of the debate --what I've been calling
"apparent" so as to avoid trickiness of actual forces.
And I don't think that we've all so much "anything goes"
in this; except that we do show (and can show more)
many knots not considered in the literature.

My locktight loop --a sort of extended Karash structure
(just a single eye)-- is a good knot to consider here for
treatment; it has X.'s "proper collar" (as well as some
slightly different ones), but makes a away-from-eye
wrapping back to the fold-around-SPart & "ongoing"
into eye flow --thereby giving less *collaring* effect
than w/o those wraps.  But ... !?


Again, re #1016, do consider its text and that for #1074:
IMO, that latter is correctly presented --image matches
rationale--, and the former, also with its echo #1882,
is simply lazily, wrongly (incompletely) presented.  It
serves a purpose in our deliberations (and esp. with
the one potential eye drawn snug to the body,
where it will give at least resistance to force
unlike the tail of a sheet bend).
--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knot rigger on January 05, 2016, 12:19:06 PM
ABOK #1016 is close cousin to the "clip two" or "in-line bowline" (ABoK #1074 "bowline with a bight.  Where the working bight and standing loop are formed to be of equal size and form an eye composed of two loops. [1]

I would say that clearly #1016 is not a bowline, but the "clip two" bowline is a bowline.  I make that distinction based primarily on gut reaction (more on that in a moment) but digging deeper the difference between the two is which loop(s) are loaded.  So I would say that one (perhaps obvious) defining feature of a bowline is that the standing loop is loaded.

As far as defining "bowliness".  I agree that a nipping loop, collar, and standing loop (standing as in it's fixed, won't slip like a noose) are three ingredients to a bowline.  However, a knot could possess all ingredients and still not be a bowline.  An example:

Quote
Dan Lehman examined #1033 (Carrick loop) - to see if it would fit the definition of a Bowline.
#1033 has a collar structure and it has a nipping loop that is loaded at both ends. The source of one end is the SPart and the source of the other end is the ongoing eye leg. There is also a collar structure.

This in my view fulfills the definition of a 'Bowline'.

I disagree.  I don't think #1033 is a bowline.

It may be hard to nail down exactly what defines "bowliness" but I know it when I see it.

#1035 is another knot, similar to a bowline, has the three ingredients, but isn't a bowline.  Or the eskimo bowline, not a bowline, but has the ingredients.

So perhaps there is a missing ingredient in the definition, and group discussion may through consensus, eventually (at least for us) define all the necessary ingredients of a bowline... but I would as a healthy dose of the "I know it when I see it" standard as a way of not getting too carried away with:

Quote
... include every loop knot that contains a nipping turn into a giant family of Bowline-esque knots

I agree with Mark that "eye" knot is a useful and descriptive definition.  I also agree that "eye" defines an idea that is independent of scale... a very large circmfrance eye is still and eye IMO.  I agree that "loop" is a term that has some ambiguity (perhaps through sloppy use in knotting literature).  Using #1074 to illustrate the difference between "loop" and "eye", with #1074 you have a two loop knot, but only when the two loops are dressed evenly and loaded together do you have an "eye" structure.

cheers
andy






[1] the photo is from Rick Lipke's Technical Rescue Riggers Guide
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 05, 2016, 12:33:42 PM


 Holding the SPart in one hand and the 'returning eye leg' in the other (and then pulling) replicates the functional aspect of a sheet bend - but it does not alter the fact that it is still a Bowline.

snip....

I can feel another debate coming...

Thank you Mark, we have made considerable progress.

Let us put aside any thoughts of the SbC, it has served its purpose in bringing you to the conclusion that a Bowline loaded only on its SP and its Collar loop leg, leaving the ongoing turNip loop leg unloaded - is still a Bowline.

And there in its simplicity, we have it - the imposed definition that the turNip component must be loaded on both ends in the Bowline, is nothing more than an imagined constraint.  Nothing more than a point which could generate many hours of enjoyable (for some) argument.

It is worth stating it again - The Bowline is still a Bowline even if it's ongoing turNip loop leg is unloaded - if we accept this, then we must accept that the turNip component in the Bowline does NOT have to be loaded on both ends.

The turNip is able to express its compressive force even if one end is only clamped. 

And no, you do not now need to accept every knot which has a turNip component (double end loaded or clamped loaded) into a hypothetically constructed 'Bowline Family', it is a meaningless naming exercise.  Meaningless as me now suggesting that we bin the name Bowline and instead call it the Sheetbend Loop Knot, just as we might join up the ends of a Carrick bend and call it the Carrick Loop Knot...

The only familial action going on in our world of knots is that of shared components and shared utilisation of components.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 05, 2016, 03:14:14 PM

#1035 is another knot, similar to a bowline, has the three ingredients, but isn't a bowline.  Or the eskimo bowline, not a bowline, but has the ingredients.

cheers
andy


Hi Andy,

Your approach is important and whenever we 'feel' that a knot is or isn't a member of a certain group, we should perhaps stand back and ask 'what is driving that intuition?'.

In the case of the two knots you cite, #1035 and the Eskimo, they are both based on the same two components - the Nipping Loop Component (turNip), and variants of the Carrick Component  (the collar being a sub component of the Carrick Component).  So, from a component perspective, these are both Carrick Loops, not Sheetbend Loops.

Perhaps we could start mapping knots into shared component groups?

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knot rigger on January 08, 2016, 02:44:11 AM

It is worth stating it again - The Bowline is still a Bowline even if it's ongoing turNip loop leg is unloaded - if we accept this, then we must accept that the turNip component in the Bowline does NOT have to be loaded on both ends.


If I'm reading this correctly, this assertion means that a sheetbend is a bowline.  I cannot agree.  A sheetbend is different from bowline.  Therefore a nipping turn must be loaded on both ends.

I'm not sure what one would call the helical turn part of a sheetbend though if not a nipping turn.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 08, 2016, 11:28:57 AM

It is worth stating it again - The Bowline is still a Bowline even if it's ongoing turNip loop leg is unloaded - if we accept this, then we must accept that the turNip component in the Bowline does NOT have to be loaded on both ends.


If I'm reading this correctly, this assertion means that a sheetbend is a bowline.  I cannot agree.  A sheetbend is different from bowline.  Therefore a nipping turn must be loaded on both ends.

I'm not sure what one would call the helical turn part of a sheetbend though if not a nipping turn.

Andy, how can a Sheetbend be a Bowline?  The Sheetbend is a bend, but the Bowline is a loop knot.  As you conclude - they are different.  But the difference is not in the core, it comes from how the core is wired up.

And if you insist that a nipping turn must be loaded on both ends, then what has happened to the Bowline that has got snagged up so that all the load is on the returngoing loop leg and nothing on the outgoing loop leg?  Has it stopped being a Bowline just because the nipping loop is no longer loaded on both ends?

However, you are right in part, because the turNip in both these cases is loaded both ends, but the loading on one of the ends is caused by being clamped internally, so load translates around the nip to the inner point of the trapped end, so indeed it is loaded, but only internally.  I think that is likely to be as clear as mud...  Sorry.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 09, 2016, 05:51:09 AM
[I'm greatly annoyed that a prior attempt to reply
 lost text via an unrealized excessive highlighting and
then --poof--, lost to a keystroke w/o awareness until
too late to control-Z recover.  CURSES  >:(  >:(  >:(
]

Holding the SPart in one hand and the 'returning eye leg' in the other (and then pulling) replicates the functional aspect of a sheet bend - but it does not alter the fact that it is still a Bowline.
Thank you Mark, we have made considerable progress.
Let us put aside any thoughts of the SbC, it has served its purpose in bringing you to the conclusion that a Bowline loaded only on its SP and its Collar loop leg, leaving the ongoing turNip loop leg unloaded - is still a Bowline.

And there in its simplicity, we have it - the imposed definition that the turNip component must be loaded on both ends in the Bowline, is nothing more than an imagined constraint.
As I must've previously stressed,
this goes right to the point of what IS a *knot*?!
This is a profound, philosophical/definitional consideration,
not one with an answer waiting to be found outside of
ourselves by empirical examination.

Certainly in some situations, it will make sense to say
the things quoted above --i.e., "still a bowline"--,
where considerations of the vulnerability of that eye knot
to ring-loading or --for the particular loading described--
imbalanced loading that might arise e.g. where a dock
line's eye makes a full/round turn around a pile and upon
the drifting/shifting angle of incidence one leg goes slack
and the other takes all the force.

But it is equally likely that for the purposes of defining *knot*
that one adopts a position in which that entity is described
by an entanglement and loading profile --and change the latter
(as is the case here), you change the *knot*!  And you change
how you have to speak of things, too, which becomes awkward.
One can define an "eye knot" to be an entanglement of two
pieces of material (so, four *ends*) where a one end of piece
A is loaded in opposition to its other end and one end of the
other piece, whose remaining end is unloaded.  (And note that
this allows that the opposing ends to not actually join to form
. . . an . . . "eye" --well, that challenges that class name, huh!   :D
But so far as the "nub" feels, that connection-or-not is irrelevant,
so long as the loading profile obtains.  --by one purpose of defining.
(I've conjured the image of a long tow line tied to starboard cleat
of a barge and then a short compatible line from the port cleat is
tied into the other, forming a . . . bowline --by loading profile,
at least.  (Here, one could argue that the barge essentially completes
the "eye", but ... .)

Here's an exercise, which works better or worse depending on how
frictive your cordage is --surely slipping in HMPE, but holding in most--:
tie the water bowline /mirrored bowline and then pull out a good bit
of the connecting span of the base clove/larkshead structure
--which will result in sheet bend mechanics at those two
(primary & secondary) turNips.  And then muse over whether
you have yet a "bowline" or something other.  Well, my real point
to this exercise was to show that that "ongoing" part --which is the
crossing part in the just-cited knots-- isn't necessarily all so loaded,
or delivering load *into* the turNip (if it can be, as is seen in this
experiment, not be needed for the turNip to hold).  The loading or mere
in-place passive resistance will have some influence on the roundness
of the turNip, though.
But you see how forces and so on are coming here in degrees,
not happily in some black-vs-white clear delineation of things
--that's my assertion.
And why I might lean toward *appearances*, a sort of *nominal*
loading of both turNip ends.

To The Dunnyman, how do you discriminate the U-turning and leg-nipping
part of the fig.8 eyeknot?  Surely, going beyond this area one can
point to its doing this & that.  It is possible by careful positioning
of the "ongoing" end of the nub to also isolate a lose arc of material
to render the S.Part in a sheet-bend-like form, the returning
eye leg making a bowlinesque "proper collar" to keep things intact!
--have we then (only then?) a "turNip"/nipping loop?
Not by "*appearances*".

But this is problematic.

Quote
Meaningless as me now suggesting that we bin the name "Bowline "and instead call it the "Sheetbend Loop Knot", ...
Ha, do realize that in this you have ignored the former end-2-end
knot's asymmetry --that it might be, of it, that the
other side's tail becomes the "ongoing leg" (not very well, agreed)!
Which is sometimes named the "crabber's eye"?

Quote
It is worth stating it again - The Bowline is still a Bowline even if it's ongoing turNip loop leg is unloaded - if we accept this, then we must accept that the turNip component in the Bowline does NOT have to be loaded on both ends.

The turNip is able to express its compressive force even if one end is only clamped. 
Here one must ask : what (then) makes this cited
component "the turNip" ?!
--and my *appearances* can answer that?!

Still, I feel some angst about moving away from at least
some even slight contribution to the "compressive force"
--even one more imagined per appearances than actual!
For, in the Beginning, that was how this structure got
*found* : that the wonderfully simple & efficient bowline
is just the marriage of a bight & loop (aka "nipping loop"...)!

... and then we began the slippery exploration of a slope ...


Quote
And no, you do not now need to accept every knot [that] has a turNip component (double end loaded or clamped loaded) into a hypothetically constructed 'Bowline Family', it is a meaningless naming exercise. 
... just as we might join up the ends of a Carrick bend and call it the "Carrick Loop Knot"...
How did this all of a sudden become "...meaningless..."?!
Just a second ago we were in the rigors of definition,
and then --pooph!-- we engage our checklist but find
the result devoid of meaning?

Here I think we can see something resulting from losing
the *appearance* of the turNip by reference to actual forces
--to material aspects.  (--as one might have to change
classification of a "noose" depending on how well the darned
hitch-to-SPart slides or not along that noose-structure SPart!
.:.  That is a problem I try to avoid, at leas for knot-theory
definitions (but not to a potential rope user who wants a
(working, effective) "noose", no.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 09, 2016, 06:17:38 AM

As far as defining "bowliness".  I agree that a nipping loop, collar, and standing loop (standing as in it's fixed, won't slip like a noose) are three ingredients to a bowline.  However, a knot could possess all ingredients and still not be a bowline.  An example:

Quote
Dan Lehman examined #1033 (Carrick loop) to see if it would fit the definition of a Bowline.
#1033 has a collar structure and it has a nipping loop that is loaded at both ends. The source of one end is the SPart and the source of the other end is the ongoing eye leg. There is also a collar structure.

This in my view fulfills the definition of a 'Bowline'.
I disagree.  I don't think #1033 is a bowline.

It may be hard to nail down exactly what defines "bowliness" but I know it when I see it.

#1035 is another knot, similar to a bowline, has the three ingredients, but isn't a bowline.  Or the eskimo bowline, not a bowline, but has the ingredients.
Of course, I challenge this.  (Some things are hard to see.)   ;)
In some orientation, #1033 is the epitome of *bowline*
--so emphasizing, showing the nipping loop in effect
But one must not draw it up (don't SS369 it!) but leave it
so that the loop stays a loop and not a crossing knot.
Done just so, the knot is perhaps most resistant to jamming?
The sort of collar of the S.Part flows into a collar of the
"ongoing eye leg" and ... no jamming.

So this shows how setting/orientation can have influence;
as it would should your bowline be so loose as to enable
the (partial) capsizing into a near pile-hitch noose.

FYI, I've found/fiddled a <<maybe-it-could-be(called)-a-bowline>>
in which the collar-bight legs are both unloaded (not actively,
just in passive resistance, one), and the eye legs come into
the nub together, one making the turNip and the other
going along until ... .  It's TIB, with sheet-bend workings
if "through loaded".  Anyway, it puts yet a further challenge
to these classifications.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 09, 2016, 07:03:58 AM
Before we go further, we should ask
What is the purpose of this ("bowline') definition?

Because I feel that I'm waging a Right-or-Wrong debate
and that at least implies a basis for making judgements
--but what is it?

One might make "bowline" narrower and then resort
to "bowline-like", or go the other way and need some
means to limit subsets of "bowline" if using a broad
definition, to get back to what the narrow one comprises.

In any case, though, I'm afraid that there will be ways
to muddy the waters --knots & dressings & ... that put
a strain on the delineations.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 10, 2016, 05:05:46 PM
Three new posts from Dan, and one of them is a biggie.

I cleared my desk, loaded my pdf copy of ABoK, pulled three lengths of twiddling cord out in readiness, made a cup of tea, settled my greyhounds so as to be sure of an hour without interruption - and sat down to immerse myself in pure Lehmanese.

Dan, your prose is amazing - efficient, compact and convoluted - just like our knots.

As I read and expand the Lehmanese into Laymanese, while building the forms Dan describes with my twiddling cords, I have to realise that Dan and I are almost at the opposite ends of a knotting perspective.  While I see knots as their elemental components, Dan sees knots as entities, yet at the end of an hour, he has (I think...) convinced me that the Fig 8 is but a pair of interlocking nipping loops (or are they half hitches?).

Dan's perspective is of course, the right one.  While knots are 'bags of components', they are at the same time, dynamic entities, shifting and responding to the forces they are translating.

Then Dan threw a curveball at me - The 'Barge' Bowline -

(I've conjured the image of a long tow line tied to starboard cleat
of a barge and then a short compatible line from the port cleat is
tied into the other, forming a . . . bowline --by loading profile,
at least.  (Here, one could argue that the barge essentially completes
the "eye", but ... .)

--dl*
====

A loaded SP with a loaded lateral hitched into it.

For me, without question, this is the Bowline (it just contains a barge as part of the loop).  Dan has managed to focus the essence away from the outer connections and back into the knot itself with an emphasis on how it manages loads on its various legs.

So what can we take from this?

Our naming conventions seem to have been arrived at by classifying a structure (sometimes even their tying method) with a particular (expected) loading profile.  And this raises a new question - Are we right to continue (and extend) this anachronistic naming system?  Now we are taking one aspect of this system (partial structure) and trying to wed other knots with these partial structures into a single name family.

This leads me to the conclusion that there are two audiences we need to consider.

The first is the Common Usage / Layman group, wedded to the historical names.
The second is the vanishingly small group of people interested in structure and workings of knots, who almost certainly need a new perspective and lexicon in order to clear out the clutter of history.

I belong to the latter group, but I feel this thread belongs to the former, and more importantly, it wishes to remain in it.  Rather than being constructive, contact between the two appears to be antagonistic to both.

I am feeling therefore that it would be better for this thread if I withhold further component focus comments.


Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 10, 2016, 11:32:35 PM
Quote
I am feeling therefore that it would be better for this thread if I withhold further component focus comments.


Derek

Please dont!

This is exactly what we need...

You know that history shows us that it is usually a few determined individuals that go on to make the big breakthroughs...

Often, the people that gave up never knew how close they were to success.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 11, 2016, 11:36:24 AM
Mark,  it is not a case of giving up.  But a constructive thread can be ruined by excessive posting on what are effectively tangential issues.

I will happily continue to contribute from my component perspective for your analysis.  You will have to decide for yourself when enough is enough.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knot rigger on January 11, 2016, 12:06:10 PM
The Bowline is the King of Knots because it is strong, secure, and versatile, as kings should be.  And simple, as kings generally are.

- Brion Toss

This aspect of simplicity is certainly an ingredient in my definition of bowline.

1. A bowline forms a standing eye.
2. A bowline has a nipping turn
3. and a collar
4. and it?s simple to tie, use, and untie

Dan writes:
Quote
Before we go further, we should ask
What is the purpose of this ("bowline') definition?

and Derek writes:
Quote
This leads me to the conclusion that there are two audiences we need to consider.

The first is the Common Usage / Layman group, wedded to the historical names.
The second is the vanishingly small group of people interested in structure and workings of knots, who almost certainly need a new perspective and lexicon in order to clear out the clutter of history.

I belong to the latter group, but I feel this thread belongs to the former, and more importantly, it wishes to remain in it.  Rather than being constructive, contact between the two appears to be antagonistic to both.

Is the purpose of our bowline definition soley for Derek?s second group? Or perhaps is a definition stringent enough to satisfy the latter group useless to the former group?  As a member of both groups, I think there is middle ground, and merit in looking at the question of ?defining bowline? from both perspectives.   They are not antagonistic to each other, or mutually exclusive IMO.

Perhaps it would help to remember that a bowline is simple.  And to some degree, this simplicity is at the heart of it?s usefulness.

btw Derek, I believe ?clearing out the clutter of history? to be a fool?s errand.  By and large, the knots we have today, and the names of those knots are a messy product of messy history.  Live with it :) accept it, it?s not gonna change by decree of the IGKT (or any other way)

I think part of a solution that appeals to me regarding which knot is "bowline" and which isn?t, is the one Dan proposes

Quote
One might make "bowline" narrower and then resort
to "bowline-like",

A definition must have boundaries, it?s inhererant.  To me, to make a definition useful, it must be precise. A definition should provide some clarity, and too broad a definition doesn?t do this.  So my aproach would be to limit ?bowline? in certain meaningful concrete ways, and other knots that are similar but lye outside the delineations would be ?bowline like?

ok then

#1  A bowline is a knot with a fixed eye. 

This seems so obvious as to perhaps not need to be included, but it was pondering the difference between sheetbend and bowline that brought me to include it.  Axiomatically, a sheetbend is not a bowline, therefore the difference between the two should be included as part of the definition.  The fixed eye may be composed of one or two fixed loops. (maybe three)

#2 A bowline has a nipping turn.

I think we can all agree about this, but the devil seems to be in how to define nipping turn.

Mark writes:
Quote
In my view, for a structure to be regarded as a 'nipping loop', the following criteria must be met:
1. There nipping loop must take the form of a helix or have a helical structure; and
2. Both ends of the nipping loop must be loaded; and
3. There must be a compression zone within the helical structure ?

I would further limit (#1) as a nipping turn should have only a helix structure of one or two turns.  More than two turns isn?t simple.  And nipping structures that aren?t loops (helix) are near bowlines, but not bowlines (myrtle bowline, crossing turn nipping structure, etc)

I disagree that a nipping loop must be loaded on both ends.  I see this limitation as primarily a means of excluding the sheetbend from ?bowline?. I don?t think a nipping loop is exclusive to ?bowline? and I think a sheetbend has one.  The primary purpose and defining feature of a nipping loop is the act of compression.

#3 a bowline has a collar.

And I think it only has one collar.  More than one and it?s ?bowline like?

#4 a bowline is SIMPLE

Adding locking tucks to add security to a bowline is clearly part of what bowlines are in the 21st century, with all our slick and stiff modern cordage.  I?m not sure where to dawn the line, but I do think a line should be drawn when it comes to how many added locking tucks are two many for ?bowline?.  Perhaps two.  I would consider a double bowline with a yosimite finish and a lee?s lock a bowline, but to me this knot would be right on the line of what is ?bowline? and what is ?bowline like?  maybe two locking tucks it too many? Maybe it should be only one?  Certainly the resulting knot may not even be obvious that it?s a bowline at first glance.  Not obvious is not SIMPLE.


lastly, in reply to Dan:
Quote
Of course, I challenge this.  (Some things are hard to see.)   
In some orientation, #1033 is the epitome of *bowline*
--so emphasizing, showing the nipping loop in effect
But one must not draw it up (don't SS369 it!) but leave it
so that the loop stays a loop and not a crossing knot.
Done just so, the knot is perhaps most resistant to jamming?
The sort of collar of the S.Part flows into a collar of the
"ongoing eye leg" and ... no jamming.

If I have to dress #1033 ?just so? it fails my SIMPLE criteria of ?bowline?.  I?ve played with this knot, looking for your bowline in there, but must not have your vision.


here is an attempt at a one sentence definition:

A bowline is a simple knot composed of one collar and not more than two nipping turns, which forms an eye composed of one or two fixed loops.


Lastly, Mark, good luck with the paper, looking forward to seeing it.

cheers
andy
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 11, 2016, 06:44:51 PM
lastly, in reply to Dan:
Quote
In some orientation, #1033 is the epitome of *bowline*
--so emphasizing, showing the nipping loop in effect.
But one must not draw it up (don't SS369 it!) but leave it
so that the loop stays a loop and not a crossing knot.
Done just so, the knot is perhaps most resistant to jamming?
The sort of collar of the S.Part flows into a collar of the
"ongoing eye leg" and ... no jamming.

If I have to dress #1033 "just so", it fails my SIMPLE criteria of "bowline".
I've played with this knot, looking for your bowline in there,
but must not have your vision.
?!  You mean that you've been unable to preserve the knot's
loop --central nipping loop-- by relaxed dressing?!  Try better!

As for "just so", touche'.  But there is some of this even for
the common bowline --as my observations around some
trawlers of their 1-2"diameter docklines show (and as I've
shown in photos to this forum) : many knots that surely
originated as bowines have capsized into something not
so identifiable.  One can wonder about how "just so" would've
prevented this.  One can see photos in yachting magazines
where the collar seems (IMO) too loose and yet those knots
remain identifiably bowlines.  But the "just so" point
remains, and irrespective of one's particular "bowline" thoughts,
it points to issues regarding what is **a** "knot" and not
otherwise **anOTHER** knot --just variances in setting,
or in force delivered to same-set knots (those "initially bowlines"
dockline eye knots that became unidentifiable, variously).

Quote
here is an attempt at a one sentence definition:

A bowline is a simple knot composed of
 one collar and
 not more than two nipping turns,
 which forms an eye composed of one or two fixed loops.
So, no triple-eye "bowlines"?
Take a long bight (you don't see ends),
and by your preferred method, using the bight
as a "rope", tie a "bowline" :: this will have
doubled parts throughout because of working with a bight;
it will have 3 eyes, with its "tail" being a bight end.

"simple" seems a gratuitous --and dubious in being judgement--
part of your definition (remove it : what changes? ; replace it
with "complex" : what could that mean?).  I.e., by the rest
of your definition --which is more objective--, you pretty well
prescribe simplicity.
But methinks the mixing of subjective aspects or objective
constraints on size make for odd classifications; in which per
your definition one might wish to include the tugboat bowline
though by some objective criteria it doesn't qualify --but is
so *simple* & quickly tied (and an eye knot).


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 12, 2016, 05:35:17 PM

#3 a bowline has a collar.

cheers
andy

Andy, may I see if I can push you a little on #3

My contention is that #1010 has a Bight Component.  That is, it not only does it have a 180 degree collar, but the legs of that collar extend down and through the turNip.  These legs are critical to the knot in that they stabilise the turNip and allow loop force to be fed up into the collar, allowing a small degree of deflection of the incoming load before hitting the tight turns of the turNip.  Plus of course, one of these bight legs becomes the all important 'End' which is clamped within the turNip and so prevented from simply unravelling.

Ashley would call it the Closed Loop (#32) Component, but the point is that the collar by itself is almost valueless, while the collar plus its two legs are major aspects of this knot.  It is the collar plus the two legs that I call the Bight Component (BC)

Finally, in the spirit of 'Living with it', I am still sticking with Ashley's lovely depiction of a Bowline in #39 where he defines clearly a 'Loop Knot', its purpose, and its distinction from a Hitch.  History is a Bitch - live with it...

#1010 is a Loop Knot, formed from a fully loaded (i.e. one leg to the SP) turNip which in turn grips, and is stabilised by, a Bight Component, the BC in turn is stabilised by its collar bearing around the loaded SP.  The loop is made between the remaining turNip leg and one of the Bight Component legs.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 12, 2016, 07:36:10 PM

btw Derek, I believe ?clearing out the clutter of history? to be a fool?s errand.  By and large, the knots we have today, and the names of those knots are a messy product of messy history.  Live with it :) accept it, it?s not gonna change by decree of the IGKT (or any other way)

cheers
andy

Andy, I agree, 'Clearing out the clutter... is a fools errand'.  I misspoke when I made that statement.  What I should have said was - 'leave history where it is and start from a fresh perspective, unencumbered by history'.  The trouble is, I am finding it a bit hard to envision a compromise between 'ignoring history' and 'selectively ignoring history'.

Dan holds that a 'knot' is the marriage of a loading pattern with a 'tangle', and I agree with him (although I prefer the term 'core' to 'tangle', as core seems to infer a greater level of 'intention).

#1010 has a core comprising just two components.  The characteristics of those two components and the way they are enmeshed to give support, containment and stability to each other, form the basis of a core that has such great utility it has been used and reworked many times over in the world of cord users.

The core formed by the turNip and the BC can be called anything we like - 1st core, White Core, the TB Core, etc.  In the past, I have allowed history to influence me, and I have called it the SbC (Sheetbend Core).  That was probably my first mistake, because it immediately had knotters up in arms the moment I suggested that #1010 was the SbC married to a loop loading configuration.

The SbC (I will continue calling it this until we can agree on a more fitting acronym), despite its simplicity, is amazingly versatile and usable in the vast majority of the possible loading patterns.

The concept that #1010 is the SbC loaded with the Bowline configuration, or that #1431 is the SbC loaded with the Sheetbend configuration, hits a solid wall of rejection the moment it faces the 'historical' perspective.  This stems, I believe, from Ashley's insistence that a knot's use and mode of tying are what defines its classification - see #71 to #73.

So a new question raises its head - does the core define the Bowline or does the Bowline loading pattern define the Bowline?  If it is the latter or both, then we need to define the 'Bowline Loading Pattern' - any takers?

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 12, 2016, 08:47:15 PM
Dan holds that a 'knot' is the marriage of a loading pattern with a 'tangle',
and I agree with him (although I prefer the term 'core' to 'tangle',
as core seems to infer a greater level of 'intention).
But Dan found that his conception had inherent aspects
of orientation/position/even-setting that he'd overlooked,
and it lost its shine to him.  --or it sets some strictures on
what a "tangle" is?

My paradigm was this "sheet bend" structure as discussed,
since the general geometry that can arise from looking only
at the --exploded-- "nub" part (excluding possible "eye" e.g.)
seemed so amenable to being the base for prescribing particular
loadings (of 1-vs-2 "ends" to make the eye knot, bowline
or all-vs-all for the net knot or ...).  But then I realized that
the Lapp bend end-2-end knot really had what corresponded
to the bowine's S.Part pulled down into a quite different angle,
away from the viewer by the usual perspecitve (since the once
"collar", "bight component" now surrounded an free end)!
Moreover, I realize that the marlinespike hitch structure --here,
hitching to the tail-- can suggest further complications of geometry
in a "tangle", and of loading trickiness :: i.e., that it's not so simple
as just prescribing "1 vs 2+A", but might require some ordered
sequence of loading to achieve the desired result.  (In the case
of the above hitch-&-object basis for (capsizing into) a bowline,
it can be dismissed as not really "en-tangled" in the one part
running straight through others (though Derek shows this as
a "component"!?); but make a U-turn with this end and bring
it back into the entanglement and one has the basis, with
careful loading, to obtain a "end-bound bowline" !
Similarly, the carrick bend tangle could take the historically
common form of that lattice, or one of joined crossing knots?!

I've not looked far in testing the "tangle" notion, but it
does seem that I've made unrealized assumptions about
it that need more consideration, but that show problems
with easy application of it.   <darn>

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knot rigger on January 13, 2016, 09:53:57 AM
Quote
?!  You mean that you've been unable to preserve the knot's
loop --central nipping loop-- by relaxed dressing?!  Try better!

perhaps I gave up to soon :)  sorry to disappoint you.  Perhaps I failed in my translation of "Lehmanese into Laymanese" (hilarious Derek! and spot on!).  I did try, honest, but whenever I think I had it sorted (ah ha! Dan is brilliant) I would load the loop of the knot, and what I had would capsize into something that looked neither bowline, or simple.

I grant you that there is a spectrum of ease of setting a knot, from the ease of just pulling on two ends of a basic overhand knot.... to carefully balancing and teasing required form a star knot.  I propose that for the sake of simplicity, a bowline need be nearer the overhand end of the scale rather than the star knot.

your point:
Quote
one can see photos in yachting magazines
where the collar seems (IMO) too loose and yet those knots
remain identifiably bowlines.

Is a very interesting one, addressing the necessity and function of a collar.  I too have observed bowlines with loose collars.  With a loose collar, the structure of a bowline becomes essentially that of ABoK #172, a Bellringer's knot.  Not a secure loop knot, but in can securely be used it as part of a quick release trucker's hitch (name used by grog) a variation of ABoK #2126.  I have used a more secure variation of this trucker's hitch (used to hold up the sidewalls of a big top circus tent).  The nipping turn is doubled in the fashion of an awning hitch (#1854) or a rigger's hitch (#1735) which increases security, but when the load is slacked, the knot is easy shaken loose (this feature being of great use when it came time to dismantle and move the big top)  So back to bowlines: would a double bowline with the second nipping turn "tucked up" like #1854 have any merit?  Anyone know a name?  Awning bowline?

moving on:
Quote
Quote
A bowline is a simple knot composed of
 one collar and
 not more than two nipping turns,
 which forms an eye composed of one or two fixed loops.
So, no triple-eye "bowlines"?

Dan, I'm all for "clip three" bowlines.  Not including them in my stab at definition was accidental, but it does illustrate the problem of "where to draw the line"  If three loops is good, why not 4?  Is a bowline on a coil a "bowline" or "bowline like"?  Now I wonder what merit a "clip three bowline" has over the old standby of #1080, a bowline on a bight?  Perhaps 4 parts of line squeezed by the nipping loops is stronger? 

Quote
"simple" seems a gratuitous --and dubious in being judgement--
part of your definition (remove it : what changes? ; replace it
with "complex" : what could that mean?).  I.e., by the rest
of your definition --which is more objective--, you pretty well
prescribe simplicity.

an excellent point Dan.  Indeed, my slipping in "simple" into my attempted definition was admittedly beating the "simple" point I was trying to make into the ground!

Derek
Quote
Finally, in the spirit of 'Living with it', I am still sticking with Ashley's lovely depiction of a Bowline in #39 where he defines clearly a 'Loop Knot', its purpose, and its distinction from a Hitch.  History is a Bitch - live with it...

a succinct and eloquent rejection of the proposed use of "eye" knot rather the "loop" knot.  I am prone to agree with you.  I see the main argument for "eye" and against "loop" is that "loop" has been made somewhat ambiguous through mis-use, or perhaps over use.  I believe I can embrace both "loop" and "eye".  While they don't mean exactly the same thing, within the context of defining a bowline (or other loop knots) they are nearly synonymous IMO.

Quote
Andy, I agree, 'Clearing out the clutter... is a fools errand'.  I misspoke when I made that statement.  What I should have said was - 'leave history where it is and start from a fresh perspective, unencumbered by history'.  The trouble is, I am finding it a bit hard to envision a compromise between 'ignoring history' and 'selectively ignoring history'.

Can any of us truly be "unencumbered by history"?  My wife tells me I have a talent for "selectively ignoring history"! Perhaps I can help? ;) 

In the context of knotting, and your "fresh perspective" I counsel all of us to base our decisions on utility and merit.  Some nomenclature and ideas in knotting literature and history may be discarded or at least updated, but others are basic foundation material.  (making the distinction is clearly the difficult part!)

Quote
#1010 is a Loop Knot, formed from a fully loaded (i.e. one leg to the SP) turNip which in turn grips, and is stabilised by, a Bight Component, the BC in turn is stabilised by its collar bearing around the loaded SP.  The loop is made between the remaining turNip leg and one of the Bight Component legs.

Your definition is an improvement on mine.  I prefer "nipping loop" to "turNip".  As far as "Bight Component" goes, I was using "collar" to mean the same thing, but I can see that they are slightly different.  I dislike the word "component" as I think it's redundant when used in context (we're talking about the 'components' of knots)  It is troubling to drop "component" from the term, leaving only "bight"... which can be ambiguous.  Specifically, what you're (we're) trying to describe I think is a type of bight, which is squeezed by the nipping loop and also passes around the standing part.  I was working with the notion that "collar" described and defined that idea... but perhaps it doesn't.  Would a bellringer's knot have your "bight component"?  Now that I think about it, perhaps "collar" (as i've heard it used, and use it) doesn't describe "a bight which is squeezed by the nipping loop and also passes around the standing part" perfectly, or specifically enough.  I use "collar" to describe the similar part of a butterfly knot, or a zepplin bend, but those structures don't fit the specific definition as used in "bowline". 

Perhaps "collar" is simply a bight which passes around the standing part, and we add another ingredient to our definition.

#1010 has a (1) collar and (2) nipping loop which (3) squeezes (nips?) the collar legs.

(if there were a crossed eyes emoticon, i would use it here now)

Quote
So a new question raises its head - does the core define the Bowline or does the Bowline loading pattern define the Bowline?  If it is the latter or both, then we need to define the 'Bowline Loading Pattern' - any takers?

I think it must be both, and as far as 'bowline loading pattern' goes : I know it when is see it!  LOL  It seems obvious, which means it probably isn't!  It's a fixed loop.  The SbC (for lack of a better moniker) plus a standing loop = bowline.

I've attached a pic of the "awning bowline" I'm sure a better name already exists, and hopefully someone can enlighten me.

finally, thanks Derek for prompting me to go back and take a fresh look at chapter one of ABoK :)

cheers
andy
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 14, 2016, 02:52:52 PM
This should ignite the BBQ.

[ ] #1152 (Sheepshank)
[ ] #1431 (Sheet bend)

Do these structures have 'nipping loops'?

I maintain my [tenuous] position that a nipping loop must be loaded at both ends - to meet the definition of a nipping loop.

In my view, both nipping loops in the Sheepshank are loaded at each end. This does not make a Sheepshank a Bowline... but, it does mean that the Sheepshank borrows a key 'component' from the Bowline. A Bowline has a fixed eye whilst a Sheepshank has none and also...there is no collar-capstan. So a Sheepshank could never be classified as being a 'Bowline' - because at least 2 fundamental components are missing.

A Sheetbend has a collar-capstan but it does not have a fully functioning 'nipping loop' on account of only one end being loaded. Also, there is no fixed eye. Therefore, a Sheetbend could never be classified as a Bowline because it is missing at least 2 fundamental components. Also, a Sheetbend is configured from 2 separate pieces of rope which are united. A Bowline is configured from a single piece of rope.

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 14, 2016, 07:58:16 PM


 Holding the SPart in one hand and the 'returning eye leg' in the other (and then pulling) replicates the functional aspect of a sheet bend - but it does not alter the fact that it is still a Bowline.

snip....

I can feel another debate coming...

Thank you Mark, we have made considerable progress.

Let us put aside any thoughts of the SbC, it has served its purpose in bringing you to the conclusion that a Bowline loaded only on its SP and its Collar loop leg, leaving the ongoing turNip loop leg unloaded - is still a Bowline.

And there in its simplicity, we have it - the imposed definition that the turNip component must be loaded on both ends in the Bowline, is nothing more than an imagined constraint.  Nothing more than a point which could generate many hours of enjoyable (for some) argument.

It is worth stating it again - The Bowline is still a Bowline even if it's ongoing turNip loop leg is unloaded - if we accept this, then we must accept that the turNip component in the Bowline does NOT have to be loaded on both ends.

The turNip is able to express its compressive force even if one end is only clamped. 

And no, you do not now need to accept every knot which has a turNip component (double end loaded or clamped loaded) into a hypothetically constructed 'Bowline Family', it is a meaningless naming exercise.  Meaningless as me now suggesting that we bin the name Bowline and instead call it the Sheetbend Loop Knot, just as we might join up the ends of a Carrick bend and call it the Carrick Loop Knot...

The only familial action going on in our world of knots is that of shared components and shared utilisation of components.

Mark,

I though that you had accepted that the turNip in the Bowline does not have to be loaded both ends?

Do you now have new evidence that the definition of a nipping loop (turNip) must be loaded at both ends?

If not, then can we move on with the corrected definition?

As for the #1152 and #1431.  Of course, neither of these are not bowlines because neither are loop knots.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 15, 2016, 02:25:39 AM
Quote
I though that you had accepted that the turNip in the Bowline does not have to be loaded both ends?

No - I think you misinterpreted me!

Also, a great once man told me (a long time ago - in a galaxy - far far away):  "If everyone's thinking the same, then somebody isn't thinking!"

Quote
Do you now have new evidence that the definition of a nipping loop (turNip) must be loaded at both ends?

My evidence is in 3 parts:
1. Its my cognitive thought processes - forming a view - with considered evaluation of the core gripping mechanism of a Sheet bend core in comparison to a Sheepshank. These structures I then compared these structure with a Bowline and how that core functions.

2. It narrows (rather than w-i-d-e-n-s) the definition of a 'nipping loop' [yes, this argument is tenuous but still has some merit]

3. In my personal view, a nipping loop is a compression element - and therefore, for it to properly function - it should be loaded at both ends. And this is where I draw the line with the core function of a Sheetbend. There is no fully functional compression element because it is only loaded at one end. However, the Sheetbend does have a 'collar-capstan'.

I need to further study the core functional elements of both the Sheetbend and the Sheepshank so I can fully consider all the facts...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 15, 2016, 08:00:39 AM
I though that you had accepted that the turNip in the Bowline does not have to be loaded both ends?
Is a fig.8 (base, 1st-made structure) a knot with
a turNip --looks much like that of the sheet bend
and then the loop's tail just continues around to make
the rest of the '8',
  . . . exiting out into space . . .
and can return (to complete the eye for an eye knot) into
this 8 in a bight-finish 'a la bowline.
But back to the question, do we have a turNip here?
(And if so, I'd think ... a *bowline* follows!)


Meanwhile, Agent_Smith sees no eye in the sheepshank
while I see TWO --aye-aye!
.:.  Ergo, "double bowline" !
QED


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 15, 2016, 03:10:40 PM
Quote
I though that you had accepted that the turNip in the Bowline does not have to be loaded both ends?

No - I think you misinterpreted me!

Also, a great once man told me (a long time ago - in a galaxy - far far away):  "If everyone's thinking the same, then somebody isn't thinking!"


General Patton's quote  has been discussed, and the argument made that Patton was suggesting that multiple perspectives were important in arriving at a strong conclusion, and this Forum is very much here to air as many perspectives on a topic as possible.  So from that reasoning, I have to agree, seeking different perspectives is important.

However, as some of the Generals other quotes demonstrate, his opinions are sometimes dubious....

"If everybody is thinking alike, then somebody isn't thinking."

"If I do my full duty, the rest will take care of itself."

"In case of doubt, attack."

"It?s the unconquerable soul of man, not the nature of the weapon he uses, that insures victory."

The last one, I rather think that it is the unthinking, uncaring, soullessness of man armed with unbeatable weapons that has led to so much slaughter of humanity...

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 15, 2016, 06:00:41 PM

My evidence is in 3 parts:
1. Its my cognitive thought processes - forming a view - with considered evaluation of the core gripping mechanism of a Sheet bend core in comparison to a Sheepshank. These structures I then compared these structure with a Bowline and how that core functions.

2. It narrows (rather than w-i-d-e-n-s) the definition of a 'nipping loop' [yes, this argument is tenuous but still has some merit]


Mark,  are you confident that 1. and 2. constitute evidence that a nipping loop must be loaded at both ends?

Are you saying that your definition requires the term 'Nipping Loop' to include the requirement for both ends to be loaded, or are you holding that a nipping loop cannot 'nip' if it is only loaded one end (the second end clamped)?

Either way, you are going to need to address the situation of a Bowline with one leg trapped and loaded 100% which can lead to a turNip performing (nipping) correctly while directly loaded only on the SP end.  This is still a Bowline performing under one of the extremes it is expected to handle.

Alternatively, you are going to have to restrict the range of operations the knot can be subjected to in order for it to qualify as a Bowline.  i.e. disqualify the Bowline when it is only loaded on one leg.  Personally, I think this would be a silly distinction resorted to only to justify a distorted definition.

Quote
3. In my personal view, a nipping loop is a compression element - and therefore, for it to properly function - it should be loaded at both ends. And this is where I draw the line with the core function of a Sheetbend. There is no fully functional compression element because it is only loaded at one end. However, the Sheetbend does have a 'collar-capstan'.

Yes, a nipping loop must be opposing loaded both ends, otherwise an unopposed end would simply respond to load on the other end by following it out of the knot.

The key to this issue though seems to be that you do not want to accept that a clamped end is capable of allowing the turNip to 'Nip' i.e. supply compressive force, and you resort to the opinion that it must be clamped both ends "for it to properly function".  So, yet again, when it is not functioning 'properly' as in an end clamped turNip, is this no longer a Bowline?

What I am starting to take from your responses, is a perception that a Bowline made and used 'optimally' has a turNip loaded both ends, but when the Bowline is subjected to non ideal usage, it is still a Bowline because a) that is what it was made as and b) that is what it will revert to when usage returns to 'normal'.

I can accept a degree of mileage from this perspective, in that if sufficiently abused, the Bowline will morph into a noose.  This noose is certainly not a Bowline, and in the transition from clear Bowline to clear noose, there are a continuum of stages when the knot is neither one form, nor the other.

So, my position comes down to either you are forced to define a Bowline under 'idealised' conditions, or you are forced to accept that a Bowline functions perfectly well with one end clamped and so drop the then meaningless constraint of 'both ends actively loaded'.

Finally :-
Quote
There is no fully functional compression element because it is only loaded at one end.
Seriously ??

How 'fully functional' does it have to be?  The Sheetbend has to be one of the most used knots of all time.  It utilises one loaded and one clamped end and is(was) used in the most arduos of environments.  I don't think it would have been used for long if it did not come up to being 'fully functional' do you?

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 15, 2016, 06:59:57 PM

My evidence is in 3 parts:
1. Its my cognitive thought processes - forming a view - with considered evaluation of the core gripping mechanism of a Sheet bend core in comparison to a Sheepshank. These structures I then compared these structure with a Bowline and how that core functions.

2. It narrows (rather than w-i-d-e-n-s) the definition of a 'nipping loop' [yes, this argument is tenuous but still has some merit]


Mark,  are you confident that 1. and 2. constitute evidence that a nipping loop must be loaded at both ends?

Are you saying that your definition requires the term 'Nipping Loop' to include the requirement for both ends to be loaded, or are you holding that a nipping loop cannot 'nip' if it is only loaded one end (the second end clamped)?
In l00king at a somewhat-corresponding sheet bend
--or, using the similar, wrongly derided "left-handed bowline"--,
the opposite-sided version will produce a more *rounded* turNip
(of the end-2-end knot),
which while not changing the base of this argument,
does give an image that swings in Derek's favor.

Quote
Either way, you are going to need to address the situation of a Bowline with one leg trapped and loaded 100% which can lead to a turNip performing (nipping) correctly while directly loaded only on the SP end.  This is still a Bowline performing under one of the extremes it is expected to handle.
Here I quite beg to differ :: How can differently loading
a knot --indeed, going from eye loading to end-2-end
loading (and then there's turNip-only loading, "through
loading")-- at all be reasonably considered, for knot
theory
, dealing with the same knot?!  In practical
circumstances, one will want to consider possible effects
of usage --perhaps the risk of lowering with a large eye
and snagging the up upon something such that the
lowering S.Part lowers to become untensioned while
the eye knot becomes "ring-loaded" and the knot, in
knot theory terms transforms into an end-2-end knot!

But in shaping definitions, I don't accept that knot classes
are immune to such changed loading profiles; indeed, I
posit that *knot* entails a particular profile.

Quote
Alternatively, you are going to have to restrict the range of operations the knot can be subjected to in order for it to qualify as a Bowline.  i.e. disqualify the Bowline when it is only loaded on one leg.  Personally, I think this would be a silly distinction resorted to only to justify a distorted definition.
Yes, that is what I will do, for knot theory.  When I haul
your bowline up through some "V" such that the nub abutts
and jams, I'll be loading that knot qua stopper.  (Should I for
some reason be hauling on the tail, I'd have Ashley's stopper
with one section way loose (the former eye part)!)

So we have, as I've previously remarked, two ways of seeing
"knot", both with good reason to be used, but separable to
different regions of discussion/usage.

Quote
Quote
3. In my personal view, a nipping loop is a compression element - and therefore, for it to properly function - it should be loaded at both ends. And this is where I draw the line with the core function of a Sheetbend. There is no fully functional compression element because it is only loaded at one end. However, the Sheetbend does have a 'collar-capstan'.

Yes, a nipping loop must be opposing loaded both ends, otherwise an unopposed end would simply respond to load on the other end by following it out of the knot.
BEWARE MIXING THEORY & REALITY/materials :
what you describe is precisely what happens when you
load an agreed-by-all-as-it-is-our-paradigm/basis BOWLINE
in HMPE cord --the "ongoing eye leg" feeds through the
turNip and out ... , collapsing the eye to the object
of resistance, and then going from their, ignominiously!!
SO, did our paradigm knot bowline just cease to be that,
during/for THIS loading & material?!
THIS is why I move away from behavior to "appearances",
as in, e.g., calling the venerable two half-hitches & midshipman's
hitch
"nooses" (maybe selecting "noose hitch" for the former)
and not "hitch" & "eye knot" ; I don't want my knot to change
classifications per force or material!

And so while I understand and sympathize with Derek's
point about knot physics per "clamped" ~= "loaded both ends",
I move towards what perhaps underlies Mark's point of view;
in my direct terms, I'll say "in favor of *appearances*" --though
that then leads to perhaps equally problematic deliberations!?

(Recall that I --I think(!)-- advanced my "mirrored bowline"
--i.e., that water-bowline-like-but-with-larkshead-base knot
with "Janus" collaring of the "ongoing eye leg"--
as a case that appeared to have just the sort of nipping turn
(in fact, TWO) Mark insists upon and yet practically more of
the clamped-but-not(much)-loaded such leg, overall --at least
the 2nd/following turNip must take away much force...).
I think that this should be in the *bowline* class, though
it might be pretty shy of Mark's specified loading; it does
though maintain the rounded turNip appearance.)

Quote
I can accept a degree of mileage from this perspective, in that if sufficiently abused, the Bowline will morph into a noose.  This noose is certainly not a Bowline, and in the transition from clear Bowline to clear noose, there are a continuum of stages when the knot is neither one form, nor the other.
Yes, and the ore so with many of the, what-I-call,
"anti-bowlines" --where the returning eye leg enters
the turNip from the opposite side of our paradigm:
there is greater tendency towards the turn becoming
more helical, open/extended than round & compressing.
But even the paradigm knot does this, and can go all
the way to that ("pile hitch..."-)noose structure or be
arrested mid-way, with a decided helix vice turNip.
THIS is not theory, it's observed results.


--dl*
====

ps : Recall my above question re the fig.8 base with
a bowlinesque returning-eye-leg collaring (which preserves
much of appearance...) : was that a turNip in the base
--which resembles the form in the same-side sheet bend
(and which indeed is one of the suggested securing for
that knot --an extension in which the line forms a fig.8
(the U-part/bight left unaltered, though in practice this too
might be given a securing extension, in like-diameter ropes)) ?!
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knot rigger on January 16, 2016, 01:38:45 AM
Whether or not a nipping turn is loaded on one or both ends has no bearing on the definition of bowline IMO

If we define nipping turn as needing to be loaded on both ends, and then define a bowline as having a collar and a nipping turn, then a sheetbend as used as a netting knot, with all four tails loaded, would qualify as a bowline.  Clearly this definition is inadequate and must be modified.

Both Derek and Mark make convincing arguments for nipping loop to be defined as either one leg, or two leg loaded IMO.  I had previously asserted that "nipping loop" need only be loaded only on one leg (but of course loaded on two also counts).  I did so based on the logic that the difference between a sheetbend and bowline is that a bowline has a loop, and that if a sheet bend doesn't have a nipping turn, what does it have?

I think that these three ingredients must be in the definition of bowline
1) has a collar
2) has a nipping turn
3) is a loop knot (for clarity, the #1010 loop form)

if (3) is excluded and a nipping turn is defined as both legs loaded, then a sheet bend as netting knot may be included.  if (3) is excluded and a nipping loop is defined as either one or both legs loaded, then a sheetbend as a bend is included as well.

* Therefore either way a nipping turn is defined (3) must be included in the definition, and if (3) is part of the definition of "bowline" then either definition of nipping turn will describe a (#1010) bowline

In this respect, the distinction of whether or not a nipping turn has both legs loaded has no bearing on the definition of bowline. QED

However.  The sheep shank vs bowline vs sheetbend example Mark had given has merit about what is a nipping loop.  As does Derek's argument that the structure in a sheet bend provides compression (or "nip")  I propose that the non collar structure of a bowline and sheetbend, while similar, and serving similar functions, are subtlety different, and therefore subtlety different names should be applied.

perhaps:

A "nipping turn" is loaded on both ends

and

A "nipping hitch" is loaded on only one end

a sheetbend as a bend has a nipping hitch and a collar

a sheetbend as a netting knot has a nipping loop and a collar

a bowline has a nipping loop, collar, and a loop


for further clarification (ie specificity) the loop of the bowline must connect the a nipping loop leg and a collar leg, and the bight of the collar must pass around the standing part of the knot (to exclude such knots as the Eskimo bowline or Bellringer's knot)

cheers
andy

*added for clarity 1/16/15
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knot rigger on January 16, 2016, 12:59:54 PM
I don't want my knot to change
classifications per force or material!

I emphatically agree with Dan's point here.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 16, 2016, 06:32:51 PM
I don't want my knot to change
classifications per force or material!

I emphatically agree with Dan's point here.

I likewise agree with both Dan and Andy.

But as I learnt as a child - 'I want - don't get'

I want my #1010 to remain a #1010 under all usage loadings and in all possible materials, but this just isn't going to happen.  Extreme ring loading with jerking or cordage with very low CFs and my #1010 will either become something else or will cease to exist.

This brings me to a problem I have with Dan's warning over mixing THEORY with REALITY..

First, we are not dealing with a Theory here, we are attempting to define working descriptions for the purpose of classification.  And as we are dealing with the classification of working knots, those descriptions must be sufficiently robust as to be able to accommodate the reality of a working knot.

A Bowline (for which the default knot is #1010) is a fixed loop knot.
The SP feeds into the knot under a stabilising collar directly into a nipping loop (turNip component) which provides the anchor force for the knot by clamping the exiting WE.
The outgoing leg of the nipping loop forms the outgoing leg of the fixed loop, which returns via the nipping loop to the collar and from the collar, exiting back through the nipping loop to the WE.
The nipping loop is stabilised by the two bight legs of the collar and the collar is partially loaded from one leg of the main loop.
The Bowline is not stable under heavy ring loading when it will morph into a variety of forms eventually ending in a noose.
The Bowline does not exhibit a highly amplified grip on the WE and very low CF cordage may result in force on the return leg of the fixed loop pulling the WE out of the turNip.

This defines a structure, and a loading pattern, and limits the scope of operation beyond which the knot is no longer considered to be a Bowline.

But in making the description, we had to declare 'heavy ring loading'  - this immediately exposes the description to the demand for a definition of 'heavy ring loading' - what deformation has to take place before the Bowline is no longer...?

OR

The Bowline (#1010) is a fixed loop knot comprised of two components, the turNip Component and the Bight Component, configured as the SbC.
SP load is applied to the collared turNip leg.
The fixed loop is applied to the remaining turNip leg and one of the nipped Bight legs.
The remaining Bight leg is left unused.



They both describe the #1010, but neither offer an acceptable level of expansion or enhancement to encompass what I consider to be an as yet, undefined characteristic of a family of Bowlines, i.e. does such a family all have to have the #1010 at their core i.e. #1010 +++  or is there some other elemental Bowlinesque characteristic that screams BOWLINE...?

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 17, 2016, 07:31:04 AM
I want my #1010 to remain a #1010 under all usage loadings ...
And right here you've made a leap that leaves
me turning another direction --I'm not with you.
Loadings matter, and IMO are *definitional*
--and in the realm of "theory",
and, understandably, not so handy to knock about in
parlance of practitioners (though I'll wager that they
can understand the point about such differences, and
that one sometimes engages "ways of speaking" that
aren't meant for profundity or tight consistency).


Quote
First, we are not dealing with a Theory here, [but]
we are attempting to define working descriptions for the purpose of classification.
IMO, definitions such as these should be seen as in
the realm of "theory".  After that, some way of converting
that to common parlance can be sought.

Quote
A Bowline (for which the default knot is #1010) is a fixed loop knot.
"fixed loop" irritates me on two grounds:
1) I favor "eye", as previously advocated, and
2) eye knots are by definition "fixed" --otherwise,
I think what one has should be called a "noose"
which is not a *knot* but a *knotted structure*.

Quote
The Bowline is not stable under heavy ring loading when
it will morph into a variety of forms eventually ending in a noose.
Grammatical point :  "when" can be read as restrictive/qualifying
or non-restrictive (explanatory) --i.e., that it points something
that might or rather is bound to happen; not sure
that a comma clarifies this, either.

But I'm more intrigued by what you think will happen!!  ::)
Care to elaborate --name names-- on these morphed-into forms?!
(Hint : the risk is NO forms!)

Quote
But in making the description, we had to declare 'heavy ring loading'
... and fantasize morphistations !!   ;D
(Did you fix that loop around your neck?)
((I'm having TOO much fun w/this.  ;D ))
(((The pile-hitch noose btw is what results from some
heavy loading of the paradigm bowline --and which is
indicated in that fellow's assertion quoted by Ashley, even
"back in the day" !  And, no, it doesn't always happen.)))

Quote
The Bowline (#1010) is a fixed loop knot compRIsed of
two components, the turNip Component and the Bight Component, configured as the SbC.
SP load is applied to the collared turNip leg.
The fixed loop is applied to the remaining turNip leg and one of the nipped Bight legs.
The remaining Bight leg is left unused.
[I must react to "comprised of", which I say is simply
invalid syntax!  (There are quite good, complementary
uses for comprise, compose, include, ... which should
be fought for, staving off the decline to ... "yaknowhatImean"
grunts dependent fully upon context for sense!  GRRR
]
My sense of what is being said or sought to be said above
is The bowline is an eye knot in which the main load(ed strand)
makes a full turn around --and thus secures-- other parts
of the knot which work to maintain the integrity of this turn.

Perhaps if I leave out specification for what the main strand
(S.Part) does after the "full turn" I allow for the double & water
bowlines
while precluding the fig.8 --a "full turn" being
one that sends the line on in the direction aimed at before
the turn (whereas in the fig.8 it's not full, but a U-turn)!?

But I was waiting to hear how Derek dealt with the fig.8
per his seemingly accommodating view of the turNip vis-a-vis
loading the "ongoing eye leg" or must clamping it.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 17, 2016, 11:33:13 AM

 The bowline is an eye knot in which the main load(ed strand)
makes a full turn around --and thus secures-- other parts
of the knot which work to maintain the integrity of this turn.


--dl*
====

Is that the entirety of your definition for the Bowline Dan?  That is, anything that fits that definition is a Bowline?

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 18, 2016, 06:55:28 AM
Quote
Is that the entirety of your definition for the Bowline Dan?
That is, anything that fits that definition is a Bowline?
Ah, no, it can't be --the conflict of specific vs. general
as highlighted.  I started off just wanting to restate
your words without the "component" terms, and so
was taking a definition of THE ... but then lost train of
thought (or simply wasn't paying close attention!) and
ran off with the idea of a generalization that might serve
to judge *genus* of knots (as was the general thrust of
this thread) --indicated by my remarks following.

So, for "the..." I'd simply describe the collaring bight, yes.
But looking towards "a..." I open things up.  (And seeing
what might thus fall into this generalization, there might
be amendments & expressions of regret or deep sighing.)


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on January 18, 2016, 03:30:33 PM
Well, that really is quite amazing.

(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20262;image)

I have confirmed that the Myrtle C Component at the heart of this Myrtle Loop knot is a 5,1.

Yet only one tiny modification is necessary to destroy this, and render it into the Unknot.

It is not the collar, nor the tuck under the collar.  Just the action of passing the end back into the nip, means that this knot can then be be TIB.

Well done Xarax...  I bow to your observation.

However, have you been able to reverse the reversal, and create the knot 'In Bight' so to speak?

Derek

Hi Derek and hi all,
look at the picture (TIB.jpg) for a TIB method.
If we change the insertion of the eye/bight/loop (?! this is not the thread to use wrong term  :-\ ) in 4th frame as illustrated in the picture TIB_eye_method.jpg we obtain a (new?) TIB knot, look at the following pictures TIB_eye.jpg and TIB_eye_loose.jpg
Ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 18, 2016, 07:39:41 PM
Quote
Is that the entirety of your definition for the Bowline Dan?
That is, anything that fits that definition is a Bowline?
Ah, no, it can't be --the conflict of specific vs. general
as highlighted.  I started off just wanting to restate
your words without the "component" terms, and so
was taking a definition of THE ... but then lost train of
thought (or simply wasn't paying close attention!) and
ran off with the idea of a generalization that might serve
to judge *genus* of knots (as was the general thrust of
this thread) --indicated by my remarks following.

So, for "the..." I'd simply describe the collaring bight, yes.
But looking towards "a..." I open things up.  (And seeing
what might thus fall into this generalization, there might
be amendments & expressions of regret or deep sighing.)


--dl*
====

Dan, can you help me out here.

I am trying hard, honestly I am, but I am struggling to understand this last post.

Could you have another go at rephrasing for me please - sorry for being a thickie.

Thanks.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 18, 2016, 07:44:10 PM
Hi knotsaver,

as a cerebral exercise, that is a great solution.

(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20326;image)

One thing it tells me though is - if I want a midline loop, I would be best to stick with the Alpine Butterfly

Well done tho'

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 19, 2016, 12:39:02 AM
Dan, can you help me out here.
I am trying hard, honestly I am, but I am struggling to understand this last post.
Could you have another go at rephrasing for me please - sorry for being a thickie.
Hmm, okay.
My main point was that there is a contrast in these
"definitions" between having one that is particular
to the bowline vs. one that is more general, that
serves for determining a bowline --for constituting
the "genus bowlinenus" (to sound scientific [no, I'm not Latin]).

And that I'd simply begun my writing in thinking to cast
your definition in sort of straightforward terms (vs. those
of your "component" terminology), and then mid-way
into this I just left off without the specificity of your
definition --which I think might be to just #1010, if
not that and allowing the "left-handed" version (but
SBComponent I think is taken as "same-side" version,
which is specific).
So, I ended up with --as you asked-- a recipe (perhaps)
for constituting the set of bowlineS --#1010 and friends.
Because after specifying the central nipping loop, I allow
whatever else completes the knot so long as it maintains
the integrity of that loop.  And I suggested that my
definition, e.g., allows the water & double bwls., as they
in different ways continue from the nipping loop
--the latter by repetition of turning and the former
in repeating the loop (i.e., making a 2nd one).  And the
Myrtle qualifies in that it maintains the integrity of
the loop, too.

Although we can see cases in which loose dressing and
great forces (maybe elastic material is all the more
deformable and thus problematic, geometry morphing)
challenge "the integrity of the (central nipping) loop"
to various degrees --threatening to become a helix or
worse (capsizing)!  <sigh>


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 20, 2016, 12:32:53 PM
Thank you Dan for your patience.  I now understand, and going back to your previous post, I see that is exactly what you were describing.

To make things slightly easier for me (I have a problem calling anything other than #1010 a Bowline), might I suggest that we drop the term Bowline for the moment, and concentrate on assembling a set of characteristics that includes #1010.  Eventually, you might choose to call this set the Bowline Set, but in getting there it might prove advantageous to forget names and simply look for group characteristics.

There are many ways of listing the characteristics that are required for membership of this set.  One way was from the purely operational direction I offered in the previous descriptions.

A working knot - i.e. it handles load
A fixed loop knot .
Containing the SbCore loaded as per #1010

But as Dan points out, this is too restrictive a description because the set only contains one member - #1010.

In contrast, Dan has offered a more encompassing set (if I might paraphrase) :-

A working fixed loop knot
Containing a stabilised turNip component loaded between the SP and one loop leg.

This set encompasses #1010 together with a significant array of other turNip containing fixed loop knots.  This set might legitimately be called the turNip Loop Knot Set - or, because it contains #1010 you might even be comfortable in calling it the Bowline Set, even though it might contain knots that challenge any sensible association with #1010 and could just a s legitimately be called the Myrtle Set...

I think the point here is, being a member of the turNip Loop Knot Set, is exactly that, and nothing else - it does not mean that a member of the set is a Bowline.  Rather, it is a member of a set that shares some of the characteristics / properties / methods etc. of the Bowline.

Yet others have defined the set as :-

A fixed loop knot with a collar around the SP.

Again, it is a completely legitimate set, and we could call it (amongst many other names) the Bowline Set.

But this leaves me with questions: -
WHY?
What have we gained by describing these sets?
What can we infer or project about members of these sets from the set characteristics?

It seems to me that we are falling into the realm of the kiddies colouring book, seeking pretty patterns - just because they look nice.  We are at risk of pushing working knots into the blasphemy of Decoratives...

Or is there a practical reason for seeking a rational Set that includes #1010?  If such a reason can be identified, it might point more clearly to the characteristics we need to identify in order to define the Set.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 20, 2016, 08:28:00 PM
(I have a problem calling anything other than #1010 a Bowline)
Even Ashley's #1034.5 ("left-handed"/tail-outside bowline) ?!


Quote
But this leaves me with questions: -
WHY?
What have we gained by describing these sets?
What can we infer or project about members of these sets from the set characteristics?
X. would respond that the point (should be obvious; "I must say again...")
is to have knots that don't bind (such as an overhand-based one
might) and don't *linger* upon untying (such as leaving a fig.8
after pulling out the tail part, and then ... SOMEtimes it has
caused careless rockclimbers problems, pulling this end-w/knot
line and getting it stuck --oops/curses).

But I suspect we can find jamming knots that fit the definitions,
and things that aren't quickly tied, and so on.

Quote
Or is there a practical reason for seeking a rational Set that includes #1010?
If such a reason can be identified, it might point more clearly to the characteristics
we need to identify in order to define the Set.
Yes, as just noted : sure grip & quick tying & easy
untying & decent strength ... --are sometimes-#1010
qualities sought in derivatives.  And the left-handed bwl.
and "carrick loop" bwl. #1033 deliver these, both with
more resistance to capsizing, IMO.

But can one write a definition that ensures such qualities
in qualifying knots?  --or doesn't get bogged down in the
reality of materials & forces ... ?!
Probably not, but maybe the effort to form such a group
at least gives a reasonable set of things to offer for those
wanting such qualities, neverminding that the set should
be seen as stocked with much else.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 21, 2016, 10:14:33 PM
oted : sure grip & quick tying & easy
untying & decent strength ... --are sometimes-#1010
qualities sought in derivatives.  And the left-handed bwl.
and "carrick loop" bwl. #1033 deliver these, both with
more resistance to capsizing, IMO.

But can one write a definition that ensures such qualities
in qualifying knots?  --or doesn't get bogged down in the
reality of materials & forces ... ?!
Probably not, but maybe the effort to form such a group
at least gives a reasonable set of things to offer for those
wanting such qualities, neverminding that the set should
be seen as stocked with much else.


--dl*
====

It seems to me that this is starting to go in a circle - picking knots to define the group.  Not particularly useful as a tool to project characteristics, or propose 'missing' combinations.

Also, depending on how you draw #1033 up, its most stable form (drawing up the SP and its opposite corner loop leg) is a Carrick input component, stabilised by a turNip between a loop leg and the WE  (i.e. the SP does not feed the turNip, which is only loaded one side...).  This would fail just about all the proposed characteristics of a member of the Bowline Set.

Shame really, because Fixed loop knots which start with the load entering via a Carrick Component are generally strong, stable, and esy to untie.

Derek

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 22, 2016, 12:30:06 AM
I just went back to the original document and spotted that by the Set descriptors now being used, the three knots on page 10 fail to belong.

The first is the Myrtle, it does not have a loaded collaring bight, instead it has a second turNip (plus, I think the image is of one of the 'false' Myrtles, this one I think has two 'S' twist turNips instead of an 'S' and a 'Z' - can you check pls. Dan.).

The second is the Eskimo, which as soon as it is loaded dresses itself correctly as a Carrick input Component.

And the third, although it has the correct loaded bight collar, the nipping turn has been replaced by a Carrick Component.

One step forward, two steps back...

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 23, 2016, 03:07:25 AM
as noted : sure grip & quick tying & easy
untying & decent strength ... --are sometimes-#1010
qualities sought in derivatives.  And the left-handed bwl.
and "carrick loop" bwl. #1033 deliver these, both with
more resistance to capsizing, IMO.

But can one write a definition that ensures such qualities
in qualifying knots?  --or doesn't get bogged down in the
reality of materials & forces ... ?!
Probably not, but maybe the effort to form such a group
at least gives a reasonable set of things to offer for those
wanting such qualities, neverminding that the set should
be seen as stocked with much else.


--dl*
====

It seems to me that this is starting to go in a circle - picking knots to define the group.  Not particularly useful as a tool to project characteristics, or propose 'missing' combinations.

Also, depending on how you draw #1033 up, its most stable form (drawing up the SP and its opposite corner loop leg) is a Carrick input component, stabilised by a turNip between a loop leg and the WE  (i.e. the SP does not feed the turNip, which is only loaded one side...).  This would fail just about all the proposed characteristics of a member of the Bowline Set.
This just shows some bias of familiarity/unfamiliarity :
the bowline --our seed exemplar, here-- can also be cast
as a "carrick component"'d knot --just SS369 it as you suggest
for #1033.  Yes, loading works against even such hard-set
tying, and the "carrick component" thus realized is reversed
in orientation (S.Part has in one what "ongoing eye leg" has
in the other, of this "carrick component"), but still, it's all there.

(To see this in the bowline, you might try setting by pulling
ongoing eye leg vs. tail --yeah, hardly normal, I know.
But I suggest this because doing the same --same parts,
but more naturally positioned for such opposition--
with #1033 will set things quite nicely for a *bowline*
--which I only just realized in considering this post!
(Hmm, well, one can go too far in this setting; doing it with
some moderation, though, has the effect of drawing down
the (half-)collar around the S.Part, and cannot fold the
ongoing eye leg into the "carrick component" position
--but going too far will do that to the S.Part!)
)

In short, one must realize that the bowline (#1010) has
this quite-UNsnugged "collar" bight, as we call it.  And
that is so ingrained in us that we might be overlooking
the oddity of it, as we elsewhere want to snug things
up into "most stable" forms, and so on.

As for determining the group by some "*seed*" knot,
or working the other direction --of having a group in
mind after collecting desired fruit--, it gets back to one
of the fundamental questions, about the whole point
of such classification; about how one wants "to speak
of ... things", and so on.

I'm at least happy enough to let ideas develop in an
iterative manner of proposition, seeing what follows,
and tailoring refinements based on desire.  In that I
surmise that we are building a sort of *tool* and not
mining Trvth.   :)
But we should already realize at this point that the
vagaries of setting and geometry changes via that
and forces upon various materials makes cataloging
knots by geometrically determined/defined components
a challenge, to say the least.  I've suggested "appearances"
in hopes that some canonical point of assessing these can
lead to some reasonable classification, even admitting that
in practice, significant changes can occur --the "loop" can
be opened into a "helix" or folded into a "carrick comp."
and so on.  I don't think we can do much about that
other than recognize it.


Btw, re snugging up the bowline et al or not ::
I have various small cords tied to my keys ring
(in theory for occasional knot fiddling or use; in practice,
I don't like to mess with these and have other bits of
cordage for use), and the main one --of small binding
cord (hollow braid nylon)-- is joined with a zeppelin
bend
, for decades(!!).  The small (3/16"?) solid-braid
nylon ("hardware store")  cords have had moderately
well-set grapevine bends loosen, and most recently it
was an offset 9-Oh that has now twice/thrice loosened.
So, I thought about how IMO the mirrored bowline
--that "Janus'd" variation with a larkshead base--
although not set tight (not "SS369'd") nevertheless seems
resistant to loosening much, and so I tied a corresponding
twin bowlines bend --one with each tail reeved through
both turNips.  Seems darned loose, yet no looser than tied;
now to see how long it so endures ... .

--dl*
====

ps : no "20-30inches" of snow, YET; but my world is whitened.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 24, 2016, 11:53:50 AM
A chap called Wordsworth once wrote --

"For oft, when on my couch I lie. In vacant or in pensive mood,. They flash upon that inward eye. Which is the bliss of solitude;"

Well, I don't know about the Daffies or the couch bit, but I can certainly accord with that 'flashes upon that inward eye' moment.  Bron has often come crashing through my mental cogitations with - "Derek ! are you twiddling again ? ? ?  Isn't it time you got on with -------- (insert any item from 'The List of Things that Women Think are Men's Duties')".  And yes, I was probably sitting there with a  vacant expression on my face and a favourite length of twiddling cord in my fingers...

And what was I doing?  Yes, you got it, I was Knot Bothering....  I am a Knot Botherer...  and I think, on this Forum, I am in good company.

That was perhaps a tedious preamble to get to the point that fellow KBs will all be totally aware of the fact that we can take virtually any knot, and after a bit of twiddling, transform it into any desired form plus a tangle.  Yes, I can rework a #1010 into a Carrick component plus a tangle.  I can go yet further and work the #1010 into a Noose plus a tangle.  I can take the simplest of completed knots - the OH Knot - and with the minimum of change, I see it is but the Carrick Component with a tucked tail.

But - if I dress and set a #1010 I do not get a Carrick Component, and if I dress and set a #1033 into its most stable form, I get the SP leading straight into a Carrick Component.

Our dilemma, I would suggest, is that as KBs we both know that a totally different knot is only a twist and a flick away...  Yet, although this transform might only be subtle, it means the death of one knot with the creation of another.  As the turNip in #1010 gently elongates, the Fixed Loop Bowline is destroyed and a Noose is born in its place.

You and I know these transforms are so close, so subtle, so hard to ignore, but I would suggest that the knot does not know this...  it only knows what it is and in order to find as simple a means of classification as possible, I would suggest that we have to see the knot 'as it is' and not as 'what it might be'.  We need to turn a blind eye to our knowledge of 'what might be' and adopt the KISS approach.

#1010 as it is intended to be, meets our definition of belonging to the Bowline Set.
#1010 as it might become, does not meet our definition and does not belong to the Bowline Set.
#1033 in its simplest and most stable form does not meet our (present) definition, and so does not belong to the Bowline Set.
Eskimo Bwl. does not meet the (present) loading pattern, and so does not belong to this Set.

Having said that, I have to fully agree that this Set Definition we are constructing, is not some Fundamental Truth, rather, it is simply an agreed set of characteristics which might allow us to draw some common characteristics about its members and perhaps, map in 'missing' members.  But then, as we have not even agreed a purpose for such a Set Definition, we could just a easily ignore the 'working knot' aspect and declare the Set to include any knot that looks remotely Bowlinesque, has ever been called a Bowline, or any of a myriad of subjective aspects.

My personal preference would be to start with a reasonably simple and essentially rational  definition such as the one already outlined based on the SbC and a defined loading pattern, then see what problems it creates and work from there...

PS - what is SS369ing
PPS - I hope you are well stocked with provisions - it looks pretty grim in your 'neck of the woods'.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 26, 2016, 04:34:47 AM
Speaking of Carricks...

Quote
#1010 as it is intended to be, meets our definition of belonging to the Bowline Set.
#1010 as it might become, does not meet our definition and does not belong to the Bowline Set.
#1033 in its simplest and most stable form does not meet our (present) definition, and so does not belong to the Bowline Set.
Eskimo Bwl. does not meet the (present) loading pattern, and so does not belong to this Set.

I'm not sure that I entirely agree.

Clearly, a fundamental property of a Bowline is that it is an 'Eye knot'. If there is no 'eye' - it is automatically ruled-out as a Bowline.

There must also be a nipping structure (ie nipping loop - or you seem to like the term 'turNip' which I should point out was disliked by many on this forum). In my personal view, there are 2 further qualifying requirements:
1) The 'nipping structure' must have a compression zone - and where there is no compression, it is non-functional and therefore ineffective; and
2) The 'nipping structure' must be loaded at both ends.

So for me, the Sheet Bend (#1431 ) does not have a functional 'nipping loop' - as it fails to meet the qualifying elements.

I am also of the view that there must be a 'collar-capstan' structure. Indeed, if this structure is absent - it again automatically disqualifies it from being a Bowline. A further qualifying requirement is that the 'collar' must form around the SPart. If it forms around an eye leg instead of the SPart (eg an 'ongoing eye leg') - this earns it the title of 'Anti-Bowline'. So the badly named 'eskimo' bowline is an 'anti bowline'. So the difference between a Bowline and Anti-Bowline is with respect to where the 'collar-capstan' is formed.

...

An example of a non-functional (ineffective) 'nipping loop' is with the Carrick eye knot (#1439 derived) prior to being transformed.

Compare the transformed image - Carrick Eye knot #1439 derived - does this structure have a functioning (effective) 'nipping loop'?

It has similar form to a munter hitch - and indeed reminds me of the nipping structure in the 'Karash loop / eye knot' in its single eye form.

Another interesting point is that the 'collar-capstan' is not formed around the SPart...it is formed around an eye leg - in this case the 'returning eye leg' - similar to an 'anti-bowline' (aka poorly named 'eskimo bowline'). Although I should point out that in the 'anti-bowline' - the collar forms around the 'ongoing eye leg' and not the 'returning eye leg'.

And of course - does the Karash eye knot have a functioning 'nipping structure' (ie to be functioning and effective - it must have a compression zone)?

Edited: Grammar and text changes to make it clearer...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 27, 2016, 06:40:59 AM
I am also of the view that there must be a 'collar-capstan' structure.
Indeed, if this structure is absent, it again automatically disqualifies it from being a Bowline.
A further qualifying requirement is that the 'collar' must form around the SPart.
If it forms around an eye leg instead of the SPart (eg an 'ongoing eye leg')
--this earns it the title of 'Anti-Bowline'.
So the badly named 'eskimo' bowline is an 'anti bowline'.
So the difference between a Bowline and Anti-Bowline is with
respect to where the 'collar-capstan' is formed.
You might take X's view of having a "proper collar" --something
Derek seems to favor--, but note that I look only for the (infamous?
--"many dislike ..." : really?) "turNip" --"central nipping loop"
and am happy at that.  We can see what each criterion allows and
disallows.

But please note that you abuse my term "anti-bowline" :
it is defined by the side of the nipping loop that the returning
eye leg enters, NOT by what it might (and hold that it need
not) collar.  The Eskimo bowline is an "anti-bowline" because
in brings the returning eye leg in from the opposite side to that
of a bowline --at which point it can only collar the other
eye leg; it could, however, otherwise make a Mytle-like turn
around the nipping loop.


Quote
An example of a non-functional (ineffective) 'nipping loop' is with the Carrick eye knot (#1439 derived) prior to being transformed.
?!  I don't see this as non-functional, but our minds might
be partially so :: one can set the lattice form of the (inchoate)
carrick loop by loading first the (newly envisioned) turNip
so to achieve a *bowline* --what I might struggle to classify
and call a "quasi-anti-bowline", since the turNip really takes
on the *tilt* towards helix typical of them but is held in check
by the rest of the knot, yet the returning eye leg (rudely!)
ignores the turNip in its eagerness to collar the S.Part!
Enter from one side, or enter from the other, OR NOT AT ALL?!
--well, eventually, something gets through the nipping loop
and binds it all together, but not directly.   :o


Quote
Compare the transformed image - Carrick Eye knot #1439 derived - does this structure have a functioning (effective) 'nipping loop'?

It has similar form to a munter hitch - and indeed reminds me of the nipping structure in the 'Karash loop / eye knot' in its single eye form.
I think that we should answer this "no, a nipping loop
doen't collar itself, and is at least "apparently" loaded on
both ends (S.Part & on-going).

Quote
Although I should point out that in the 'anti-bowline' - the collar forms around the 'ongoing eye leg' and not the 'returning eye leg'.
NO, you should not point this out --that's wrong,
as explained above.
"anti-" is used as for "anti-cyclone" : a reversal of
direction in like movement otherwise.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 27, 2016, 01:42:27 PM
Quote
But please note that you abuse my term "anti-bowline"

Perhaps...

But I did not wish to go into myriad of detail - other than the observation that I have yet to see an 'anti Bowline' that has a collar-capstan formed around the SPart! Indeed, I dont think it is possible?

Yes - with the collar-capstan formed around an 'ongoing eye leg' - it is obvious that to perform such a maneuver, one must do everything back-ass-wards (or in an anti direction) relative to a standard #1010 Bowline.

For the so-called 'Myrtle' maneuver this is somewhat different...since I might have surmised that one doesn't need to do everything in the 'anti' direction (relative to #1010).

Quote
"no, a nipping loop
doesn't collar itself

Is that an absolute definition?





Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 28, 2016, 03:45:21 AM
Quote
But please note that you abuse my term "anti-bowline"
But I did not wish to go into myriad of detail , other than the observation
that I have yet to see an 'anti Bowline' that has a collar-capstan formed
around the SPart! Indeed, I dont think it is possible?
You have seen it, for I've shown it somewhere @IGKT// (IIRC).
But look before you type : before decrying/defaming
the Eskimo bwl just extend it as you seem to desire,
and put the darn "proper ('capstan'?) collar" around the S.Part
--the tail is waiting, Janus calls!


Quote
Quote
"no, a nipping loop doesn't collar itself

Is that an absolute definition?
Seems to work, vis-a-vis my notion of *apparent*
loading of the central nipping loop (esp. if "loop" is
assumed/defined to be approx. 360degrees) and
thus excluding tear-drop shapes such as made by
the fig.8.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 28, 2016, 05:30:37 AM
Quote
You have seen it, for I've shown it somewhere @IGKT// (IIRC).
But look before you type : before decrying/defaming
the Eskimo bwl just extend it as you seem to desire,


Yes - of course I am aware of the 'Janus Bowline' (aka double bight Bowline) - but this is not what I had in mind. And I am not decrying/defaming the 'Eskimo' Bowline...i am simply stating that i dont like the name. The knot structure is a different matter - I bare no ill will against it - and i have nothing defamatory to say about it either!

The initial collar-capstan is still formed around the SPart as per the standard #1010 Bowline - is it not?

Its just tail maneuvering which forms another (second) collar-capstan around the 'ongoing eye leg' (and also adds a 3rd rope diameter inside the compression zone of the nipping loop) - there is nothing 'anti' in the initial stages of tying Prohaska's creation. Its all bog standard #1010. Things only go 'south' in the forming of the second collar-capstan. But I guess if you think Prohaska's creation is fully deserving of the 'anti bowline' moniker - I guess thats your prerogative.

By the way - where are you going with all this?

What is your point?

...

Have you had a detailed examination of the photo I provided of the #1439 carrick bend eye knot derived Bowline (in its transformed state)?

Is there a functioning nipping structure?

In its pre-transformed state - I do not find the nipping loop to be functional - it is seized/held in check. Do you see otherwise?

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 29, 2016, 03:25:32 PM
I'm still not sure what value I can bring to this thread.

It seems that Mark is attempting to create a catalogue and analysis of 'Bowlines', but in order to do this, first he must set in place a list of the parameters that define the 'Bowline' Set.

Trying to get a feel for the problem, I believe that the first challenge is to establish a useful 'Scope' to the Set definition.  Set too tightly and the set contains but a single member i.e. #1010 - The bowline.  Yet set too loosely, the set has the potential to encompass the great majority of knotting possibilities and so has no value to Mark in limiting the number of knots he has to include in his analysis.

Of course, it is Mark's paper, and he is at liberty to include any knot he wishes, but it is a technical analysis, and could easily find itself the subject of derision if he included knots which the general knotting world could not countenance as 'Bowlines' unless his Set definition was based on very sound, rational, knot logic.  That is, the Set descriptors can be substantiated and are not subjective.

Doing this against a background of historical name usage, and in a field where the terminology is still in turmoil (nipping loop vs turNip vs hitch, vs loop vs eye vs ring ....), is fraught.  But perhaps if we allow ourselves to be a little less precious over the terminology (a loop = an eye = a ring ...) and if we relegate historical naming convention to the back seat rather than automatically giving it front row priority, then we might be able to help Mark find a Set definition that can help him and at the same time give a reasonable justification for the knots he eventually includes in his analysis.

With this in mind, could I start then with what I consider to be the most obvious parameter - that all 'Bowlines' are Working Knots - that is, they are force machines and it is their nominal dressed working structure that we are classifying.  This automatically eliminates all 'artistically' (i.e. sans active force) manipulated structures, even though these shapes may be utilised in decoratives and knitting circles.

        1. All members of the 'Bowline' Set are working knots whose structures are defined under a nominal loading pattern.

Second, again stating the obvious - all 'Bowlines' are fixed loop (eye, ring, etc.) knots where both legs of the loop are nominally loaded at 50% of the SP load.  That is, both loop legs are nominally equally loaded.

        2. All members of the 'Bowline' Set are fixed loop knots.

Third, as this is a working knot, features of it's creation and destruction can rationally be included.  An important feature of the foundation knot #1010 is that it can be post fix tied, that is, the knot can be tied in its entirety after the end has been passed around or through the anchor point.  Of secondary importance, the foundation knot decomposes completely after the WE has been released.  This has started to move into the subjective, but in my opinion, it is worth including.

        3.  All members of the 'Bowline' Set are post fixing tyable and decompose to nothing after the WE is released to pass through teh anchor point.

Fourth, again sticking with the undisputed - all 'Bowlines' have a loaded helical nipping loop.  But here we need to start being careful to distinguish function from decoration.  In essence, the defining function of the nipping loop is to clamp the WE with sufficient grip such as to allow the 'capstonisation' (if such a word exists) of the applied forces, into the body of the knot , thereby preventing them from drawing the WE out of the knot and destroying it.  To achieve this, I would suggest that it needs to be loaded on one side by the SP in order to be able to drive significant compression force into the nip.  This defining functional characteristic of the 'Bowline' Set also declares the primary weaknesses of this set, namely, loss of nip leads to loss of knot integrity, and concentration of load into such a short length of cordage seriously compromises knot strength over other, stronger, knots.

        4.  All members of the 'Bowline' Set have a fully loaded (i.e. SP load vs loop load) helical nipping loop, whose function is to provide end locking of the WE, (and following from this, the WE must leave the knot via the nipping loop)

Fifth, the helical nipping loop is notoriously unstable and must be prevented from morphing into an open helix.  In the #1010 of course, the helix is stabilised by a bight held taught by the opposing forces of the loop and the SP.  This effect is achieved by a long bight collaring the SP and extending through the nipping helix and into the main loop.  Other means of stabilising the nipping helix are possible though, and here we step firmly into subjective territory.  I can find no rational argument to support expanding the set by including all other possible means of stabilisation or even including specific alternatives such as a second nipping helix as in the example of the Myrtle Loop knot.  So, I will set this one as bight stabilised at the moment and leave it open for someone to come up with a logical argument for including different methods of helix stabilisation.

        5.  All members of the 'Bowline' Set have the nipping helix stabilised against opening by a long bight retained tensioned by loading between the loop and its collar around the SP.

I think that those five definitions are all logically sustainable and of course, they define a Set which includes #1010.  The question is, is it wide enough to encompass the set of knots that Mark would LIKE to call Bowlines?



Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: KC on January 30, 2016, 01:03:35 AM
Can't remember where/when; but i first learned of the 'eskimo' as a 'jacked-bowline'.
.
As most lacing structures the eye of the Bowline is meant to pull along it's length,
and then too along the ropes length/not 'splayed'.
.
eskimo/jacked thingy professedly would have it's locking mechanism turned, so then be more apt to then be able to have pulls across eye/perpendicular to line. 
This for me came to be in use for
loading a pulley with (red)line loaded in it
-from the ground to lay over the target branch it will hang on
-with the eskimo /jacked (blue line)as the eye of a bowline holding the pulley placed on the pulley system top and around it's lowers
-then inverting the deal on a branch overhead;
-to leave the bowline choked like a sling, with the (blue)length of the line for removal to the ground
-holding the pulley/(red)rope for rigging.
.
this can take a lot of line especially for an 80' height, loading in not just single redirect/1st class lever pulley system,
but advancing to  2 or 3/1 systems etc.
because the systems and holding line already take a lot of line;
but then would need 2x that much to have the pulley system lay across target support, both ends on the ground!
.
using the blue/bowline line as sling would put a spread apart force on the bowline eye/not pulling down the length.
So 'jacked' position by 90degrees would then lock when the pulls themselves where 90 degrees different
(being horizontal rather than vertical)
.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 30, 2016, 02:14:27 AM
Quote
using the blue/bowline line as sling would put a spread apart force on the bowline eye/not pulling down the length.
So 'jacked' position by 90degrees would then lock when the pulls themselves where 90 degrees different
(being horizontal rather than vertical)

Yes, this has been pointed out before by others.

You are describing 'ring-loading' - this particular 'anti-Bowline' (aka poorly named Eskimo Bowline) structure - when ring loaded - mimics the function of a Sheet Bend. It is resistant to the effects of ring loading .
   In contrast, #1010 standard Bowline is vulnerable to the effects of ring loading.

The same can be said of #1034 1/2 (L/hand Bowline) - it too is resistant to the effects of ring loading - although not as effective as the 'anti-bowline' because there is no collar-capstan. The presence of the collar-capstan in the 'anti-bowline' in its ring-loaded configuration boosts its performance.

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 30, 2016, 02:53:28 AM
Quote
Trying to get a feel for the problem, I believe that the first challenge is to establish a useful 'Scope' to the Set definition.  Set too tightly and the set contains but a single member i.e. #1010 - The bowline.  Yet set too loosely, the set has the potential to encompass the great majority of knotting possibilities and so has no value to Mark in limiting the number of knots he has to include in his analysis.

The reference to 'loose' and 'tight ' - I have previously preferred 'narrow' versus 'wide' - per legal construction used by Judges in a court of law. Creating too wide a definition of certain issues in legal proceedings is problematic.

I would prefer if you avoid suggesting that this is my issue or my project alone. I have seen this matter as a problem waiting for a solution for a long time now....and I can actually see a tiny little light appearing down the end of a very long tunnel.

Quote
Of course, it is Mark's paper, and he is at liberty to include any knot he wishes, but it is a technical analysis, and could easily find itself the subject of derision if he included knots which the general knotting world could not countenance as 'Bowlines' unless his Set definition was based on very sound, rational, knot logic.

Yes, it is 'my' paper - but I usually see myself as 'editor' first and author second. I am relying on input and advice from several sources - chiefly from amongst the IGKT.

I have a vision that it will be important to showcase certain knot structures to illustrate the core function of a Bowline.
For example, I am of the view that the following knot structures must be compared and contrasted against the #1010 standard form:
[ ] #1431 Sheet bend
[ ] #1033 Carrick loop
[ ] #1152 Sheepshank
[ ] anti-Bowline (with collar-capstan formed around ongoing eye leg)
[ ] karash loop (single eye knot version)

I will be exploring the core function of a Sheet Bend - and closely comparing it to the core function of a standard #1010 bowline.

I will also be exploring various 'nipping structures' - which stray from the #1010 standard helix form.

Quote
I would suggest that it needs to be loaded on one side by the SP in order to be able to drive significant compression force into the nip
I was reading very carefully to learn what your position is with respect to how the single helix 'nipping loop' is loaded (ie SPart side alone or both ends loaded).

I of course am compelled to ask the million dollar question..."Is there a Bowline in existance that has a nipping loop that is only loaded at one end - ie the SPart end loaded (not both ends loaded)?

If there is, where and what is it? I would like to see a detailed photo please.

//////////////////////////////////////

Other than that, I am in general agreeance with your 5 points...except for the remark that the ..."The WE must leave [exit] the knot from the nipping loop". It could of course also exit/deviate via the collar-capstan in parallel to the SPart.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 30, 2016, 06:49:38 AM
Quote
You have seen it, for I've shown it somewhere @IGKT// (IIRC).
But look before you type : before decrying/defaming
the Eskimo bwl just extend it as you seem to desire,

Yes - of course I am aware of the 'Janus Bowline' (aka double bight Bowline) - but this is not what I had in mind. And I am not decrying/defaming the 'Eskimo' Bowline...i am simply stating that i dont like the name. The knot structure is a different matter - I bare no ill will against it - and i have nothing defamatory to say about it either!

The initial collar-capstan is still formed around the SPart as per the standard #1010 Bowline - is it not?
...
Read carefully, please.
"IT" is NOT --and that was the point.
You can take what you replied, and then cut the
returning eye leg and fuse it to the tail, that will
get you what I remarked at --and the anti- certification!
(In fact, that was how I came upon some very interesting
*bowlines*, if not this one itself, which sometimes I think
I prefer to the non-anti one, but I'm not sure why.  By
looking at a diagram and re-connecting parts to different
parts --something that can happen accidentally, too!
(We proudly call that serendipity, unless no one is looking,
and we claim ingenuity later.  ;)  ))


Quote
Have you had a detailed examination of the photo I provided of the #1439 carrick bend eye knot derived Bowline (in its transformed state)?
Is there a functioning nipping structure?

In its pre-transformed state - I do not find the nipping loop to be functional - it is seized/held in check. Do you see otherwise?
You remarked at my criterion ("360deg") for qualifying
a nipping loop and that went with rejecting it of the
crossing-knot form, where I find it collaring itself.

And from the lattice form of your 2nd-of-four images,
I can load the S.Part & on-going eye leg so as to lock
in that apparent nipping loop and satisfy my desire for
a *bowline* --just as done w/#1033 (which thus formed
is IMO a knot worthy of much better awareness & usage!).
(But a dislike : the nipped part of this surprise bowlinesque
eye knot makes the S.Part turn around 1dia, effectively,
as the would-be 2nd actual strand nipped aligns with
the axis of tension.  This can be altered in some ways.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 30, 2016, 07:25:18 AM
An important feature of the foundation knot #1010 is that it can be post fix tied,
that is, the knot can be tied in its entirety after the end has been passed around
or through the anchor point.  Of secondary importance, the foundation knot
decomposes completely after the WE has been released.  This has started to move
into the subjective, but in my opinion, it is worth including.
//
 Fifth ... Other means of stabilising the nipping helix are possible though,
and here we step firmly into subjective territory.  I can find no rational
argument to support expanding the set by including all other possible
means of stabilisation ...

One could look upon the significant aspect of your Point 3 as defining,
and see what it garners as a set.  So, I don't understand why you
"find no rational argument ..." for this, and instead want to limit
the set by further criteria?  --to what point?  There might be some,
but I hope that people can see a point to defining this broader set
--whether called "bowlines" or something else, which would be
said to include *bowlines*--, as it has such a character to it.

As for "helical loop", I feel Occam wanting to slice away a seemingly
gratuitous adjective : do you have other "loops" in knotting?
I can conceive of doing clever things with hollow-braid (loose)
cordage by tucking through the braid, but, in general, one
would rather oppose "loop" and "helix" --neverminding the fact
that the former is an extreme(ly tight) case of the latter.

(Indeed, one might think of "anti-helix" where the turn comes
back vs going away, so that the "crossing point" feels pressure
of its adjacent strands --making this canonical, as practical forces
will often see the "loop" open, lose such contact.  Canonically,
though --and I'm thinking this applies to my "*apparent*"--,
that would be a separator perhaps of "anti-bwls"!?)

As for #1033, let's look at this more intelligently than forcing
into a lousy form.  (Egadz, Ashley's drawing of the supposed
set knot is rubbish!)  As an eye knot for resisting capsizing
and for being easy to untie, it's quite good, in a form not
hauled tight --just as one doesn't haul #1010 tight.   I'd
like to see this tested!


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knot rigger on January 31, 2016, 02:15:25 AM
Is this knot a bowline? or not?  If it is, why is it? If it's not, why not?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alpineer on January 31, 2016, 10:30:25 AM
It's the standard #1010 Bowline secured with a Half-Hitch on the returning Eye Leg, tail then passed through the collar, followed by a second HH on the S.Part, finishing with the tail passing (pointlessly?) back through the Eye.
So yes, it's a Bowline... with additional tail maneouvers to enhance security. 
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on January 31, 2016, 02:02:43 PM
To any interested IGKT members...

I have uploaded VER 2.2 of the Bowlines Analysis paper (31 Jan 2016).

Its a PDF file and its unlocked - not password protected.

Go here to download it: http://www.paci.com.au/knots.php


I welcome constructive criticism.

If you want your name deleted from the paper - please let me know and I will do so.

There are undoubtedly going to be typos and other technical errors. Its a work-in-progress. So abusive remarks and/or comments of a defamatory nature would be unwarranted and unwelcome.

I have acted in good faith at all times...I just want to get this technically correct/accurate. I also would like to acknowledge those persons who have posited / theorized / shared their knowledge. Xarax is absent - so I had to take some educated guesses at his theory re the 'proper collar'.

I look forward to improving the paper with your considered feedback.

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 31, 2016, 06:09:15 PM
Mark,

Well done on producing such a professional document.

I have a couple of points I would like to discuss, but first up, a safety issue, the Myrtle you show on P18 is not a Myrtle, I think Dan has called it a 'False Myrtle'.. it is made from two Z nipping loops which are subject to positive cogging.

The Myrtle MUST be made from one S helix and one Z helix, it is the only safe form.  Two Z or two S are both positive cogging.

I believe in the example you give of coiled springs, the S form is what you have called 'Left Hand' and the Z form you have called 'Right Hand'.  Is there a rationale for calling them 'Left' and 'Right'?

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 31, 2016, 07:25:26 PM
OK, responding to version 2.2.   I see a significant reference to the 'Capstan Collar'.  Reading back, I see this seems to have been sold to you by Xarax.

While Constant was technically correct in holding that the turn of the bight around a static object (the SPart in the case of the Bowline) can exhibit the Capstan effect, in reality, in the Bowline, this does not exist.

If you take a turn around a static object (a capstan), and load both ends equally, there is essentially(except - see Note 1) no capstan effect.  The capstan effect comes into play when the ends are differentially loaded, then the coefficient of friction and the 'amount of turn' come into play in shedding a proportion of the differential force into the static capstan.

You might be tempted to argue that indeed, one leg is loaded with 50% (from the loop), while the other is the WE and so is zero loaded.  However, the reality of the situation (in normal CF cordage) is that the nipping helix (containing a nominal two cord diameters) holds essentially all of the returning force from the loop leg, so in reality, the collar sees only a tiny fraction of the loop load and so there is no differential loading for the capstan effect to come into operation.

In fact you demonstrate this nicely on page 20 where you show that the loop force was unable to penetrate the nip in order to tighten up the collar, and you make the point that "Even at 1 metric ton, the collar can still be manipulated".  This would not have been the case if any significant amount of force had escaped the nip and brought to bear a capstan effect around the SPart.

I am sorry, but in the case of #1010 the assertion of a working 'Capstan Collar' is a seriously misplaced application of cordage science, and using the term 'Capstan Collar' is likely to provoke disagreement with use of the term or the functionality it implies.

Derek

[Note 1.  Where a bight collar exists around a static object (capstan) and both ends of the cord are loaded equally, the capstan effect comes into play in that the loading is shed progressively into the static object, such that the loading in the cord at the mid point of the bight collar is slightly lower than the applied load.  If the cord takes multiple turns around the static object, the the centre turn will be significantly lighter loaded than the applied loads.]
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 31, 2016, 08:23:35 PM
The 'Bight Component'

First up, a bight has it two legs laying adjacent. If they are crossed, you are heading towards a new (nipping) loop.  So in some of the examples you give when the collar legs enter another object from different sides, this is no longer a bight.  [NB Bight legs are significantly Negative Cogging.  If the legs are arranged to approach from opposite directions, they become Positive Cogging.  The difference is significant.]

Dan recently took me to task over redundancy in using the term 'Nipping Helix', when any turn has to be a helix.  But I had used the term deliberately in order to stress the fact that this object is a helix, that is, it is not symmetrically loaded, and under load it creates a lateral force which attempts to 'open' the helix.  Any knot that uses this 'Nipping Helix' component, needs to compensate this tendency, and in the case of the Bowline this is accomplished by the loaded Bight Component.

If I may reproduce, with your permission, part of your image of the #1010 on page 6, in order to demonstrate my point :-

(http://igkt.net/sm/index.php?action=dlattach;topic=5593.0;attach=20417;image)

The Bight Component, is essentially strung out, loaded loop leg one side and collared SPart the other side.  This tensioned Bight acts to resist the turning moment of the loaded Nipping Helix.  In fact it is the Bight legs, trapped by the Nipping Helix that deliver the counter turning moment.  As mentioned in the previous post relating to the 'Capstan Collar', very little force escapes the Nip and so the Collar only plays a minor role in stabilising the Nip, but of course, it does play a part in maintaining the Bight component at times when the loading is trivial.

Remember also, that Bight legs are negative cogging, so in the nip, force is transferred from the loop leg into the WE and both Bight legs contribute to supplying the necessary moment to stabilise the Nipping Helix.

My point is that it is the whole of the Bight, not just the collar that provides the all important 'Nipping Helix' stabilisation force.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on January 31, 2016, 09:45:33 PM
Finally, and then I will shut up.

On page 15 you use a decorative Carrick mat to demonstrate that #1033 is a Bowline.

Although you start this document talking about using the Bowline in a working environment, your list of defining characteristics does not mention that these forms are not decorative constructions, but are working, loaded, force machines.  Perhaps you omitted this because this is self evidently your intention to discuss working knots.

Why then have you used the decorative form of #1033 to argue that it fits the definition when, in use, it takes up the form of an entry Carrick component stabilised by a turNip??

An page 13 then we have #1033, a Carrick based knot - the Karash, a Bight stabilised Carrick - #1439, a Carrick stabilised Carrick, and the Lee Zep - which is a Myrtle with the WE wrapped and tucked (at least it is a legitimate Myrtle, with one S and one Z).

Of note, on page 17, you mention that the Karash double loop - "remains easy to untie even after heavy loading" - doubtless this is courtesy of its central Carrick component - renown for its strength and resistance to jamming.  Just a shame it is not PET.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knot rigger on February 01, 2016, 03:15:25 AM
Agent_Smith:  Congratulations on the latest edit of your impressive bowline paper.

One small note, your paper expresses uncertainty regarding the origin of the Yosemite Bowline, see this relevant link:

http://igkt.net/sm/index.php?topic=5357.msg35736#msg35736 (http://igkt.net/sm/index.php?topic=5357.msg35736#msg35736)

Certainly a small point of improvement :)

Regarding my previous post #340 and alpineer's reply:
Quote
It's the standard #1010 Bowline secured with a Half-Hitch on the returning Eye Leg, tail then passed through the collar, followed by a second HH on the S.Part, finishing with the tail passing (pointlessly?) back through the Eye.
So yes, it's a Bowline... with additional tail maneouvers to enhance security.

I dub this knot the "if-you-can't-tye-a-knot-tye-a-lot Bowline"  and I posted it to raise the point of efficiency in tying.  A characteristic of what has made the bowline the "king" of knots, is it's general utility, a part of which is the feature that it's easy to tie and untie.  And therefore it's easy to remember, and correspondingly hard(er) to mistakenly tie erroneously.  Adding an extra tuck or turn to improve the security of the classic #1010 is certainly not a new idea (see ABoK #1015) and slightly complicating the tying method for an improvement in security has merit, but...

what amount of piling on tucks and turns impedes the utility of the bowline to such an extent as to outweigh any gain in security?

my two cents :)

again, Mark, great job on the paper

cheers
andy
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knot rigger on February 01, 2016, 03:28:55 AM
...
I am sorry, but in the case of #1010 the assertion of a working 'Capstan Collar' is a seriously misplaced application of cordage science, and using the term 'Capstan Collar' is likely to provoke disagreement with use of the term or the functionality it implies.
...

Derek, an excellent logical criticism of the (mis)use of "capstan" as it applies to the collar structure of a bowline.

Quote
I believe in the example you give of coiled springs, the S form is what you have called 'Left Hand' and the Z form you have called 'Right Hand'.  Is there a rationale for calling them 'Left' and 'Right'?

I believe the rational comes from the lays of stranded rope.

http://www.animatedknots.com/images/ropelay.jpg (http://www.animatedknots.com/images/ropelay.jpg)

cheers
andy
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 01, 2016, 04:42:32 AM
Dan recently took me to task over redundancy in using the term 'Nipping Helix',
when any turn has to be a helix.  But I had used the term deliberately
in order to stress the fact that this object is a helix, that is, it is not symmetrically loaded,
and under load it creates a lateral force which attempts to 'open' the helix.
Any knot that uses this 'Nipping Helix' component, needs to compensate this tendency,
and in the case of the Bowline this is accomplished by the loaded Bight Component.
Except consider the sheepshank which bears striking resemblance
to the bowline except that its corresponding-to-"collar" bight
surrounds nothing and thus gets support from nothing (but
the firmness of the cordage).

Moreover, consider that many bowlines at least when set
with a not-loose if not snugged collar will not be doing
much immediate opening toward a helix as doing
the sort of compressing of the nipped parts that Agent_Smith
views as a defining characteristic of a "nipping turn".
(Or consider bringing a line to a rail with a series of
such nipping turns (an extended clove hitch, so to speak).
With the rigid surrounded object, one doesn't have
helical aspects, right?  --or with softer stuff, so long
as the proper *tilt* of that turNip is maintained
--but that is a maintaing (IMO) the precedes taking force
against the helical opening.  (Or is this too much play at
the specific angles & forces?  --yes, whatever goes on
will if not checked lead to ... helical opening.)


--dl*
====

ps : Yes, I too was bothered by the "capstan...." wording,
which was putting a lot of focus on something not so worthy.
(I suppose in slicker stuff there can be the draw & turning
of collar part around the S.Part, with some slippage at the
entry into the nipping turn and so needing the turn and
further nip of the tail!?  I'd offered the sheepshank as some
counterpoint to this assertion, as well.)
Which concurs in your point ...
Quote
... relating to the 'Capstan Collar', very little force escapes the Nip
and so the Collar only plays a minor role in stabilising the Nip,
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 01, 2016, 06:40:53 AM
Thank you for the feedback guys...I am working right now to make corrections and will upload the next version later today or tonight (Australian East cost time).

I agree that the 'capstan effect' is overstated...but, i have to juggle different viewpoints. I am in direct contact with Constant Xarax and am presently digesting his comprehensive email to me.

i am trying to find some ground 'half-way' (or middle ground) here.... having reviewed some early feedback and also going back to the drawing board... the 'capstan effect' plays a role during initial stages of loading but, the compressive power of the nipping loop takes over and dominates.

So the middle ground here is that there is a 'capstan effect' - but, it is not a significant factor at higher loading where the compressive power of the nipping loop is the dominant force.

I have some more photos of a Sheepshank which will be included in the mix...

I would like to quote directly from Dan Lehman and Derek Smith - directly publishing their position statements in the paper (and of course - to bring balance to the force - I must also include Xarax).

Thanks,

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 01, 2016, 09:40:45 AM
VER 2.3 is uploaded for comment.

Please remember that this is a work in progress.

Added page on Sheepshank.

Changed page on Sheetbend.

Added another eye knot - total of 5 knots to examine and contrast to test Bowline theories.

A few other typos and corrections made.

Downplayed role of capstan effect (hopefully I have found the 'middle-ground' here)... Clarified that it plays a role during initial stages of loading before compressive action of nipping loop becomes the dominant force.

Am still to add quotes from key IGKT members...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 01, 2016, 12:36:18 PM
Wow Mark, I am impressed, that is quite some significant rewrite (restructure) -- for an encore you require two Oil Rig anchor hawsers and a length of Space Elevator ribbon... 

I am starting to feel a little bit 'picky' now, but on a principle issue, I feel it is probably valuable.  The issue is this 'Capstan Collar' which you have now relegated to 'inhibits tail slippage during initial stages of loading', which I must presume is distinct from the initial stages of dressing and setting.

It is very hard discussing this 'through a proxy'.  Would Constant be in agreement with your posting the salient parts of his email conversation here, so we can at least see his rationale?

To demonstrate the issue of principle I have with according the collar any capstan effect, can best be explained by using the example of a simple lever.  If we set up a lever fulcrum system to give us a 2:1 advantage, then it does not matter how large of small a force we apply to the handle, we always get twice that force at the lever end.

Taking this to the cord equivalent, if we have a nipping loop loaded 1000lb one side vs 500lb the other side and 500lb on a cord through its nip.  If the CF is sufficient that the nipped rope cannot slip, then effectively we have made a cord lever - the grip exceeds the force attempting to withdraw the nipped cord.  The lever principle applies then across the whole range of applied forces - drop it to 200lb vs 100lb + 100lb, and it will still grip because we have reduced the load as well as the grip, but we have not changed the ration of grip to load.  Even right down to 2lb vs 1lb +1lb the ratio still stays in favour of the grip beating the load.

So long as the CF is sufficient to give a favourable advantage of grip over load, the nipped cord cannot slip under any load from zero up to the failure point, assuming, as I stated at the onset, that the knot is dressed and set - i.e. ready for work.  [ of course, this explanation also shows that it is the bight legs that are the critical aspects of the bight, the collar is nearly trivial]

And while I am on the topic of 'Dressed and Set', I see that on pages 16 and 19 you still carry the decorative forms of the Carrick mats as arguments for structure.  Please, dress and set them into their working forms, then consider your classification.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 01, 2016, 03:45:54 PM
Quote
Wow Mark, I am impressed, that is quite some significant rewrite (restructure) -- for an encore you require two Oil Rig anchor hawsers and a length of Space Elevator ribbon...

Thank you...the pen is mightier than the sword.

Some of Xarax's words are just Greek to me... but, from what I can glean, a good analog of his feelings toward to you can be found in 'Monty Python and the Holy Grail' film starting at 26 min 30 seconds. Have a look to get a feel for it...

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 01, 2016, 08:32:52 PM
Oh, I wonder what I have done, or what he thinks I have done, to warrant such an opinion.  I thought he was a friend...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 01, 2016, 10:03:28 PM
I agree that the 'capstan effect' is overstated ... but, i have to juggle different viewpoints.

I am in direct contact with Constant Xarax and
am presently digesting his comprehensive email to me.

i am trying to find some ground 'half-way' (or middle ground) here....
having reviewed some early feedback and also going back to the drawing board...
the 'capstan effect' plays a role during initial stages of loading,
 but the compressive power of the nipping loop takes over and dominates
.

So the middle ground here is that there is a 'capstan effect',
but, it is not a significant factor at higher loading where the compressive
power of the nipping loop is the dominant force.
That is your problem, then!  The issue at hand isn't what
anyone thinks so much as what IS.  Anyone can conjecture
this or that, but some things can be better analyzed, and
in this case one could better think about this "myth" (shall
we call it?).  Try testing the conjecture with a pulley for
the collar, pulley anchored in parallel with S.Part (so to keep
collar at a reasonably matching aspect to what it would
have in the knot, and having that turNip-stabilizing effect)
and then loading it :: see any "lack-of-capstan-effect" effect?!
--that would be cordage moving around the frictionless
pulley, if the conjecture has merit.

Trying this myself, in reply, with 1/2" solid-braid nylon
(old but pretty sort & flexible, moderately slick?) and
a 5"-dia clothesline pulley (as measured from rope centers),
I see turning upon loading, but it seems to me that this
much comes in some effect of pulling the pulley'd collar
away from the turNip, and then of course the tail is much
less secured than the loaded-in-eye eye-leg collar part,
so the tail is pulled up into the pulley.  With some little
adjustment to try to stem such seeming mis-match of
loads on S.Part & turNip & pulley'd collar, I get little or
no movement.
I do NOT see movement of the eye leg through the nip.

If anything, it is at higher forces that some slippage of
the collaring eye leg can occur and for which there could
be seen some effect at the friction & bending at the
collar; but this could be hard to measure-discern vs.
simple resistance from the nipped tail --i.e., tension
on the collar legs coming equally by the S.Part pulling
into it ... . !?


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 01, 2016, 11:19:32 PM
Quote
Oh, I wonder what I have done, or what he thinks I have done, to warrant such an opinion.  I thought he was a friend...

Its a joke Derek...humor... I think he still likes and respects you :)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 02, 2016, 07:58:29 AM
From Dan Lehman:
Quote
Trying this myself, in reply, with 1/2" solid-braid nylon
(old but pretty sort & flexible, moderately slick?) and
a 5"-dia clothesline pulley (as measured from rope centers),
I see turning upon loading, but it seems to me that this
much comes in some effect of pulling the pulley'd collar
away from the turNip, and then of course the tail is much
less secured than the loaded-in-eye eye-leg collar part,
so the tail is pulled up into the pulley.  With some little
adjustment to try to stem such seeming mis-match of
loads on S.Part & turNip & pulley'd collar, I get little or
no movement.

I do NOT see movement of the eye leg through the nip.

Using the rig per the attached photo...when I apply load, there is most definitely tail slippage through/around the pulley.
However, I did notice that as the load increased, the compressive power of the nipping loop became dominant - and inhibited any further slippage.

I repeated this for 30 minutes while sipping a latte (home made) - and each and every time I applied load - the tail slipped through the pulley (up to a point - until the compressive force of the nipping loop overcame and stopped any further slippage.

The rope I used was a Beal 'Joker' EN892 dynamic climbing rope - 9.1mm diameter.

Can you try to repeat my experiment using a similar test jig?

I have also attached a photo showing an oversize collar...I wanted to see the effect of load on this structure (note the scissor-like action of the nipping loop which causes the bight to fold/kink).

EDIT:
I would like to include 3 separate pages dedicated to an individual contributor theories.
The 3 contributors I had in mind are:
1. Dan Lehman
2. Constant Xarax
3. Derek Smith

I hope that you will all agree...and if yes, I need copy from each of you - to fit within an A4 size page. You are free and welcome to use any of my photos to illustrate your point.

I am starting to run out-of-time again...so any copy you can give me will be enthusiastically accepted.

Keep in mind that it will be published and made freely available in the public domain - so as they say... "publish or perish"!
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Sweeney on February 02, 2016, 10:26:36 AM
Using the rig per the attached photo...when I apply load, there is most definitely tail slippage through/around the pulley.
However, I did notice that as the load increased, the compressive power of the nipping loop became dominant - and inhibited any further slippage.

The test rig is interesting in that it allows for (virtually) free movement of the collar but how was the load applied? If a pulley is used at the bottom of the loop so that closure of the nipping loop and slippage of the tail occur at the same time without friction at the point the load is applied then in stiff rope I suspect that the end will slip out completely as the force required to tighten the nipping loop becomes greater than that applied to the collar (that is an untested assumption however). The opposite would be to clamp the load to the loop allowing no movement between the 2 legs so that the slippage of the tail can only occur until the nipping loop has tightened which is what I think is being observed here though not as extreme as this case.

Sweeney
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on February 02, 2016, 10:30:40 AM
Hi Mark (and all),

I think it should be put more special emphasis on the stabilization of the nipping loop (we can find this stabilization in the standard bowline (#1010) in the Myrtle and in the Eskimo (what about the Sheet Bend?)).
For major emphasis (again!?) you could use ABoK #1154 as Sheepshank Knot.
(my 2 cents)
ciao,
s.
p.s.
p.3 missing ")" ... Scott Safier (USA
p.31 what about the "?"  .... Reversed Water Bowline? [Regular view]
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 02, 2016, 12:18:01 PM
Dressed and Set

A working knot does not, indeed generally cannot, function as intended until it has been Dressed and Set.

One of the reasons I would never use a bowline as my primary tie in  is because of its propensity to Un-Set and Un-Dress itself.  Put simply, the Bowline is not designed to be 'self competent'.  The Constrictor is 'self competent' because once Dressed and Set it has a self clamping function that prevents unravelling.  The Carrick is 'self competent' because any loading automatically causes the knot to Self Dress and Self Set. [In this respect, the Carrick is genuinely the King of all working knots - or should that be Queen, because it is just so damn good looking?]

But the Bowline relies on the tier to dress and set the knot, then load to maintain the nip which in turn is the only way the knot can remain intact and prevent the WE from escaping.

I tried your experiments using a PUL110 with 11mm Kernmantle dynamic.  It was impossible to dress and set the bowline because the natural stiffness of the rope kept the nip open and the absence of a dressed collar allowed the nip to open further.  Yes, every time I tensioned this 'open' knot, the WE flowed easily out of the open nip and around the SP.  However, once I manually closed the nip, the negative cogging of the bight legs immediately arrested flow through the nip and movement around the pulley collar ceased.

So, I repeat my claim - ' in a dressed and set Bowline, there is no Capstan flow in the collar '.

This image demonstrates three things :-

(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20421;image)

The first is that there is no capstan effect - otherwise you would have seen one collar leg under more tension than the other as the 'suggested' capstan effect gripped the SPart, passing load into it and leaving the other side less loaded.

Hopefully that is now the death of the Capstan argument.

The second thing this images shows, is that the collar is not the key of the bight component, rather, it is the legs of the bight that are responsible for stabilising the nipping helix.  The partial load from the returning loop leg, negatively cogging into the WE, makes this tensioned pair a turning load on the nip, which extends through the nip and is in turn partially stabilised by the flow of the bight legs into the collar which retains the bight in place.

The third and actually the most important thing this image shows is the critical importance of Dressing and Setting a working knot.  In fact, I would go so far as to say that this image is not a Bowline because it us not yet correctly dressed and set.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 02, 2016, 03:16:42 PM
(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20415;image)

This is not only a Bowline, it is also a Work of Art !!!

You know the way sometimes you look at something and first impression is Eue - that's ugly...  well that is how this first hit me - then I looked closer.

As Alpineer explains, it is a #1010 with a HH top and bottom and a final tuck of the WE into the Eye.

Looking at this knot it is dawning on me that its creator is a person who lives and works with working knots.  I would like to get to know them because I think I could learn a lot from them.

The first HH around an eye leg and then tucked through the tightly dressed collar, secures the WE  without risking jamming the knot when it is heavily loaded.  The HH made tightly against some other component or object is essentially the nipping turn (hitch) found in the Sheetbend, it is surprisingly 'self competent', particularly with the WE further secured within the collar.

But this knot does not stop there, it continues to build on the easy application of another HH behind the well dressed collar.  The result is to further stabilise the collar against the often seen deformation under load.

But it is the final two twists that nearly give me goosebumps.  The first HH closed the gap between the two loaded legs of the eye, so taking the tail and wedging it against the side of this HH, it forces the sides of the eye apart, so the load on the eye 'squeezes' the end, holding it gently, yet firmly while giving even more competence to the HH.  And the goosebumps !! look how exactly the tier has judged the amount of rope needed to just fit that tail into the pinch, without a flapping tail to get caught up, yet pinched so gently that nothing is going to bind up with heavy loading.

I'm putting these images into my 'Admiration' Scrapbook.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 02, 2016, 06:44:30 PM
From Dan Lehman:
Quote
Trying this myself, in reply, with 1/2" solid-braid nylon
(old but pretty sort & flexible, moderately slick?) and
a 5"-dia clothesline pulley (as measured from rope centers),
I see turning upon loading, but it seems to me that this
much comes in some effect of pulling the pulley'd collar
away from the turNip, and then of course the tail is much
less secured than the loaded-in-eye eye-leg collar part,
so the tail is pulled up into the pulley.  With some little
adjustment to try to stem such seeming mis-match of
loads on S.Part & turNip & pulley'd collar, I get little or
no movement.

I do NOT see movement of the eye leg through the nip.

Using the rig per the attached photo...when I apply load, there is most definitely tail slippage through/around the pulley.
However, I did notice that as the load increased, the compressive power of the nipping loop became dominant - and inhibited any further slippage.

I repeated this for 30 minutes while sipping a latte (home made) - and each and every time I applied load - the tail slipped through the pulley (up to a point - until the compressive force of the nipping loop overcame and stopped any further slippage.

The rope I used was a Beal 'Joker' EN892 dynamic climbing rope - 9.1mm diameter.

Can you try to repeat my experiment using a similar test jig?

I have also attached a photo showing an oversize collar...I wanted to see the effect of load on this structure (note the scissor-like action of the nipping loop which causes the bight to fold/kink).
??!
I report doing what you do and you reply to that and
ask if I can repeat ... ?!?  WE DID THE SAME THING!
--except for different pulleys (I like yours!), and I had
my pulley eventually INdependent of the S.Part, as
--as written above-- it seems to me that in some
configuration --i.p. y/ours-- there is the effect of
pulling the collar bight (from nipping loop)
which is a different thing than normal bowline action.

So, see if YOU can repeat your testing by arranging for
the knot to assume a decent starting point --i.e., the
colllar-pulley making good effect on orienting the central
nipping loop-- AND THEN LOADING THE S.PART vs. an
anchored eye --the point being to if anything be
pulling the knot upwards, and towards the pulley and
not pulling it (by loading eye) away from the collar.

Now, I did go repeat ... and I am further convinced that
the movement that we have seen is attributable as I've
just said : of the knot being pulled away from the collar
and so the less-secured part --viz., the tail-- is what moves,
rotating our pulleys.  But if one works to avoid this
unnatural loading of parts, to have the collar remain
*unbiased* so to speak, and to load the knot from
the S.Part end mostly, or otherwise arrange for the
pulley'd collar to move with knot, one will not see any
movement betraying some "capstan effect".
Now, in defence of the CE-exists position, I will concede
that we inevitably allow for the nipping turn to become
pretty parallel to the axis of tension and thus turning
the collar legs more perpendicular to it
and thus putting that bending as resistance to their
movement.

Furthermore, I've tried achieving a good knot form
and then holding just the "ongoing eye leg" in making
tension on the knot and then pulling away on the
collar pulley :: BOTH bight legs are pulled through
a sort of rotating nipping loop, and I don't see any
movement of the pulley (which would occur were
the collar legs pulled at different rates).

.:.  I don't see evidence to support a "capstan effect"
to any degree of significance.  It remains just some
conjecture, IMO, and not one I share.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 08, 2016, 03:49:30 AM
Just advising that I am currently undertaking a re-write of the Bowlines paper - and adding a lot of new content plus several additional knot images.

Some quick FAQ's - I have received emails from several individuals - and some people seem to be arriving at their own conclusions regarding what the paper is or isn't. Some of the claims made are wildly inaccurate and just plain wrong.

1. Firstly, this paper is not about discovering and/or analyzing the next new and fabulous tie-in knot for climbing/mountaineering. So if you think that the primary thrust of this paper is to find and promote a new Bowline tie-in knot - you would be wrong.
2. The paper is certainly about Bowlines - and it attempts to find the core components/elements that entitle a knot to awarded the title of 'Bowline'
3. Along the way, some new ideas and concepts are explored and discussed.
4. Some major players - who have been active in the IGKT forum and in particular contributing to this topic - will be quoted (I am sifting through the many pages of written replies and extracting key concepts...).
5. I see myself as the principal architect and editor of the paper - but not the principle knotting expert or theoretician. i see others in that role (not me personally). I like to ask questions and then wait for the responses - and then ask another bunch of questions...and so on - until I can get some sort of clarity on the subject matter. For example; with regard to the 'capstan effect' - I make no decisive claim either way - I just ask the question. I did perform some simple experiment - and it was inconclusive (however, what is conclusive, is that I could observe no capstan effect once the compressive force of the nipping loop was operating. Any 'slippage' that was observed only occurred during initial loading - but even that was 'inconclusive' - in that, sometimes I noticed a little tail creep around the SPart/collar and other times I did not. But I never observed any tail creep around the SPart/collar during moderate or higher loading). Be that as it may, there are some who are strong advocates for a measurable/observable capstan effect - and I need to make sure that their voices are heard too).
6. There are some strong personalities and equally strong opinions that I am trying to work with. I try to be fair to all parties - and be inclusive rather than exclusive when documenting ideas and concepts.
7. Over the years that this project has been crawling long - it has demonstrated to me that there is no uniform agreement over what constitutes a 'Bowline'. So i just keep plugging away - sort of like the Egyptian pyramid builders who chipped away at huge granite blocks...you just have to see the bigger picture :)

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 08, 2016, 07:15:49 PM
1. Firstly, this paper is not about discovering and/or analyzing the next new
and fabulous tie-in knot for climbing/mountaineering.
But is should go to some good effect to set out how
various things that might fall under the casual reference
to "bowline(s)" can be quite different, with consequent
differences in behavior --leading to, naturally, different
conclusions about "the bowline" and showing thus how
the failure to recognize distinct knots causes confusion.

Quote
For example; with regard to the 'capstan effect' :
 I make no decisive claim either way; I just ask the question.
I did perform some simple experiment ... [and I too echoed your effort]
//
Be that as it may, there are some who are strong advocates
for a measurable/observable capstan effect
--and I need to make sure that their voices are heard too)
Here I --and I surmise also Derek, and it should be
you yourself(!) and others(!!)-- will call you out on this
and demand some evidence beyond mere conjecture!
SHOW US THIS OBSERVED MEASUREMENT!
--or else, please do NOT give it credence in publication.
(And we must presume "some" to be "someONE", whom
we've some extensive experience with --with making
unfounded speculations, strongly.)

Quote
- and [my testing of the alleged "capstan effect"] was inconclusive
(however, what is conclusive, is that I could observe no capstan effect
once the compressive force of the nipping loop was operating.
Any 'slippage' that was observed only occurred during initial loading,
but even that was 'inconclusive',  in that, sometimes I noticed a little tail
creep around the SPart/collar and other times I did not. But I never observed
any tail creep around the SPart/collar during moderate or higher loading).
And so too did I initially see, like you, significant tail slippage,
but found a rationale for this (viz., pulling collar away from
the nipping loop), and adjusted my test configuration so as
to avoid this pulling : and then I saw no tail slippage.

(One idea occurs to me now, to try to redress the effect
of removing loading of the put-into-pulley would-be collar:
make an effective collar --so to achieve natural disposition
of the nipping loop-- out of a separate piece of cordage,
anchoring to the "on-going" eye leg.  The point here is
to give less "deflection"/curvature to the would-be collar's
bight legs, to make them more vulnerable to alleged slippage.)

Quote
6. There are some strong personalities and equally strong opinions that I am trying to work with. I try to be fair to all parties - and be inclusive rather than exclusive when documenting ideas and concepts
Stepping aside from personalities, be disinterested and just ask
What is the evidence ? : so far, we have seen the two of us
try to find evidence; what else --esp., from who so strongly asserts
the "capstan effect"?!
You do understand science's demand for repeatable results?!

Quote
7. Over the years that this project has been crawling long - it has demonstrated to me that there is no uniform agreement over what constitutes a 'Bowline'.
However, one can be confident is showing what the bowline
is, and then note other things as sharing this or that aspect,
without purporting to be making a definition of a set, but
just showing how some things (e.g, the turNip) from the
agreed venerable knot are used in other knots, and to what
effect.  Others can cite the exposition in making their own
claims to this or that.

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 10, 2016, 01:11:52 AM
Just announcing that VER 2.4 (10 Feb 2016) is ready for download.

Link: http://www.paci.com.au/knots.php  (located at #2 in the table)

I have undertaken a significant re-write of the content.

Again - please keep in mind at all times that this is still a work-in-progress.

I welcome your considered feedback.

If you require changes to be made - please try to be specific - eg page numbers, the particular text that is a source of irritation etc. And then provide new content so I can copy-paste it!

Of particular interest to me are pages:
[ ] page 7 (a rationale for showing the 'detail' view of a Bowline)
[ ] page 11 (examines the difference between loops and turns) - I need further technical feedback to improve this page please...
[ ] page 15 (ring loading) - I have significantly re-written this page
[ ] page 17 (capstan effect) - a significant re-write (oh dear!)
[ ] page 22 (Myrtle) - new content - need further technical feedback to improve this page please...

and a few other amendments and enhancements...

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on February 10, 2016, 10:27:30 AM

[ ] page 11 (examines the difference between loops and turns) - I need further technical feedback to improve this page please...

[ ] page 22 (Myrtle) - new content - need further technical feedback to improve this page please...


Hi Mark,
(IMHO)
- p.11, maybe it's better to distinguish the right-handed loops (turns) from the left-handed loops (turns) (for reference see Asher, The alternative knot book p.22, I can post a picture about that). In your pictures the "underhand loop" is a right-handed loop, but if you turn it upside-down it does become  an "overhand loop" (but always a right-handed loop), doesn't it?

p.22 about the Myrtle, it is stable if the nipping loop and the tail loop (tail turn) are one right-handed and the other left-handed (or  vice versa).


ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 10, 2016, 12:41:33 PM
Hi Mark,

I have to echo Knotsaver re the Myrtle on p.22.

A Myrtle requires one helix to be 'S' twist and one to be 'Z' twist otherwise it is not stable.

It does not matter which side of the nipping helix the return loop leg enters, provided it's twist is opposite to the twist of the 'Nipping Turn'.

If you take the knot shown as being unstable, leave the entry direction the same, but reverse the twist from 'Z' to 'S', you will see the knot is quite stable.

This is a rather neat example of the importance of the requirement that in the Myrtle, the helix components must have opposite twists.

NB  I see you have added
Quote
Note: This author disagrees that there are ?twin nipping loops? and argues there is only 1 nipping loop

I guess this harps back to the earlier insistence that a 'Nipping Loop' / 'turNip' / 'Nipping Helix' must have both ends loaded.  Yet that definition was made without thought being given to any acceptable degree of differential loading.

In the case of #1010 the loading is ca 2:1  SP:Loop leg.

So, at what point is the differential in loading unacceptable and the 'Nipping Loop' ceases to reflect this apparently critical aspect?

Further, the definition fails to stipulate where this 'loading' comes from.  Obviously, it must resist the load from the opposite end of the nip, but must it be externally generated? Or can it be self generated as when that end is nipped or clamped by some other part of the knot?

And what is some percentage of the load is external and some is from clamping?  When does the definition no longer apply?

Obviously, a 'Nipping Loop' / 'turNip' / 'Nipping Helix' has to be loaded at each end, otherwise when load was applied to one end it would simply flow and exit the knot.  Any force applied to the end will be amplified by the Capstan effect of the turn and so create the compressive nipping force.  But that force can come from clamping the end as well as external tension.

I contend that both components in the Myrtle are 'Nipping Loop' / 'turNip' / 'Nipping Helix' components, but you have dismissed one of them from this group.  What then would you have us call the second functional nipping helix?  And perhaps more importantly, how are you proposing to handle the infinite array of variations of load differential and combinational loading sources?

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 10, 2016, 01:09:19 PM
A bight has two legs, and as the following image shows, they are critically important in the stabilisation of the Nipping Helix  in this loop knot -

(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20421;image)

By contrast, the 'Collar', claimed on p.5 to be "an important component of a Bowline" is shown to be trivial, little more than the means to return the second bight leg to its partner, in their joint stabilisation of the nipping helix.

The bight legs are important in their role of stabilising / resisting the turning moment of the loaded nipping helix, while the role of the collar is trivial.

We have at last put to bed the imagined (yet strenuously argued) role of the capstan effect in the collar, but we are still hanging on to the claimed 'importance' of the collar in the Bowline functionality.

OK, if it is more important than the stabilising function of the bight legs, then let someone post here either proof or logical argument of this importance.

Yes, it can add a small amount of counter rotational stabilisation to the nipping helix, but as this image shows, it is trivial to the extent that the knot can handle all the loading without significant help from the collar torque.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on February 10, 2016, 03:32:29 PM
A bight has two legs, and as the following image shows, they are critically important in the stabilisation of the Nipping Helix  in this loop knot -
By contrast, the 'Collar', claimed on p.5 to be "an important component of a Bowline" is shown to be trivial, little more than the means to return the second bight leg to its partner, in their joint stabilisation of the nipping helix.

The bight legs are important in their role of stabilising / resisting the turning moment of the loaded nipping helix, while the role of the collar is trivial.

Derek

Hi Derek,
what about if you use a carabiner ticker than the one in the picture? (you can consider it a "micro" ring loading).
I think the nipping loop will be not stable any longer! I think the collar helps to stabilize the nipping loop (see the components under load (p.28), what happens without the collar?).
In the Sheepshank the nipping loop is stabilized by the bight and by the torsion determined by the other structure (second bight and second nipping loop).
In the Gleipnir the stabilization is determined by the two ends entering the nipping loop from opposite sides (and by their tension).
I think the collar is an important component for the stabilization of the nipping loop.
ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 10, 2016, 06:43:54 PM
Hi Mark, I have to echo Knotsaver re the Myrtle on p.22.
A Myrtle requires one helix to be 'S' twist and one to be 'Z' twist otherwise it is not stable.

It does not matter which side of the nipping helix the return loop leg enters,
provided it's twist is opposite to the twist of the 'Nipping Turn'.
But it matters definitionally as to whether the formed knot
is a "Myrtle" (or else an "anti-bowline", one sometime called
the "Swedish bwl." & " bollard loop" per an IGKT article
--and is the Myrtle in reverse (i.e., loaded tail qua S.Part)).
In the latter case, I've seen like-handed knots, and the tail
is nicely presented for seizing/taping to the S.Part; set well,
the knot is stable --more so than for the Myrtle.

Quote
NB  I see you have added
Quote
Note: This author disagrees that there are "twin nipping loops" and argues there is only 1 nipping loop

I guess this harps back to the earlier insistence that a 'Nipping Loop' / 'turNip' / 'Nipping Helix' must have both ends loaded.  Yet that definition was made without thought being given to any acceptable degree of differential loading.

In the case of #1010 the loading is ca 2:1  SP:Loop leg.

So, at what point is the differential in loading unacceptable and the 'Nipping Loop' ceases to reflect this apparently critical aspect?
...
Derek
One might consider that if the main "nipping loop" actually
*nips* then the nipped would-be-loop parts canNOT --for
they are nipped and immobilized thus!?  They do have effect
in the unloaded but set knot in keeping it tied/secure,
but on loading, one could even see space open within the
"would-be" loop's enclosure --I know this to be true of the
"end-binding" loop of the EBDB, and so try to set that quite
tight in anticipation of such opening (which comes as loaded
parts that it surrounds diminish in diameter).


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 11, 2016, 04:41:49 PM
VER 2.4a (12 Feb 2016) is uploaded.

Significant changes made:

[ ] page 11 (re-written with new images)
[ ] pages 18+19 swapped
[ ] page 20 (new page and new content)
[ ] page 25 (Myrtle) re-written

Keep in mind that this is still a work-in-progress.

I am starting to run out-of-time again.

I am happy with the way the paper is progressing... a big improvement over the original content from 2013.

I welcome any constructive and considered feedback.

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on February 11, 2016, 06:08:11 PM
Hi Mark.

Thank you once again.

I've no constructive criticism, just an appreciation of your good work!

I think that Alan Lee should be added to the contributors list on Page 3.

I am of the opinion that the ABoK #1010 is "the Bowline" and if an eye knot does not contain its basic configuration, first, then it is an eye knot of some other name/descriptor. I believe it should be that simple.
Possible exceptions that could include the "bowline" moniker are where the nip turn and or collar is doubled, or tied with a bight.

The theory of multiple diameters within the nip turn reducing breakage (Strength increase over the original) has not been proven to my knowledge. I suspect that there will be an increase of torsional, etc., movement within and more rope deformity that can lead to destructive force.

I agree that strength increase is not a particular requisite and that the main gain of the multiple passes through the nip structure could lead to better security, mainly because of increased collar stability and tail capture.

Just some of my thoughts on it.

Thank you.

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 11, 2016, 08:19:22 PM
Mark,

You state on p.17 that "The role of the Collar is very important in a Bowline".

If it is so important, it will presumably be relatively easy to catalogue its functions and how loss of these collar functions destroys the viability of the knot.

I can offer - The Bight is very important in a Bowline because it counters the turning moment created by the loaded Nipping Helix.  The bight collaring the SP offers a small degree of stabilisation of the Bight in low load situations.

I certainly can not think of any reason to claim the Bight Collar to be important, while ignoring the Bight legs.

While I am happy to continue to contribute to the discussion here on the Forum, as you persist in stressing the importance of the collar without first justifying this claim, I feel it necessary to ask you to remove my name from your document.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 12, 2016, 01:34:12 AM
Quote
as you persist in stressing the importance of the collar without first justifying this claim, I feel it necessary to ask you to remove my name from your document

Hmmmmmmmmmmmm...

I am not used to being given ultimatums.

I can say that I am not a miracle worker; this paper is difficult to write and difficult to get technically correct.

Someone once told me... "You can please some of the people some of the time - but you can't please all of the people all of the time".

I am presently working on content to prove the importance of the collar as follows:
1. All Bowlines have a collar structure - I am unable to find an example of a Bowline where it is absent.
2. The Sheepshank does not have a collar - and as load increases, the scissor-like action of the nipping loop causes the bight to fold/kink. As load continues to increase, the Sheepshank becomes unstable. I find this interesting...this suggests that the SPart acts as a 'bracing post' - in that the collar is braced against the SPart. If the sheepshank had a collar (ie 2 collars - one for each bight) it would mimic the function of a Bowline - but, since it has no collar structure, it degenerates and becomes unstable.
3. If I tied #1010 but left the bight in free space (with no U turn around the SPart) - no collar - would it still be a Bowline? (refer to attached image).
4. I posit that the collar acts as a stabilizing element for the bight - when there is no collar, the bight component is unstable.

I would ask that you consider the attached image... Is it a Bowline?

Furthermore, you are demanding that I supply proof of the importance/significance of the collar in a Bowline - that is, you are placing the onus of proof on me. I would like to reverse the onus of proof. I draw your attention to the Sheepshank and to the attached images as the basis for argument.

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 12, 2016, 07:50:32 AM
VER 2.4c (12 Feb 2016) is uploaded.

Significant improvements made:

[ ] page 2 (re-written)
[ ] page 14 (new content examining the role of the collar)
[ ] pages 34-40 (alterations and enhancements + some additional new content)

Derek Smith has been deleted as a contributor.

Alan Lee has been added as a contributor (please advise if you want to be deleted).

Keep in mind that this is still a work-in-progress.

I welcome any constructive and considered feedback.

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 12, 2016, 08:11:43 AM
If it is so important, it will presumably be relatively easy to catalogue
its functions and how loss of these collar functions destroys the viability of the knot.
//
Derek
WOW!  I cannot believe I'm reading this!

So, Derek, you'd happily put your life on a collarless
--but with pair of "bight" legs-- bowline and ... ?!
--rap off of Yosemite's famous walls,
moor your just-won-in-the-lottery yacht,
or even tie up a pet dog ?!

Heck, I know that a great many knots books present
the sheepshank as a once-used (and potentially
still useful, though How...? is typically not articulated!)
knotted structure,
but I'm way chary of even employing that --though have
done so, on a short line I step to haul on my pulley (if
things go bad, my foot has a short fall to the ground).

Just when I thought X's musing about some "capstan effect"
was dimming in the view of others, you seem to have ruled
out ANY effect for the collar!    :o
Quick, someone, turn on the lights!  8)


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 12, 2016, 08:25:35 AM
Dan,

I would appreciate your considered feedback on VER 2.4c.

I am starting to bog down... my eyes are bleeding and I am worried about DVT (deep vein thrombosis) from sitting motionless for far too long and pounding a key board.

...

Anyhow, I am still trying to understand Xarax's private emails re the 'capstan effect' and ways to devise a better test rig. Be that as it may, my test rigs have proved either inconclusive or that there is no capstan effect once the compressive force of the nipping loop has engaged. I would have thought that the rotating drum (sheave) of a pulley would reveal a capstan effect (ie slippage ought to have occurred) if it existed - but it did not.

However, my observations lead me to believe that the collar is nevertheless important as a bracing post for the bight component. Please look at the images on page 14.

I also posit that the attached image is not a Bowline - because there is no collar.

EDIT: I might add that without the collar - as load increases, I found that not only does the bight fold down, the nipping loop also is vulnerable to collapse - in that once a certain load threshold is reached - the helix degenerates and collapses.

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 12, 2016, 08:52:18 AM
I am worried about DVT (deep vein thrombosis) from sitting motionless for far too long and pounding a key board.
The shocking news in the past couple? --just-- years
about supposed bad effects of sitting (not a new thing
to do, after all!) came w/o any good indication of Why...?
--but I surmised it must have to do with circulation.
To that end, at least get up and do some squats (which
might prove beneficial otherwise, too!).  Some folks arrange
to be able to "pound ..." whilst standing.

Quote
Anyhow, I am still trying to understand Xarax's private emails re the
'capstan effect' and ways to devise a better test rig.
Which implies that HE hasn't (tested...) !
Frankly, I was impressed we both got into it, and IMO
did a fair job --you needed to separate the attachment
of the pulley from the S.Part, which pulled it away ... .
I'll be happy to hear of other testing.
(Big news currently is that seeing/hearing/*feeling* of
bent space-time per Einstein after black holes collided?!)


 ;)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on February 12, 2016, 10:17:10 AM
Hi Mark,
IMHO (I don't want to reinvent the wheel  ;) but...)

without a collar it's unstable the nipping loop, not the bight.
We are able to stabilize the nipping loop (in ABoK #1010) by the whole bight (legs + collar).

To my mind the first 3 key components are:

1. a nipping loop
2. a (nipping loop) stabilizer
3. a fixed eye

The term "fixed" hides something: how do we obtain a fixed eye?
I think by a stabilized nipping loop!

About the Myrtle (p. 26) you say: "The structure is stable....This occurs when  the 'returning eye leg' enters the nipping loop from the SPart side (in the same way that a standard #1010 Bowline is formed)."
Please look at the attached picture: in this (wrong) Myrtle the 'returning eye leg' enters the nipping loop from the SPart side, but it's unstable. because the 2 loops (turns) are both right-handed...
That holds (mutatis mutandis) when the 'returning eye leg' enters the nipping loop from the same side as the ongoing eye leg - rather than from the opposite SPart side: we can obtain a stable (quite stable, more stable...I don't know) structure by 2 loops one right-handed and the other left-handed.
(this reminds me the 'Boobash' (Boobashley? Boobasher? :) ) ABoK #1445).

ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 12, 2016, 10:31:16 AM
Hello knotsaver,

Many thanks for feedback - and yes, I wasn't all that pleased with my attempted re-write of that page (Myrtle). Derek's S and Z twists were not entirely satisfactory to me - I was looking for another analogy/description...and you're right in what you say so it ought to be included. Opposite chirality (eg left-right instead of left-left).

 And yes, I forgot to include commentary re the other major effect of the collar - is that it aids in maintaining a stable nipping loop - without the collar, the bight kinks and folds down which in turn causes the nipping loop (a helix) to degenerate.

Also, may I include you as a contributor?

Thanks,

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 12, 2016, 02:13:21 PM
If it is so important, it will presumably be relatively easy to catalogue
its functions and how loss of these collar functions destroys the viability of the knot.
//
Derek
WOW!  I cannot believe I'm reading this!

So, Derek, you'd happily put your life on a collarless
--but with pair of "bight" legs-- bowline and ... ?!
--rap off of Yosemite's famous walls,
moor your just-won-in-the-lottery yacht,
or even tie up a pet dog ?!

Heck, I know that a great many knots books present
the sheepshank as a once-used (and potentially
still useful, though How...? is typically not articulated!)
knotted structure,
but I'm way chary of even employing that --though have
done so, on a short line I step to haul on my pulley (if
things go bad, my foot has a short fall to the ground).

Just when I thought X's musing about some "capstan effect"
was dimming in the view of others, you seem to have ruled
out ANY effect for the collar!    :o
Quick, someone, turn on the lights!  8)


--dl*
====

Dan,

That is beneath you.  You know full well I have not ruled out any effect of the collar, and you also know full well what I actually stated, but to refresh your memory, here it is again --

Quote
The Bight is very important in a Bowline because it counters the turning moment created by the loaded Nipping Helix.  The bight collaring the SP offers a small degree of stabilisation of the Bight in low load situations.

Besides, this, with or without collar, you would not catch me "--rap[ing] off of Yosemite's famous walls" with any form of #1010, and I have made the point many times before that I would NEVER climb with the Bowline as my safety knot.

Having said that, Oh what I would give for just the chance to rap down those amazing faces - sadly though, not to be...  and if I tied up any of my dogs with any form of Bowline, they would chew through the rope in seconds - 'Very Important Collar' or not.

Seriously though, obviously the bight 'collar' has to be anchored somewhere, and the Bowline is such a minimalist knot, there is very little elsewhere to park it.  But the thrust of my statement was to challenge Mark, or any other Knotbotherers, to come up with a viable reason for giving the collar such importance, and the argument so far given of ' All Bowlines have a collar ' is circular, and does not cut it as being more functionally important than the function of the bight legs, without which there would be no knot, and then we would see just how 'Important' that collar really is...

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 12, 2016, 02:59:42 PM
VER 2.4d is ready for download.

Change log:
[ ] page 12 + 13 (some minor changes to include detail of the collar)
[ ] page 14 + 15  (added new wording to include details about the collar)
[ ] page 26: complete re-write (Myrtle content)

Feedback / comments are welcome.

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 12, 2016, 03:10:34 PM
Quote
as you persist in stressing the importance of the collar without first justifying this claim, I feel it necessary to ask you to remove my name from your document

Hmmmmmmmmmmmm...

I am not used to being given ultimatums.

I can say that I am not a miracle worker; this paper is difficult to write and difficult to get technically correct.

Someone once told me... "You can please some of the people some of the time - but you can't please all of the people all of the time".

I am presently working on content to prove the importance of the collar as follows:
1. All Bowlines have a collar structure - I am unable to find an example of a Bowline where it is absent.
2. The Sheepshank does not have a collar - and as load increases, the scissor-like action of the nipping loop causes the bight to fold/kink. As load continues to increase, the Sheepshank becomes unstable. I find this interesting...this suggests that the SPart acts as a 'bracing post' - in that the collar is braced against the SPart. If the sheepshank had a collar (ie 2 collars - one for each bight) it would mimic the function of a Bowline - but, since it has no collar structure, it degenerates and becomes unstable.
3. If I tied #1010 but left the bight in free space (with no U turn around the SPart) - no collar - would it still be a Bowline? (refer to attached image).
4. I posit that the collar acts as a stabilizing element for the bight - when there is no collar, the bight component is unstable.

I would ask that you consider the attached image... Is it a Bowline?

Furthermore, you are demanding that I supply proof of the importance/significance of the collar in a Bowline - that is, you are placing the onus of proof on me. I would like to reverse the onus of proof. I draw your attention to the Sheepshank and to the attached images as the basis for argument.

Mark

Hi Mark,

The stress certainly seems to be getting to you, so my advice to you is - Calm down and enjoy the Project.

I did not give you any form of ultimatum - I ASKED you - with a please, to remove my name from the document.  Thank you for doing this for me.

I offered you an alternative statement regarding the Bight component which redirected the priority from collar to legs, but acknowledged the lesser function of the collar in stabilising the bight into the nipping helix.  I am pleased to see that you are now also adopting this position in point 4. above.

That blood you see in your eyes must be the 'red haze', because you have turned a simple request to generate substantiation for the emphasis placed on the collar being 'Very important', into the suggestion that I am 'demanding you supply proof'.  Absolutely not the case...  mostly because I don't think anyone can supply such proof, so it would have been stupid of me to demand anything of the sort.

So, just a confirmation - I am not demanding anything, nor threatening any ultimatums.

Getting on with the present two points of contention though - Collar importance and Capstan effect - this lovely emage you provided earlier -

(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20421;image)

supplies all the proof needed to put both areas of contention to bed.

Capstan Effect :- If there were any significant capstan effect in this knot, then one leg of the collar would be under more tension than the other - this would be apparent as one side being tighter and shorter than the other.  No such effect is seen, demonstrating that in this cord, there is no significant Capstan effect at the collar.

Important Collar Effect :- The two major components of this working knot are the nipping helix and the Bight legs - they are both under load and the knot would cease to exist if either were not present.  By contrast, in this example the collar is dysfunctional.  However, in a working knot, loosening and lateral forces are countered by the presence of the collar.  It has a function, just not as important a function as the nip and the legs.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 13, 2016, 12:11:26 AM
Quote
The stress certainly seems to be getting to you, so my advice to you is - Calm down and enjoy the Project.

Your invention of some imagined situation is wrong.

Quote
That blood you see in your eyes must be the 'red haze',

Another interesting and imagined situation... the only red haze I see is the effect of rubbing my eyes after staring at a LCD computer screen for too long.

...

The 'wonderful' image you like to keep recycling actually proves the importance of the collar and how it functions as a 'bracing post' for the bight. I would suggest you have a look at page 14.

In reply, I also like to recycle my own image (attached).
The question is:  Is it a Bowline?

This question is what I call a reversal of the onus of proof. And I like asking this type of question because it alters ones perspective.

[ ] If you answer 'No' - there must be a reason why. And your answer would be interesting.

[ ] If you answer 'Yes' - this would indicate that your requirements to fulfill the definition of a 'Bowline' differs markedly from the standard #1010.

For me, the answer must strictly be in the negative - because without a collar, the nipping loop will become unstable and then collapse and fail (because the bight is not braced against the SPart, it will kink and fold - which in turn triggers the collapse of the nipping loop).

I also commented earlier that I have yet to see a Bowline that has no collar - although one may regard this observation as too simplistic - at the same time, it is surprisingly powerful.
If indeed such a Bowline (with no collar) exists - I would very much like to see it.

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 13, 2016, 12:55:54 AM

Another interesting and imagined situation... the only red haze I see is the effect of rubbing my eyes after staring at a LCD computer screen for too long.

Mark

LOL  -  OK, point taken.

Quote
I also commented earlier that I have yet to see a Bowline that has no collar - although one may regard this observation as too simplistic - at the same time, it is surprisingly powerful.
If indeed such a Bowline (with no collar) exists - I would very much like to see it.

(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20460;image)

By your current definition in 2.4d, no this is not a bwl. because it has no collar.

By the definition I offered earlier, no it is not a bwl. because it has no bight component stabilised against the SP.

So can we take this exercise one step further.  Take a standard #1010, but make it with a long WE.  Now cut off the SP and make it the WE and load the SP.

Exactly the same knot, but we have just swapped the function of the SP and WE.

Is this now a bwl.?

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 13, 2016, 01:20:25 AM
Quote
Take a standard #1010, but make it with a long WE

This part makes sense.

Quote
Now cut off the SP and make it the WE and load the SP.

This part doesn't (in red)...

Did you mean; "and load the eye while holding the new SPart (formerly WE)"?

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: enhaut on February 13, 2016, 01:59:46 AM
@ agent
Your paper is well written, the layout and the photos are great; but for me its too much on the conservative side. Things evolved. #1010 was the first stage of the rocket let's move on please.
In putting too much insistence on the strict definition of the bowline we are gonna miss the "what the bowline have morphed into"
The bowline is a butterfly.
 
My two cents;

A bowline consists of ;
a S Part (single,double,triple...)
a nipping loop ( any kind of, simple, doubled or helicoidal)
the loop  (single double triple...)
a collar  (single double triple or helicoidal) after the returning eye-leg is nipped we got to secure the tail dont we? Plenty clever solutions have been found your paper demonstrates a few.

I would say that any loop depending on a nipping mecanism (any) structure who hold the tension without loosing its primal function deserves the name;

So that why your Project should by entitled;

"Analysis of the bowline and its derivatives"
                       
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 13, 2016, 05:50:39 AM
To my mind the first 3 key components are:

1. a nipping loop
2. a (nipping loop) stabilizer
3. a fixed eye

The term "fixed" hides something: how do we obtain a fixed eye?
I think by a stabilized nipping loop!
I think that you have two components and a result,
in a sense.  A bowline is an eye knot (I don't know
what an "unfixed" eye is --or is it what should be
called "noose"?!), and what distinguishes it from other
such knots is what we're debating.  Your list above
approximates what I've said.  (One might think we
could leave it at "nipping loop", for it that were NOT
stabilized, that would not BE !)

Quote
About the Myrtle (p. 26) you say: "The structure is stable....This occurs when  the 'returning eye leg' enters the nipping loop from the SPart side (in the same way that a standard #1010 Bowline is formed)."
Yes : the distinction cited is one I use to separate
"bowlines" from "anti-bowlines", nothing more;
and stability of these you cite is just as you describe
(and IMO the anti-bowline can fare better with the
same-handed loops, though it's inferior to having
them opposite-handed; the Myrtle-like knot is worse).

Quote
(this reminds me the 'Boobash' (Boobashley? Boobasher? :) ) ABoK #1445).
Though that name doesn't occur there, does it!?

I more or less took AshER to task on this (or meant to),
and so expand "Ash" with an "er" not "ley", after I confirmed
my assessment with testing in which his alleged okay knot
slipped so much that the tester gave up on it!
(tested in 1/4" laid nylon rope)

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 13, 2016, 07:41:48 AM
Quote
I also commented earlier that I have yet to see a Bowline that has no collar
?!  Isn't that because you've defined "bowline"
to have a collar --and filter out anything else?!

Otherwise, Myrtle qualifies --or why not?
MY position (tentative, to see what falls in/out and
so on) is that it's good to define/articulate/identify
the set of knots that have a "central nipping loop",
for which I'm willing to use the name "bowlines".


Quote
too simplistic
Mr. LanguageMan here : "simplisitic" has pejorative sense,
and thus "too" is unwanted; "simple" would work.

Quote
Quote
If indeed such a Bowline (with no collar) exists - I would very much like to see it.
...
So can we take this exercise one step further.  Take a standard #1010,
but make it with a long WE.  Now cut off the SP and make it the WE and load the SP.
Occam cuts off your "cut off" :: simply (not "simplistically", nb!) put,
load #1010 in reverse --by the tail vs. the eye, and see
whether that tickles your fancy!

Firstly, NB : one has to define --this doesn't come with
"1010"/"bowline"(!)-- on which side of the eye does
the newly loaded tail pass !!  (This sort of thing pops
up if wanting to *mathematize* the knot into a
closed loop.)
.:.  Orient the tail-to-be-S.Part so that it crosses over
the eye legs as it would from the position it is drawn
into by the pull of the S.Part --in the direction one would
take it in making the "Yosemitie" finish; this way one
gets more of a loop than helix in the newly become
nipping former collar/bight!

In either case, IMO, this reversed bowline wants
to flaunt a helix and not a loop, but tight setting
might staunch that, to some degree, anyway.
And it counts as a (pseudo/quasi?) "anti-bowline"
as the "returning eye leg" enters from the side
of the nipping loop of the "ongoing eye leg" unlike
for #1010.

It's hardly "Exactly the same knot," but AS we have
just swapped the function of the SP and WE.

Is this now a bwl.?  Well, IMO it can be forced to hold,
at least in this small cord I'm working with now, a nipping
loop, though that does want to open.

Now, as for a "collar", hmmm, I think not?
The nipping loop is held more or less in position
by the nipped tail.  And I think this is your point?!
(good show)

BTW, such a knot has been presented in KM and was
discovered by me on my own, with the simple aim of
*choking* the base of a nipping loop and stuffing it
with diameters to both swell it and stabilize it.  It
perhaps was shown with a slip-bight so stuffed,
in hopes of quick untying?!


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 13, 2016, 10:52:25 AM
Sorry, it was late and I was not clear.

I meant simply exchange the functions of the WE and the SP.

In doing so, we now have the bight collar around the WE and a nipping helix which is loaded only by one loop leg.  The SP no longer has a bight collar, and instead feeds into the nipping helix as a bight leg, on its way to a bight collar around the WE.

Would I be right Mark in assuming this reversal of leg functions now fails your definition on p. 12 (2.4d)

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on February 14, 2016, 12:13:17 AM
To my mind the first 3 key components are:

1. a nipping loop
2. a (nipping loop) stabilizer
3. a fixed eye

The term "fixed" hides something: how do we obtain a fixed eye?
I think by a stabilized nipping loop!
I think that you have two components and a result,

Yes, the stability of the eye is a result, the friction forces acting in the completed (well tied) bowline determine the fixed (not slipping) eye.
The friction forces are generated between contacting surfaces and now I see Capstan effect everywhere in a standard bowline.
- In a well-tied (standard) bowline the nipping loop doesn't lay on a single plane (the bight (and especially the collar) makes the nipping loop do a torsion) and the returning eye leg goes through a "chicane" (a double deflection) in the nipping loop (Capstan effect in the nipping loop?).
- The nipping loop has two degeneration tendencies:
1. the helix can open up
2. the nipping loop can roll (walk).
(Without a collar) the first degeneration occurs when the ongoing leg (the nipping loop leg) is loaded much more than the return eye leg. The second degeneration occurs when the returning eye leg is loaded much more than the ongoing eye leg (I could draw a picture of the experiment I made).
In a well tied standard bowline these events don't occur and the load of the standing end is distributed between the ongoing eye leg and the returning eye leg (Capstan effect of the nipping loop?)

---


Quote from: Dan_Lehman
Quote
(this reminds me of the 'Boobash' (Boobashley? Boobasher? :) ) ABoK #1445).
Though that name doesn't occur there, does it!?

No, the name doesn't occur there. I was referring to this
http://igkt.net/sm/index.php?topic=4480.msg36276#msg36276
;)

ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 14, 2016, 05:37:50 AM
Quote
Would I be right Mark in assuming this reversal of leg functions now fails your definition on p. 12 (2.4d)

Derek

I get the distinct feeling that you are attempting to extract a sort of confession from me for a "aha" kodak moment.

Your argument is non-sensical - as it implies a loading profile that simply doesn't exist - it is only a thought experiment and not a good one at that. It is like asking me to saw one wing off a plane and then ask me if it can still fly (and then declaring you were right all along). An aircraft needs 2 wings (left and right) to remain stable in flight - that's the way its designed - aerodynamic lift is generated by both wings - and lift is perfectly in balanced in level flight. Spoilers on the wings can alter this lift. Look what happened to space shuttle Columbia when it lost one of its wings...

The Bowline is an eye knot - and the eye is intended to serve as a connective interface to something...like a tree, a climbers harness, a carabiner, etc. The SPart is intended to be subjected to load. The same can be said of #1047 F8 eye knot and one can also conduct thought experiments with that knot - and subject it to non-sensical loading profiles to circumvent the eye.

To answer your specific question, this loading profile isolates the eye...and effectively mimics the core function of a Sheet bend (although the Sheet bend can be tied with tails oriented same side or opposite sides - with same side orientation being the standard practice). I have already stated that in my personal view, there is no 'nipping loop' in a Sheet bend since it is not loaded at both ends.

A better argument is to examine some knot structures that cause people to stop and think - and scratch their heads. Like the #1017 Angler's Loop perhaps?

Another area that is more worthy of attention is the various nipping loops (I refer to them a 'loops' and not 'turns'). Budworth also appears to suggest that a 'turn' - eg a Round turn and 2 half hitches is formed around an object such as a post, a tree, a bollard, a rail, etc. I have not seen this structure called a 'round loop and 2 half hitches'... it is always 'round turn and 2 half hitches.

Note: With regard to the bight performing a 'U turn' around the SPart in a Bowline, in this case - the phrase 'U turn' is referring to a maneuver and not a turn in the strict definition of wrapping around an object.

I am currently struggling with a nipping 'structure' based on a constrictor hitch.

And some are not satisfied with a nipping 'structure' based on a Munter hitch...

Mark

EDIT: Another puzzling 'Bowline' - is #1057 and #1058 (in ABoK). I do not know why Ashley referred to these 2 structures as 'Bowlines'. I do not see evidence of a 'nipping loop' (which is loaded at both ends and can freely act to compress all material enclosed within it) in either knot - and so it immediately must be disqualified from having the title 'Bowline'.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 14, 2016, 06:56:23 AM
I meant simply exchange the functions of the WE and the SP.

In doing so, we now have
the bight collar around the WE
and
a nipping helix which is loaded only by one loop leg. [Could it be otherwise?!]

The SP no longer has a bight collar,
and instead feeds into the nipping helix as a bight leg, [?! What? It is not NOW such.]
on its way to a bight collar around the WE.    [?]
????
I don't follow this at all.
If one begins with #1010 but then *reverses* that
by loading the tail vs. the eye (so that the 1010 S.Part
is now unloaded, qua tail),
one has (variously, but it taking care to set snug...)
--THE NEW PARTS NOW USED IN NAMES THAT FOLLOW--
the (new, mind) S.Part making a nipping loop
(albeit one more prone towards opening into a helix)
that nips the tail,
and its ongoing eye leg on-goes,
and returns to surround & so *choke* the nipping
loop at its crossing point,
and then tuck out through the nipping loop to hold.

I see NO BIGHT ANYthing (in the reversal).


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 14, 2016, 08:10:13 AM
Quote
Would I be right Mark in assuming this reversal of leg functions now fails your definition on p. 12 (2.4d)

Derek

I get the distinct feeling that you are attempting to extract a sort of confession from me for a "aha" kodak moment.

Your argument is non-sensical - as it implies a loading profile that simply doesn't exist - it is only a thought experiment and not a good one at that.
I didn't see it as nonsensical, and it's a loading that
defines a NEW knot, one that could be started from
the bowline --and one that, as I emphasized earlier,
wasn't completely defined by Derek as the "long" tail
must cross the eye one side or the other.

What I find nonsensical is Derek's description of what
his recipe yields : I don't follow his words, there.
What I do see, which fits his point --as I also noted
previously--, is that the reversed bowline has its
nipping loop NOT stabilized by any collar but by the
draw of the "choking turn around its crossing point
(depends on that tail-to-SPart orientation) and the
nipped tail (which part had been 1010's SPart).

But I don't follow any logic that somehow by doing
this reversed loading one can lay claim to "bowline"
or cite that knot's parts in discussing the new as
though they continue to exist as they were.

I also don't follow your interpretation of what Derek's simple
recipe yields, either:
Quote
To answer your specific question, this loading profile isolates the eye...
and effectively mimics the core function of a Sheet bend (although the Sheet bend can
be tied with tails oriented same side or opposite sides - with same side orientation being
the standard practice). I have already stated that in my personal view, there is no
'nipping loop' in a Sheet bend since it is not loaded at both ends.
"isolates the eye and ... mimics the ... sheet bend" ???
No, it loads the 1010 tail VICE the S.Part in opposition
to the eye.  And with reasonable setting, the once collar
becomes a nipping loop; the once nipping loop becomes
some wrap-around-&-tuck structure.

WhaTHEck is everyonElse DOING out there?   :o    ::)   ???


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 14, 2016, 08:16:09 AM
Here is one that may generate some interest... #1080

The question is: Does it have 1 nipping loop or 2 nipping loops?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 14, 2016, 11:20:10 AM
Here is one that may generate some interest... #1080
(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20473;image)
The question is: Does it have 1 nipping loop or 2 nipping loops?

It has one - because only one is loaded both ends.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 14, 2016, 11:37:33 AM
Well Derek, you see - I find #1080 to be a very interesting structure.

I personally only see 1 nipping loop.

But I'm not sure if you are just saying there is 1 (but really think there are 2 nipping loops)! The requirement that both ends of the nipping loop be loaded is my theory (and I think Xarax's). But I have a distinct impression that you disagree - and that's fine. So that's why I think #1080 is interesting to analyse.

To me - if this can be definitively answered, it would help us to make forward progress.

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: DerekSmith on February 14, 2016, 08:52:39 PM
It worries me Mark that you think I am trying to trap you with, as you call it, an "aha" Kodak moment, or that I am lying over there being one or two nipping loops - why would I do that?  How would it carry our search for clarification forward?

Yes, you have stated that the definition you intend to use is that both ends of the nipping helix must be loaded, and in the example in point, there is only one structure that satisfies this requirement.

I have stated and given examples of how clamping one end of a nipping helix is sufficient to generate a nip if the unclamped end is loaded (the misplaced capstan effect). but in this knot example, the second helix is loaded only by the second loop, its other end is neither clamped nor loaded, so it fails not only your definition of a nipping helix, but mine as well.

[NB as the return leg of the second loop enters the nip of the nipping helix before making its own turn, it is probable that this second helix is not loaded on either end]

Is this answered sufficiently for you to feel confident that I am not attempting to lead you into some logic trap?  But then, if I was being that clever, and did manage to prove some point to you - would that not be a good thing?  A step forward towards consensus.

But, one aspect of the Bowline I will put forward, is that - the Bowline contains a nipping helix that must be loaded by the primary source of load, i.e. the SPart.  i.e. the greatest load differential available should be impressed across the primary gripping engine of this knot.

Derek
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 15, 2016, 07:27:30 AM
VER 2.4e is ready for download.

A major re-write and re-organisation.

Several new images added and some older images replaced.

Still a work in progress...

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alanleeknots on February 15, 2016, 10:26:57 AM
Hi Mark,
        I like to delete my name on the contributor page, I did not contribute any discussion on the theory side,
        I only have a few knots.beside it you are the one found the use for Lee- Zep X eye knot, you guys have more credit than me.
        Any way thanks for include my knots in you Bowline paper.
        Your bowline paper look great, it is no an easy task, I appreciate your effort making this useful booklet for others to use.

        謝謝  alan lee.  oh! I live in Vancouer not USA.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 16, 2016, 01:31:31 AM
VER 2.4f is completed and ready for download.

New content added - and some fine tuning.

...

NOTICE TO IGKT members:

It is my intention to lock this paper down and to start charging a fee for use.
IGKT members who have made a meaningful contribution will receive free copies.

VER 2.4f has reached a stage where it is of reasonable quality with content that is acceptable. Some additional work remains - but I am satisfied that the paper has progressed to a much higher level than earlier versions in 2013. Producing this paper has consumed many hours and taxed much of my resources.

I have not set a lock down date as yet - but, it will be very soon.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on February 16, 2016, 10:37:53 AM
Hi Mark,
maybe it could be useful to include a description of a "well tied" (standard) Bowline, for instance, how long (rope diameter) should be the whole collar (the bight coming out from the nipping loop)? 3 - 7?

ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 18, 2016, 08:40:04 PM
Here is one that may generate some interest... #1080
(http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20473;image)
The question is: Does it have 1 nipping loop or 2 nipping loops?
I like this --to my viewing-- enlarged image,
for the sake of some commentary.

Tie this in a reeving-the-tail method (not TIB way)
up to the point where the tail is returned in through
the central nipping loop the 2nd time,
AND THEN
take the end around behind the left-side twin
eye legs --as done, so far-- BUT ALSO back
behind the right-side ("ongoing") eye legs,
AND THEN
tuck the tail down into the nipping loop
between the collar legs and under itself.
Hauling the tail tight should gain security,
BUT WITH LARGER EYE than maybe one might
normally want/use for a climber's tie-in (as
you need enough eye to be pulled in by this
tightened tail wrap, and then to be able to
open for whatever is tied to by the eye).

IMO, this finish makes more sense than the
promoted just-like-bowline_on_a_bight finish
--which, yeah, gives the tail more turns that should
impede loosening/ravelling a bit, but really aren't
the best engineered as a finishing movement,
unlike what I've just verbally sketched.
(And which sketch results also in a TIB knot,
although there are some further adjustments
that destroy this feature, but which might be
favored where the TIB aspect is irrelevant.)

Otherwise, and further, we should note that the particular
version/loading of this knot is one of two possible; and
there is some issue of how exactly to orient the eye legs
as they come from the nub --a problematic thing.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 26, 2016, 01:17:14 PM
VER 2.4g is ready for download.

A major re-write of the Myrtle section at pages 30-31.

Some new images added and some older images replaced and/or enhanced.

Several amendments / grammar / edits made to several pages.

Removed the 'barbie shoe' from the mirrored Bowline.

...

I also need clarification on the images at pages:
[ ] page 40 (figure 8 )
[ ] page 49 (figure 24 )

I am confused as to who discovered what and when and to what extent Xarax was involved...?????

...

I think I am drawing closer to the light at the end of the verrrrrrry lonnnng tunnel.

I welcome any constructive criticism...

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: zoranz on February 26, 2016, 02:48:04 PM
Hi Mark,

i didn't have time to analise all; but for now have one sugestion. I should like to see conv. view of Lee's Zep X Bwl in mirrored view. See attachment!

Best regards (to all)
ZZ
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 27, 2016, 10:13:51 AM
VER 2.4g (27 Feb 2016)

Some last minute additions/amendments to the following pages:
[ ] pages 30-31
[ ] page 32

Redefined the characteristic of a Myrtle is that each leg of the bight enters the nipping loop from opposite directions.
NOTE: Although #1033 (Carrick loop) presents difficulty since it also has each leg of the bight entering the nipping loop from opposite directions - but, the collar structure is different. The collar of a Myrtle encapsulates both the SPart and the ongoing eye leg. In #1033, the collar does not envelope/encapsulate the ongoing eye leg. I have to work through these issues to further refine and tidy up loose ends...

Also added another image on page 32 to assist with understanding the structure of an Anti-Bowline (if thats the moniker that is accepted...). Stating that the collar forms around the ongoing eye leg rather than the SPart (and also a reference to the direction of the returning eye leg as it enters the nipping loop).

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: zoranz on February 27, 2016, 05:34:53 PM
Hi,

I probably was not enough clear. (It is obvious that a knot by operation with mirror can be transformed from R-handed to L-handed and vice versa.) But I want to put accent on the thing - that Fig.24a and Fig. 24b show 2 knots which are 2 different knots (1st is R-handed, 2nd is L-handed.) Through the article there is analog approach where left and right placed pictures show the SAME knot (with front and back view, or rear, detail, conventional, ... - or whichever name you prefer; term is not important for this remark). Fact that the knot is only the one is outlined with a thin curve with arrow.
Now back on Fig.24.: a & b are two distinct (similar yes, but one is Left-handed, other is Right-handed. In that sense 24b has to be mirrored oriented to show the same knot (with view from opposite side!) I'll make new scheme for illustration.

Regards,
ZZ
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 28, 2016, 04:36:14 AM
Thanks zoranz - all fixed I hope!

VER 2.4h (28 Feb 2016) is ready for download.

Link: http://www.paci.com.au/knots.php

Some further amendments have been made.
You will now see copyright warnings on each page.

Added note that contributors are not legally liable for any content or its use thereof. Also added wording that the content and theories presented do not necessarily reflect the views of the contributors unless expressly stated as such.

[ ] added info to page 13 (para 1)...Derek Smith only requires one end of the 'nipping loop' to be loaded (SPart)
[ ] added image to page 24 (test method for investigating effect of increasing the radius of the nipping loop)
[ ] fixed image 24a at page 49

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on February 28, 2016, 11:10:53 AM

Hi Mark,
I'm not able to test anything, but (as I've said already here
http://igkt.net/sm/index.php?topic=4480.msg38319#msg38319 )
I insist the (wrong) Myrtle in the linked picture is unstable, even if the
 the 'returning eye leg' enters the nipping loop from the SPart side!
http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20457;image

--
In the analysis of the standard bowline, what about adding a lateral view of the bowline
to see the torsion of the nipping loop?

--
Ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: zoranz on February 28, 2016, 12:31:43 PM
Thanks zoranz - all fixed I hope!
Now: Fig.24 = OK :)
ZZ
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on February 29, 2016, 07:26:43 AM
Quote
Hi Mark,
I'm not able to test anything, but (as I've said already here
http://igkt.net/sm/index.php?topic=4480.msg38319#msg38319 )
I insist the (wrong) Myrtle in the linked picture is unstable, even if the
 the 'returning eye leg' enters the nipping loop from the SPart side!
http://igkt.net/sm/index.php?action=dlattach;topic=4480.0;attach=20457;image

--
In the analysis of the standard bowline, what about adding a lateral view of the bowline
to see the torsion of the nipping loop?

--
Ciao,
s.

I'll have a look at this tonight... I have to admit that the whole section on the so-called 'Myrtle' is giving me a headache.
I'll try to capture some more photos (and lateral view).
This would probably mean adding yet another page to the Myrtle section.
I'm struggling with finding a robust definition - particularly in the context of #1033 Carrick loop (ie each leg of the bight enters the nipping loop from opposite directions).

...

zoranz, are there are any figures/images/diagrams that are incorrect? My eyes are starting to bleed...!

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on February 29, 2016, 08:40:17 AM
Hi Mark,

I'll have a look at this tonight... I have to admit that the whole section on the so-called 'Myrtle' is giving me a headache.

It seems like the boobash-headache! :)

Quote
I'll try to capture some more photos (and lateral view).
This would probably mean adding yet another page to the Myrtle section.
I was referring to the standard bowline about the lateral view!
(Does the Myrtle deserve more space?)

Quote
I'm struggling with finding a robust definition - particularly in the context of #1033 Carrick loop (ie each leg of the bight enters the nipping loop from opposite directions).

You show the right Myrtle in the paper, you could say that the most stable Myrtle (the right Myrtle) has legs entering the nipping loop from opposite directions and  "turns" (nipping loop and the other one) with opposite chirality.
The instability of the wrong Myrtle (legs entering from opposite directions and turns with same chirality) is better noticed if the angle between the eye legs is more than 45 degree (for instance think the (wrong) Myrtle tied around a tree). In that case the tail can get out of the nipping loop.
About the "Myrtle" having legs entering from the same direction, I'm not able to evaluate the stability, even if I prefer that with opposite chirality.
Maybe we should consider the "Double Myrtle" (Round Turn Myrtle = Myrtle structure with ABoK 1013 nipping loop))!!!  ;)  :o

Ciao,
s.

p.s.  p. 3  missing a ")" after "Scott Safier (USA"
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on February 29, 2016, 11:01:29 PM
VER 2.4h (28 Feb 2016) is ready for download.

Link: http://www.paci.com.au/knots.php
Thank you (not needed to access, so available here   :D  )  !

Some quick comments on remarks visible in this thread.
1) "each leg" (or "both legs") enter from opposite sides
is a poor expression --teasing one to remark "could only
one leg do so?"!
1.b) More substantively, that is WRONG (and otherwise
would be an ambiguous, not defining/restrictive) :
the returning eye leg enters on the S.Part side, and so
too does the tail, in completing the loop.
.:. What should be said instead is that the returning
eye leg makes a loop vice a bight (and, yes, this implies
that one doesn't call it a "bight" !), which distinction is
precisely that evidenced by the tail NOT going in the
opposite way vis-a-vis the plane of the nipping loop
but going the SAME way; that for a bight/collar would
go back out the way it came in --i.e., in reverse/opposite
direction.
(The viewing community doesn't see this and remark to Mark ... ?!?!?!?!!!)

2. STILL having confusion about "anti-bowline"??!
Egadz, it is quite simple (at least in stating) : the returning eye
leg enters the nipping loop from the side opposite to the
S.Part's side (where "side" is in reference to the plane of
the loop and this plane magically *thickens* at the loop's
crossing point to give a S.Part side & ongoing eye leg side
--a distinction, recall, made by me and reiterated by X.
in our advocating which side/face of the bowline should
be presented --which is the side opposite to what history
has give to us (and, IMO, which has led many to have
trouble comprehending the knot --evidence of which
incomprehension is abundant, whatever its cause).

So, re p.30 of 49 boxed assertion of a mistaken distinction,
there is no regard for what the entering part does AFTER,
only how it enters --it might loop as seen in the Myrtle
or collar as seen in the bowline (both knots are NOT
"anti-bowlines".  (Trickier cases can come when this
defining entry is made somewhere *later*, the initial
eye-leg return doing something other than going
through the nipping loop.)

You should perhaps best set this distinction by:
showing both --as you do-- images of the JUST-ENTERED
states of bwl/anti-,
AND THEN
complete both a bwl & Myrtle,
and in contrast also an Eskimo Bwl & "Bollard loop"
--which latter will differ from the Myrtle by having
the tail tuck out towards the eye and hence
achieve opp. chirality also. (AND IF you want to include
the benefit of a fine eye knot so formed, make one
further wrap with the tail and dub that "double"
for a "double bollard loop" (which double-wrap gives
much better gripping/nipping hold on the central
nipping loop's parts).  That's a good knot to have!

(The clearest cases have the bights/collars; the loops
within loops are a trick to decipher, as we've seen!  But
having both presents a fuller set of knots, and helps
the latter tricky cases by having the easy ones nearby.)

DO NOT CALL IT "UNSTABLE MYRTLE" :: it is NOT NOT NOT
a(ny sort of) Myrtle!  (And, it is not all so bad, esp. if the
tail is secured to the S.Part as some have done; one can
"double" this knot, too, and improve stability.  You are
right about dubious stability, but I think it's better than
the wrong-way (same-handedness loop) Myrtle
(though in current fiddling rope of 1/2"? laid flat-film PP,
even that one was holding --and thus confusing me!).

ACK, p.31 is exactly what I'm talking about above ::
2.c the left knot is QUITE STABLE, and in fact holds better
than the bowline in some cases --"jams" sort of--
and presumably was so chosen by some commercial fisher
whose handiwork I later salvaged --actually, it was the less
stable version that I have (fairly unworn 5/16"? marine
kernmantle, kite-strings-like yarns).
.:.  THOSE STRUCTURES ARE (a) NOT "MYRTLES", (B) ANTI-BWLS,
(c) STABLE & MAYBE-STABLE, RESP., AND ...
you'll do best if you consistently refer to how the tail
enters the nipping loop RE S.Part
--i.e., don't say
"as eye leg" for one and "as S.Part" for other,
but "same as"/"opp. side to/as" for consistent reference
item, the S.Part (I think this should be best, the common
reference part).

Further re these images :: note that you've changed too many
things between them --i.p., the loop of the tail--; rather, just
show same silhouette in right side as in left, but there
with tail crossing behind itself rather than in front
--and an arrow to connect these two side-by-side diff.s of
course focuses attention to this ONE point (and that's all
there is).  As it stands, one goes back'n'forth trying to see
what's different, and there are specious differences because
you've rotated/changed the tail's loop in right image vs. left.

3) "Dan Lehman argues that this structure is deserving of the
name 'anti-bowline'." is wrong-headed in import :: rather, I
(or w/o personal attribution, *it is said/advocated* (and much
it was done for a quick, named distinction) that ...
in the sense of "cyclone" & "anti-cyclone" which terms
denote opposite directions
.  THAT will help people deal with
the potentially wrong sense of "anti-" of "against".
(And, it shows that "bowline" has different *levels* of meaning,
both as an overall denotation for knots-with-nipping_loop (me,
at least), and as one *half* of such knots where the tail
enters ... and the other half has the tail entering opposite.)


THE DIFFICULTIES IN DEFINITION, or we might more sympathetically
state "in applying/realizing such definitions" can be shown both in
the Eskimo bowline and maybe more strongly in the carrick loop
#1033 which you wrongly label "1439" of the end-2-ender,
showing the non-bowline (IMO) tightly set knot vs the
softer set expressly to comply w/preserving a "nipping loop"
knot --a diff. that can be illustrated but not well realized
in #1010 by setting it hard via the tail --loading will see the
S.Part pull back sufficient collar to dispel the crossing-knot
appearance of the tightly set ("SS369'd") knot.


4) Fig.s 3xx should follow the YoBowl and not precede it,
and should thus come with the remarks that not only is
it simpler (oh. vs 8 tail finish) and ALSO TIB (nevermind
"X points out" what was said prior and obvious enough
--funny you don't remark about TIB for YoBowl?!).
Also funny that you don't carry the warning of mis-positioned
parts of YoBowl to Alan's variation, where it is a risk, too.


Quote
[ ] added info to page 13 (para 1)...Derek Smith only requires one end of the 'nipping loop' to be loaded (SPart)
I'll not go further here but to note that you're grasping
for definite definitions which haven't been forthcoming;
they are a matter of opinion, experience or lack of, and
aims for classification (purpose).  For me, at this stage,
it's the nipping loop, and includes things that are not
PET (which have the mid-fype geometry of the fig.8
e.g.).  BUT, if one has a purpose to exclude such ... ,
then that can be put into definitions, as you have.

But we all assume the basis that we're talking about
eye knots so much that I'd not even list this as one
of the defining aspects --or as #1 sine qua non, not #3 (!).


--dl*
====

ps : <gasp> This is what happens w/me & knotty stuff :
the "quick" loses out to further thinking & looking and ... ;
go to record 1 fiddled knot and instead of doing so end up
with that same 1 and maybe 2 others standing in need!
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on March 01, 2016, 09:31:25 AM
Some quick comments on remarks visible in this thread.

Thank you, Dan_Lehman!

I read my previous post and I notice that I said what I meant very very very badly!  :-[
 :(

you could say that the most stable Myrtle (the right Myrtle) has legs entering the nipping loop from opposite directions and  "turns" (nipping loop and the other one) with opposite chirality.

The legs (I was referring to) are the returning eye leg and the ongoing eye leg (even if the ongoing eye leg doesn't enter the nipping loop!?!?), that is to say (I meant (I would have meant)),
 the returning eye leg enters the nipping loop from the side opposite to the ongoing eye leg (= the returning eye leg enters the nipping loop on the SPart side).

Thanks,

Ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on March 07, 2016, 08:52:12 AM
From Dan Lehman:
Quote
(The viewing community doesn't see this and remark to Mark ... ?!?!?!?!!!)

Probably the reason is the same as mine - staring at a computer screen for way too long and going loopy from looking at Z and S twist loops.

I am fixing this error...

Definition of a Myrtle:
A defining characteristic of a Myrtle is that each leg of the bight enters the nipping loop from the same side - forming a loop. The legs of the bight have a crossing point and do not lie in parallel as with a standard #1010 Bowline.

In a standard #1010 Bowline, each leg of the bight enters the nipping loop from opposite directions. The legs of the bight lie in parallel.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on March 08, 2016, 09:11:40 AM
This is to advise that VER 2.5 (08 March 2016) is ready for download.

Link: http://www.paci.com.au/knots.php

Document is now 50 pages in length.
Another re-write of the section on Myrtles - significant changes made.
Added a new page comparing Anti-Bowline to Myrtle.
Several amendments and new additions have been made - in particular arrows showing direction each leg of the bight takes as it enters the nipping loop.
Added new content on page 11 about reverse engineering a knot by untying it (without access to either end) to determine if it is TIB.
Added new content on page 13.
Added content on page 14 showing direction each leg of the bight relative to the nipping loop.
Added another knot on page 17.
New content on page 24 - showing test method to determine effect of 3 rope diameters inside nipping loop.
Added direction arrows on page 28 (#1033 Carrick loop).
Numerous changes and amendments on pages 30+31 (added new term of 'Anti-Myrtle').
Page 33 is new content.
Call-out text box added to page 34.

I welcome comments and constructive criticism.

I'll keep the document open and free for a little while longer...

EDITED:

I need feedback and clarification on the following:
[ ] page 14 - reference to the bight having 2 legs (with each leg entering the nipping loop from opposite directions in a standard #1010 Bowline) - is the use of the term 'legs' and 'legs of the bight appropriate'?
[ ] page 28 - another reference to 'each leg of the bight'... I had advanced the concept that the bight has 2 'legs' - to aid in describing the structure - is the use of the term 'legs' and 'legs of the bight appropriate'?
[ ] page 30 - need to redefine what a 'Myrtle' is (yet again) - remove reference to a 'bight' since there is no actual 'bight'. It is a loop.
[ ] page 31 - I advanced the concept of an 'Anti Myrtle' to distinguish from 'Myrtle' - hopefully this is in accord with 'Anti Bowline' and that the use of the term Anti Myrtle is appropriate?
[ ] page 33 - Myrtle photo at bottom right - I should perhaps redefine that Myrtle don't actually have a 'bight' component - they only have a collar (there is no bight - it is in fact another 'loop')
[ ] page 41 - figure 8a - I still dont have accurate information about its discovery and who was involved - including the name originally given to it
[ ] page 50 - figure 24a and 24b - I still dont have accurate information about its discovery and who was involved (I know Alan Lee was involved but i dont have dates and to what extent Xarax was involved).

[ ] I also want to include some greater details about 'TIB' - and why it is a valuable property of a Bowline (compared to those that aren't TIB).
[ ] I also would like some TIB tying sequences for a few Bowline structures.  I had advanced the concept of 'reverse engineering' a knot by trying to untie it without access to either end (which I think was also posited by Harry Asher??).


Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on March 16, 2016, 08:33:23 AM
VER 2.5a (16 March 2016) is ready for download!

Note that the paper is still free-for-use to IGKT members. Once I lock down the paper - only those IGKT members who have made a meaningful contribution will continue to get free access.

Critical review and feedback is welcomed.

Significant amendments have been made.

I would like to thank Dan Lehman and in particular Constant Xarax for their precise, targeted critique.

It send me back to the drawing board in some areas... (with my tail between my legs).

Both Dan and Xarax hinted at the trouble I was running into with loops and legs (making clear cut explanations of which leg is going in what direction muddled).

Xarax pointed out that I was looking at the 'bight' in the wrong way. I can now see with clarity his viewpoint and it makes sense.

In a nutshell, the 'bight' is actually a composite of 5 individual segments. When referring to the 'bight' - this is simply a holistic view on a macro scale.
On a micro scale - the bight structure consists of:
[ ] the collar
[ ] the legs of the collar (2 legs)
[ ] the returning eye leg
[ ] the tail

And this was what I needed to enable the overhaul the whole section on Myrtles (again) along with several other key interpretations in other pages.

In a nutshell, the Myrtle can now be defined as:
1. Both legs of the collar lie on opposite sides of nipping loop - exiting and then re-entering the nipping loop from the opposite side.
2. The consequence of this is that the legs of the collar form a loop - they do not lie along a parallel pathway.

In contrast; in a standard #1010 Bowline, both legs of the collar lie on the same side of the nipping loop. The legs exit from and then re-enter the nipping loop from the same side.

Furthermore, the legs of the collar can be distinguished:
[ ] loaded leg
[ ] unloaded leg

The nipping loop itself marks the demarcation point from where the returning eye leg enters the nipping loop and then exits as the loaded leg of the collar.

The tail segment begins from where it exits from the nipping loop.


...

Anyhow, I think that light at the end of the very loooonnnnnng tunnel is growing much brighter now :)

Mark

EDIT: A couple of last minute typos were corrected and the contents page was corrected...if you download the document after this edit notice all will be fine!
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on March 17, 2016, 06:39:29 AM
VER 2.5b (17 March 2016) is ready for download!

Note that the paper is still free-for-use to IGKT members. Once I lock down the paper - only those IGKT members who have made a meaningful contribution will continue to get free access. Permission to freely download for personal use is authorized!

Critical review and feedback is welcomed.

Change log:
[ ] page 6: small typos corrected (also removed white arrows)
[ ] page 14: clarified legs of the collar and removed white arrows
[ ] page 15: typo corrected (sheepshank has 2 nipping loops)
[ ] page 17: reference to 'double helix' deleted to avoid confusion with DNA 'double helix' structure
[ ] page 19: New page added! Bowlines based on a Girth hitch nipping loop
[ ] page 30: Lee Zep Bowline (removed 'X' from descriptor) - also added May 2012 discovery date
[ ] page 32: added callouts to further enhance interpretation of structures...also corrected error in reference to legs of the collar
[ ] page 33: corrected white arrows - to enhance interpretation
[ ] page 34: error corrected
[ ] page 40: added TIB symbol to Yosemite Bowline
[ ] page 42: added TIB symbol to figure 8b - also added name of knot (Lees Link Bowline reference to Nov 2013)...still unclear about exact discovery date and who tied it!
[ ] page 51: changed name to... 'Lee Zep Bowline (removed X). Added discovery date May 2012.

Am close to exhausting all my available time to this project. So last round of comments are welcomed...

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on March 18, 2016, 10:02:11 AM
VER 2.5b (17 March 2016) is ready for download!

Hi Mark,

p.19, ln.2 "(aka 'lark's head')"

ciao and thanks,
s.
p.s.
I haven't changed my mind about the wrong Myrtle!
You haven't changed your mind about the wrong Myrtle!
 :o  :D

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on March 18, 2016, 01:57:51 PM
VER 2.5c (18 March 2016) is ready for download!

Final round of comments please... as i am nearly brain dead and the life force has practically left my body  :-\

Dan Lehman has been ominously quiet - which terrifies me. Normally he barks at me like a rabid dog sending me in retreat with my tail between my legs  :o

Xarax has extensively counseled me....the 'legs of the collar' had unsatisfactory names.

I have renamed them as:
1) entry leg; and
2) exiting leg.

Hopefully this is acceptable now?

I have also added a whole new page (page 13) - depicting the 4 orientations of the 'Anti-Bowline' (#1034 1/2).

Note: I have also depicted 4 orientations of the standard #1010 Bowline.

Some may not approve of this...but I have given my rationale on page 13. Basically, I think Ashley should not have named #1034 1/2 as a 'left-hand' Bowline. This is just confusing the concept of Z twist and  S twist nipping loops. He didn't name it a 'Left hand' Bowline on account of the 'handedness' of the nipping loop - and it is my view that the concept of handedness (ie Z twist Versus S twist) of the nipping loop was not something he considered.

It would seem that the first time this was brought to light in a mainstream knot book was by Dr Harry Asher (The Alternative Knot Book). Asher used the term 'sense' - rather than Z twist or S twist or 'chirality'. I have taken matters another step forward...

...

knotsaver:

I thought I did acknowledge your position on this matter?
Please refer to page 32 (bottom left). I mentioned that a Myrtle can be further enhanced if both loops are of opposite chirality.
On page 33, I did mention that the handedness of the loops is not the principal factor (at bottom right). I do believe that the direction from which the returning eye leg enters the nipping loop to be a principal factor.

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on March 18, 2016, 05:02:11 PM
VER 2.5c (18 March 2016) is ready for download!

I have also added a hole new page (page 13) - depicting the 4 orientations of the 'Anti-Bowline'
Note: I have also depicted 4 orientations of the standard #1010 Bowline.

Great! very clear! I like it!
(you haven't introduced the "Anti Bowline" yet, you could refer the reader to the right page)

I think Ashley should not have named #1034 1/2 as a 'left-hand' Bowline. This is just confusing
...
I agree with you,(http://igkt.net/sm/index.php?topic=5490.msg37331#msg37331)
but we have to notice that the ropes we use today are not the ropes used by Ashley, if we tie a #1010 Bowline with a right-handed (twisted) rope (see ABoK #106), the collar follows the torsion of the rope (in a right-handed fashion), but if we tie a #1034 1/2 Bowline with the same right-handed rope, the collar goes against the torsion of the rope (in a left-handed fashion), maybe for that Ashley named the #1034 1/2 a left-hand Bowline (maybe!?)...

knotsaver:
...
I thought I did acknowledge your position on this matter?
I do believe that the direction from which the returning eye leg enters the nipping loop to be a principal factor.
I see, Mark, but I don't believe that! :)
(for that I've noticed that I haven't changed my mind and you haven't changed your mind...and I don't know if we are able to do that :) )
I say it again: I'm not able to demonstrate what I say  :-[ and I think it depends on the rope used too, but my personal classification about the stability of Myrtle-AntiMyrtle is:
1. Myrtle (opposite handedness loops)
2. Anti Myrtle (opposite handedness loops)
3. (?) wrong Myrtle (same handedness loops)
4. (?) wrong Anti Myrtle (same handedness loops)

I think that  3. and 4. are unstable! 2. is better than 3. (Dan Lehman said it too see http://igkt.net/sm/index.php?topic=4480.msg38446#msg38446) so to my mind the opposite handedness is a principal factor. Surely the stability is improved if we tie double nipping loops!
---
Last note: why do you talk about the Lee Zep Bowline in two different times (p.31 and p.52) (and the first time before you talk about the Myrtle)?
(in the index you call it Lee Zep Bowline (p.31) and Alan Lee Zep Bowline (p.52)).

Hope this helps.
ciao and thanks,
Saverio.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on March 19, 2016, 02:52:56 AM
VER 2.5d (19 March 2016) is ready for download!

Further changes to the section on Myrtles (yet again...)

knotsaver - I hope that you will find my improvements to the section on Myrtles to be satisfactory?

After this, I never want to look at another 'Myrtle' ever again  :o

Xarax pointed out that my grammar was incorrect (again). I am ashamed to be born in an English speaking nation and find that someone born in Greece points out my poor English! Normally, when Xarax barks at me - its all Greek to me.
Anyhow, with regard to the collar and its 2 legs:
[ ] entry leg
[ ] exit leg (instead of 'exiting' leg, otherwise entry leg would need to be 'entering' leg).

At least he approves of my use of the concept of 'entry' and 'exit' legs...
...

Knotsaver, with regard to your post at this link: http://igkt.net/sm/index.php?topic=5490.msg37331#msg37331   
I agree with your interpretation of the chirality of the nipping loops. However, it is very unfortunate that Ashley chose to use the name 'Left hand Bowline' for #1034 1/2. Your hypothesis re the 'lay' of the rope influencing his decision to use the term 'left-hand' is interesting and perhaps could be further investigated?


Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on March 19, 2016, 05:49:25 PM
knotsaver - I hope that you will find my improvements to the section on Myrtles to be satisfactory?

Mark, if you agree with me that the Myrtle (opposite handedness loops) is better (is more stable) than the "wrong" Myrtle (same handedness loops) in the Note at p.32 (bottom left) (btw the second bracket in the Note is out of position)  you could say that if both loops are of same handedness the stability gets worse...
IMO the important message is: if you use the Myrtle (opposite handedness loops) OK, but if you use "Myrtle (Anti-Myrtle) variants" be cautious!
(However you have to find the section to be satisfactory.)

After this, I never want to look at another 'Myrtle' ever again  :o

 :D
me too!  :D

However, it is very unfortunate that Ashley chose to use the name 'Left hand Bowline' for #1034 1/2.

I agree with you!

Ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on March 22, 2016, 05:59:52 AM
VER 2.5e (22March 2016) is ready for download!

Amended and enhanced page 32 (Myrtles)....again!

knotsaver, your comments would be appreciated. I hope the amendments meet with your approval?

Mark G

Edit: typo corrected...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on March 22, 2016, 05:31:32 PM
VER 2.5d (19 March 2016) is ready for download!
...
At least he approves of my use of the concept of 'entry' and 'exit' legs...
...
Which presumes there being some *movement*.  Tell me,
how are the legs to be named for the bowline on a bight?!
--two "entering" and nOne departs?!

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on March 22, 2016, 06:13:40 PM
VER 2.5e (22March 2016) is ready for download!

Amended and enhanced page 32 (Myrtles)....again!

knotsaver, your comments would be appreciated. I hope the amendments meet with your approval?


Mark, I feel honoured :)

I think we can stop talking about the Myrtle! ;)
(BTW it seems that a "wrong" Myrtle tied with a stiff rope is more stable than the one tied with a soft rope...)
Only a question: What is the meaning of the exclamation mark in the (figures of the) paper?

---
typo:
p. 39
name boxes: ABoK #1034 1/2 (Detail view) and ABoK #1034.5 in the other box
p.43
name boxes: missing the name of Lees Link Bowline
p.51 no name boxes; Eskimo names are not the same in the detail and conventional view
p.52 no name boxes
---

Ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on March 23, 2016, 07:02:08 AM
knotsaver:
I have already made the amendments you identified (thanks for pointing them out).

Dan Lehman:
I have created a new temporary PDF file showing the 'anatomy' of #1080 (Bowline on a bight).
Direct download link here: http://www.paci.com.au/downloads_public/knots/Anatomy_1080.pdf

In short, the concept evolved by Xarax is undisturbed by the existence of #1080 (Bowline on a bight). The collar and 2 legs are the same.
It is nevertheless a very good structure for analysis - and it is being included in the latest revision of my paper as a write this post. Some of the terms are my working ideas only - and are not set in stone. The 'entry' and 'exit' legs of the collar still follow the same rules as #1010. Of technical interest is the ongoing eye leg and returning eye leg - since we now have a 'primary' and a 'secondary' eye. I also maintain my position that there is only one nipping loop.

Any interested reader should download the new (#1080) PDF file and comment!

I will delete that file as soon as I have gathered sufficient comment for consideration and follow up action...

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on March 23, 2016, 11:37:17 PM
Any interested reader should download the new (#1080) PDF file and comment!

Mark,
my question is: is this knot (the one you show) a secure knot?
I don't think so! if we only load the secondary eye, the primary eye can "disappear"...or (much worse) the secondary can slip and become untied...
Ashley in #1080 says: "It is the knot generally used at sea for lowering an injured man from aloft. One leg is put through each loop and if conscious the man holds the double standing part in hand...." (italic-bold is mine), so ABoK #1080 is not tied with a short tail! but if Ashley had to tie #1080 near the end of a rope, he tied #1075! (Bowline on the bight and Bowline)
 :-\

Ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on March 24, 2016, 12:26:06 AM
knotsaver - thanks for your question.

I would like to emphasize that virtually all of the Bowlines presented in my paper are loosely tied. Furthermore, the inclusion of a particular knot does not warrant that it is 'safe' for use in any particular application. The Bowline on a bight (#1080) is presented on the basis of how the components constituting its structure relate to the standard #1010 Bowline.

One could argue that many of the Bowlines presented have certain inherent risks - I cant account for (and document) each and every conceivable risk.

The knots are presentation for theoretical analysis.

I will check and then re-check my paper to ensure that there is a clear and obvious legal warning - and if not, I will add clear and unambiguous legal warnings.

...

By the way, your comments are correct and I agree with them. In practice, if using #1080 for human life support applications, it would be wise to secure the tail in an appropriate way (eg by way of a strangled double overhand knot tied around the SPart). And, both eyes should be loaded as a pair simultaneously - and not used separately.

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on March 24, 2016, 12:08:42 PM
I would like to emphasize that virtually all of the Bowlines presented in my paper are loosely tied. Furthermore, the inclusion of a particular knot does not warrant that it is 'safe' for use in any particular application.

OK, OK!

The Bowline on a bight (#1080) is presented on the basis of how the components constituting its structure relate to the standard #1010 Bowline.

I don't know if it has already been said, but we can say that #1080 (tied near the end of a rope) is a standard #1010 with Yosemite eye-and-finish (naming the secondary eye a Yosemite eye !?) :)

I've always thought about the Bowline on a bight as a whole, but it is better to analyse its parts!
Thanks.
Ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on March 29, 2016, 04:16:25 PM
VER 2.5f (29 March 2016) is ready for download!

This is most likely the final version...unless there are any glaring technical errors - in which case I will fix them.

Added a new page (based on an idea from Dan Lehman) - page 17

Several amendments have been made based on technical advice from Dan Lehman.

I have decided to keep the name 'Anti-Myrtle' for now...as it still fits the general theory in my view.
Also decided to keep the page on the 'capstan effect' - despite opposition from some. My reasons are that a reliable and reproducible test method needs to be devised which can either confirm or deny its existence. In fairness to Xarax, the page should stay. In any case, there needs to be some discussion on the capstan effect because it is a point of interest.

PASSWORD TEST
You will note that I have password protected the paper again - and the 'permissions' password is quite long, random and contains lots of non alpha-numeric keys. Not sure if it can be broken/hacked. Please message me if you are able to crack the permissions password so I can work to improve the security.

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on April 01, 2016, 02:25:58 AM
VER 2.5f (31 March 2016) is ready for download!

Please note that I have now locked down the document.

It remains to be seen as to how hard it will be to crack the document and break the encryption...
Link: http://www.paci.com.au/knots.php

...

I am a man of my word and I said that any IGKT member who has made a meaningful contribution will be granted free access.
If you are a current IGKT member - I will grant free access for the next week or so...but after that, it will only be free to those members who actually made an effort to contribute.
NOTE: There was a small minority who declined to assist in any way - without even bothering to give any evidence to support their position re Bowlines. I went out-of-my-way to invite them to contribute so that their viewpoint could be heard. Those individuals will not be granted any free access.

Please PM (message me) and I will provide the password.

I would like to thank all of you who made this project possible :)   You know who you are!

,,,

I can now move on to my next project which is 'Offset joining knots' (oh dear....what have I done). I will be looking for contributors to this project...

Mark Gommers
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 01, 2016, 06:14:53 PM
VER 2.5f (29 March 2016) is ready for download!

I have decided to keep the name 'Anti-Myrtle' for now
...as it still fits the general theory in my view.
Introducing this name ("anti-b...") is increasingly causing me
regrets; this abuse of it only aggravates that.  The "general
theory" isn't a theory of mine, who coined the term :: mine
is simply put vis-a-vis the (IMO) fundamental element of all
**bowlines**, the "nipping turn"; so, re that, the issue is
one of from which side the tail is tucked through.  In the
(#1010) bowline it is tucked from the side of the loop
on which the SPart lies at the crossing/closing point of the
loop, also done for the myrtle, and from the opposite side for
the "bollard loop" aka "Swedish bowline" (names attributed to the
knot in one Knotting Matters article some several (8?) years
ago.
(Though, alas, I can see that there can be a confounding
aspect of *direction* of the tuck --e.g., that one might tuck
from some prior wrapping/knotting going SPart-side in and
down to collar eye legs, which would put the tucked
strand in identical orientation to a tuck made in the opposite
direction, which of course would be from the opposite side!)

In some simple cases (knots), one can see the from-legs-side
tuck having to make a greater effort to resist the nipping loop
from changing into an increasingly open helix, whereas for
the opposite tucking (SPart side in), there is often greater
hope to effect a sort of *half-hitch* vs. helical orientation
to the nipping loop --though the many capsized bowlines
I've observed in the wild testify to the vulnerability of even
this basic knot *to get helical*.

.:.  "anti-" already connotes too harsh and wrong notions.
On balance, I favor its complete removal, lest it sully the already
unclear waters with seriously misguided notions.
Given my more recent thoughts/realizations about the lack of
a sure, practical-in-knot-behavior distinction based on the
tucking, it might all be "back to the drawing board".

(Perhaps we give up hope for some sort of objective discriminator
--or even of imputing some divide(!)-- for just a more subjective
general indication of probable tendencies re becoming helical?)

Quote
Also decided to keep the page on the 'capstan effect' - despite opposition from some. My reasons are that a reliable and reproducible test method needs to be devised which can either confirm or deny its existence. In fairness to Xarax, the page should stay. In any case, there needs to be some discussion on the capstan effect because it is a point of interest.
I fail to see this as, at best, putting the cart before the horse :
there is currently no confirmation of existence, but you want
to promulgate the --one person's!?!-- notion and hope that
something comes along, maybe?!  In fairness to US, X. should
have demonstrated there to be other than conjecture on this
point; some of us, in fairness to the argument, have sought
this and come up empty.
.:.  There is friction around variously per configuration and
material and force, and ... I don't see this named effect worth
the positing in this case for the particular aspect.  And yet you
give it such a beyond-mere-mention treatment.  (One might
also note simply the bending moment (sharpness) of the
"proper collar" along with any musing about friction.)


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 01, 2016, 06:42:34 PM
(Though, alas, I can see that there can be a confounding
aspect of *direction* of the tuck --e.g., that one might tuck
from some prior wrapping/knotting going SPart-side in and
down to collar eye legs, which would put the tucked
strand in identical orientation to a tuck made in the opposite
direction, which of course would be from the opposite side!)

In some simple cases (knots), one can see the from-legs-side
tuck having to make a greater effort to resist the nipping loop
from changing into an increasingly open helix, whereas for
the opposite tucking (SPart side in), there is often greater
hope to effect a sort of *half-hitch* vs. helical orientation
to the nipping loop --though the many capsized bowlines
I've observed in the wild testify to the vulnerability of even
this basic knot *to get helical*.
//
--dl*
====
Consider the simple case between my "hilarious bowline" and
a variant of it (which might get a name suggesting similarity).

The former :: form the basic structure of the SPart turning the
loop and forming the eye;
bring the eye leg up alongside/parallel to its departure
(when then "ongoing") from the loop, lying on away side
from nipping loop (not crossing it) --and so, not yet tucking it
through the turNip);
take this working end over-&-around the SPart
(well, the step above will have it already lying "over");
bring it back over the eye legs and then
tuck a bight from the SPart-side through the nipping turn.
.:.  This tuck conforms to the "non-anti" aspect.
To "go helical" will require the turNip to bend the trucked
bight strands ... --and vulnerability depends on how firm
the material is and how *half-hitched* one dressed the
nipping turn when completing the tuck/knot.  In my
stress tests, it looks pretty decent --and thoughts of use
are for (a) strength tests because of the SPart's effected
decreasing radius curvature, (b) having a quickly tied
in-the-bight knot for some immediate need.

[where '-----P'  is SPart up, making turNip, & ongoing eye leg
   '===' eye bight, both eye legs, out & returning
   go around stem of P
   and then up over eye legs
   and tuck bight up-out-through "P" hole (back-to-front) ]

   ------P   ->  -====P    ->  -=====|P_


The variant --back to the challenge of the overall "bowl/anti-b"
divice-- goes like the above but one tucks a steo sooner,
after turning the working end around the SPart (and, so,
from the non-SPart side of the nipping loop) --tuck a bight--,
BUT THEN --for knot kntegrity--
one pulls the eye (-bight) through the tucked bight, which
collars it, and gives knot integrity.

If nipping loop is in-ASCII  ' (  ) ', we have e.g. in both knots ( / )
and diff. direction only of the slash --from down up or up down,
entering one or other side (and tickling mused distinction)
but same angle in hopes to stabilize/orient loop against becoming
helical.

The general *angle* of the nipped bight parts is the same
for these eye knots.  In the first, the tucked tip is left just
out in the air (as so for that of the sheepshank e.g.),
but in the latter, that tucked bight collars the eye legs.
In both, the angle tries to resist the loop becoming helix.
YMMV on success in this resistance.

But, now, to separate them as, resp., (my terms) in genus
"bowline" & "anti-b." ?!  Noting, surely, that this marking
an academic, technical point :: but why are we making this
point?  --because it often ...   !?  Well, I'm not sure about
defending "often (is associated with <certain behaviors>)".
Yes, in some simple cases,
this distinction presented itself to me.   But it might be as
wanting for much acclaim as "capstan effect".

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on April 02, 2016, 01:17:48 AM
Quote
Introducing this name ("anti-b...") is increasingly causing me
regrets; this abuse of it only aggravates that

Your use of the word 'abuse' is going too far. Nobody is abusing the term.
I considered your use of the term 'anti Bowline' for quite some time (more than a year). I could not devise a better alternative so I agreed in principle with its use.
The attached photos show 'standard' (ie regular) Vs 'anti'.

Anti conjured images in my mind of something being 'opposite' or 'against'. If we consider the direction from which the returning eye leg enters the nipping loop, the use of 'anti' to describe an 'opposite' or 'against' direction would appear to be appropriate.

Quote
"anti-" already connotes too harsh and wrong notions.
On balance, I favor its complete removal, lest it sully the already
unclear waters with seriously misguided notions.

Who is misguided here?

The terms 'cyclone' and 'anti cyclone' are routinely used in my part of the world - which refer to the relative direction of spin/rotation.
Anti is a prefix in common use in the English language.

There is also 'arctic' and 'antarctic'.

And 'Proton' Vs 'Anti Proton'

The direction from which the returning eye leg enters the nipping loop is key to what type of structure you will end up with (in a Bowline).

Dictionary meaning of 'anti' :

prefix
1. against; opposing: anticlerical; antisocial.
2. opposite to: anticlimax; antimere.
3. rival; false: antipope.
4. counteracting, inhibiting, or neutralizing: antifreeze; antihistamine.
5. designating the antiparticle of the particle specified: antineutron.
[from Greek anti]

...

I used the descriptor 'Anti Myrtle' because it distinguished a Myrtle tied with the returning eye leg entering the nipping loop in the standard/normal direction versus entering from the opposite (anti) direction.
It also fit in with the general concept of Bowline Vs Anti Bowline in terms of which direction the returning eye leg enters the nipping loop.
I wanted to be consistent - and the direction of the returning eye leg appeared to be key to this consistency.

/////////////

I would say that your continued use of the term 'turNip' and/or 'nipping turn' is an abuse.
I thought the notional view of a turn Vs a loop had been settled?

Should we describe a 'round-turn-and-2-half-hitches' as 'a round loop-and-2-half-hitches'?

When is a turn a turn and when is a loop a loop?

At some point, we have to stop and agree on terminology - and this is something I have pointed out several times over the past few years. It appears that elements within the IGKT still cannot agree on a standardized knotting terminology.

I would also comment that your 11th hour change of mind with the use of the term 'anti' is a bit late in the day. Why wait until now (at the very last minute) to waive the red flag?
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 03, 2016, 06:00:05 PM
The attached photos show 'standard' (ie regular) Vs 'anti'.
And, in short, they are good to show how my thinking
has lately changed ::  that now I am favoring looking at
the nipped part's angle rather than direction through
the central nipping loop.  !?  --as a reasonable (?)
distinction (rather than merely possible one) for *bowlines*.
That in the one (first-shown) case this angle (readily) makes
the nipping loop orient towards non-helix, crossing-part pressure,
in contrast to the (2nd shown, "anti-") other which invites
helical separation of the loop --though knots of this kind
should be (insofar as they want to be *bowlines*) dressed
and set so as to resist such opening of the loop.

And my verbally sketched hilarious & <similar> bowlines paint
the point well, both having such an angled nipped part,
yet delivering that part from opposite directions --really
op. dir. and not just op. sides!


Quote
Quote
"anti-" already connotes too harsh and wrong notions.
On balance, I favor its complete removal, lest it sully the already
unclear waters with seriously misguided notions.

Who is misguided here?

The terms 'cyclone' and 'anti cyclone' are routinely used in my part of the world - which refer to the relative direction of spin/rotation.
Anti is a prefix in common use in the English language.
Now you're quoting my utterances back to me!  Yes,
this was just the use that brought out my introduction
of the term.  Re "abuse", IMO it is your taking it purely
qua "against" for anything, rather than my intended
pure "opp. side from #1010" focused denotation!
(E.g., suppose that the myrtle had been itself of
the "anti-b." side, like the Eskimo bwl. : yes, by your
thinking the actual M. would then be "anti-M" but
that focuses on the very "original" knot itself irrespective
of how it is oriented; whereas I, who see *bowlines* as
all with a central nipping loop [<--see, I'm redressing
my past sins!], cite it as a violation of the point, which
is "anti-b." is a genus indicator irrespective of there
even being any "non-anti" corresponding knot : the "anti"
refers to a particular side of working-end entry, period.

Quote
I would say that your continued use of the term 'turNip' and/or 'nipping turn' is an abuse.
I thought the notional view of a turn Vs a loop had been settled?

Should we describe a 'round-turn-and-2-half-hitches' as 'a round loop-and-2-half-hitches'?
TOUCHE'!  Ouch, I've been doing this for quite some time.
I'll like to blame another for getting "nipping turn" out into
parlance for my cutesie "turNip" word-fusion,
but, yes, originally and rightly/aptly it is a "nipping loop" about
which we should talk --that, fitting the defined "loop" of many
books (neverminding the overloading of "loop" to be either
an eyeknot or a bight (I can't even bring myself to say "the
rug is made of many bights..."!).

Although if you consult ABoK #32 & 40 you will find
good challenge to the above, and also the defined (in
the glossary) "turn" which denotes a full circle/360degrees.
.:. Knotting nomenclature is a challenge both in cleaning
up and in setting (a) straight (course) !!

Quote
When is a turn a turn and when is a loop a loop?

At some point, we have to stop and agree on terminology - and this is something I have pointed out several times over the past few years. It appears that elements within the IGKT still cannot agree on a standardized knotting terminology.
It's a tough task not even well started, IMO.  Although
we've pointed out some of the troubles, to a small (reading)
audience.  IMO, for specific technical discussions, it will
be necessary simply to try to avoid problematic terms
and to otherwise specifically define one's own terms, how
one is using/meaning terms.  (I don't hold hope that common
parlance will have the precision that possibly we might define
for technical talk.)

Quote
I would also comment that your 11th hour change of mind with the use of the term 'anti' is a bit late in the day. Why wait until now (at the very last minute) to waive the red flag?
I raised as described --recent turn (loopy?) of mind on
the consideration of hilarious bowline & ..., of *angle*
vs. *direction* --though there are fuzzy in-betweens
or rather neutral (perpendicular to axis of tension)
directions of the nipped parts.
And then a stepping back to ask of the point/purpose
of making some such distinction --gotta be a better
reason than merely "because we can" & "it makes
a divide (in quantity per division) for easier reference".
My initial thinking was the per-direction was a weak
guide to resisting the opening helix; now, I'm thinking
maybe it's *angle* rather than *which-side* as the
better indicator, though noting that compromises
and does-it-better/-worse can occur regardless
(along with the in-between, perpendicular angles
challenging the new classification).  --and esp. in the
knots that delay tucking through the nipping loop;
when the working end goes elsewhere and then...
is tucked through.
(Though having maybe 3, 4, or more classifications
might be a good thing : some will favor ignoring the
further-from-1010 cases as being "bowlines", but
they'll at least be attached at arm's length with
a known relation --whatever one calls them, then.)


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 03, 2016, 06:36:49 PM
Quote
Given my more recent thoughts/realizations about the lack of
a sure, practical-in-knot-behavior distinction based on the
tucking, it might all be "back to the drawing board".

This is worth some greater context, too :: the much-revised
paper IMO is straddling two noble aims, and I think compromises
its potential on one direction --of being a presentation of many
heretofore not well known *bowlines* that are worthy of
consideration/knowing;
and making some profound statement about *bowlines*,
of their essence, workings, and what-have-you.  It is this
latter venture that is problematic and rich with challenges
and points of view, and going much into such discussion
will likely be offputting to those who simply want some fresh
insight into possible useful knots; they might turn away.
(The audience for this latter venture is relatively small;
that for the former might be more agreeable to fee-based
access, provided they get a *clean(er)* here's-the-goods/knots
presentation!?
 ;)

And, wow, would I realllllly like to see ONLY the "right" view
of bowlines, and NOT the "conventional" one!!  The whole
point of advocating for this view was to redress confusions
attributed (conjecture, but ...) to the conventional view.
But for the most part, for an effective part, conventional view
rules the day --as though the new doc. is to be read adjacent
to some old one.   <grumble grumble>


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on April 04, 2016, 04:19:06 AM
Quote
that now I am favoring looking at
the nipped part's angle rather than direction through
the central nipping loop.  !?  --as a reasonable (?)
distinction (rather than merely possible one) for *bowlines*.

Yes indeed...this is something that Xarax hinted at several times to me over the course over many emails (over several months) - including emphasizing the direction each leg of the collar takes in relation to the nipping loop. Although I found it difficult to photograph and adequately describe the concept in words. The logical solution (for me) was to look at the direction from which the returning eye leg enters the nipping loop. Furthermore, when attempting to tie a Bowline by following the 'anti' direction - the returning eye leg can not collar the SPart - it doesn't work - you can only collar the ongoing eye leg (or alternatively create a Myrtle).

At some point though - a decision had to be taken - and the 'anti' concept had tipped the balance for me; despite having some reservations.

I personally want to see the matter settled once and for all...But, whatever decision is taken in the future - it MUST be capable of being consistently applied and also withstand peer review/scrutiny.

Quote
yes, by your
thinking the actual M. would then be "anti-M"

Indeed - I had to find a way to distinguish one type of Myrtle from the other.... and I was using the 'anti' term specifically in relation to Bowlines - and not trying to apply the concept to a broader set of knots. At the moment, the 'anti' direction seems to hold up - I haven't been able to detect any glaring flaws with the general concept of direction that the returning eye leg takes through the nipping loop.

It is not too late in the day to add another page showing the pitch angle / canter of the nipping loop relative to the returning eye leg as an alternative theory.

Quote
and making some profound statement about *bowlines*,
of their essence, workings, and what-have-you.  It is this
latter venture that is problematic and rich with challenges
and points of view, and going much into such discussion
will likely be offputting to those who simply want some fresh
insight into possible useful knots; they might turn away.

Well you know Dan - much of what I wrote down in the paper needed to be documented - if not by me - then someone else surely would have done it at some stage? Part of my driving motivation was to gather up all the current best thinking and document it. With people such as yourself, Xarax, knotsaver, SS369, Derek and a host of others - why not pick everyones brains and develop a comprehensive paper on the subject?

For me, the issue now is whether I have made the right decision to lock the paper down and attach a $ value to it. I have had little by way of reward for my efforts (probably more grief than happiness truth be told) - and it did require a significant and sustained effort on my behalf.

Quote
But for the most part, for an effective part, conventional view
rules the day --as though the new doc. is to be read adjacent
to some old one.   <grumble grumble>

I have come to believe that the 'conventional view' actually shows the collar and its 2 legs better than the detail view. I think both views/aspects of the Bowline structure have merit. It depends on what you want to show. If its the operation of the nipping loop - then the 'detail view' is best. However, if you want to emphasize the collar, the 'conventional view' works best (in my opinion). And this is not echoing anything from Xarax...he simply impressed upon me the important of the collar and its structure (ie its 2 legs) - and this made me realize that the 'bight' structure was really a composite of several individual elements. Once the idea of the 2 legs hit home...I just had to devise names that were reasonable for each leg. A few tries (and criticism from Xarax) eventually led me to speculate that 'entry' and 'exit' were reasonable terms.

Quote
Although if you consult ABoK #32 & 40 you will find
good challenge to the above, and also the defined (in
the glossary) "turn" which denotes a full circle/360degrees.
.:. Knotting nomenclature is a challenge both in cleaning
up and in setting (a) straight (course) !!

My view is that Ashley was not entirely clear on his distinctions between loops and turns. So I turned to Budworth to see if I could find something more concrete - and the solution appeared to be the 'Round turn and 2 half hitches'. On the fact of it, Budworth seemed to be favoring a definition where the rope encircled some object such as a post, a rail, etc.
This is one of the reasons why I favor a stricter definition of a nipping loop in that it must be loaded at both ends - as it creates more well defined parameters. Xarax favored using terms such as; 180 U turn, 360 degree turn, 540 degree round turn to achieve greater precision (which I tend to agree with). One can look to the CMC '540' rescue belay device as an example of mainstream use of the concept of 540 degrees round turn.

EDIT:
I am adding one extra page on the concept of TIB.
I think it was Xarax who posited that all Bowlines - with the tail exiting through the collar along a parallel pathway with the SPart - ought to be TIB. Is this general hypothesis correct? For example, I note that the standard #1010 Bowline is not TIB. And yet, I can untie the #1010 Bowline with Yosemite finish by way of reverse engineering it without access to either end.
I can find no way to reverse engineer the standard #1010 Bowline without access to either end.

...

I want to be done with the Bowlines paper... I need to move on to another worthy project. And this would be 'Rope Joining Knots for increasing the length of abseil ropes'.

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 05, 2016, 03:36:33 AM
Quote
I think it was Xarax who posited that all Bowlines - with the tail exiting through the collar along a parallel pathway with the SPart - ought to be TIB. Is this general hypothesis correct? For example, I note that the standard #1010 Bowline is not TIB. And yet, I can untie the #1010 Bowline with Yosemite finish by way of reverse engineering it without access to either end.
One doesn't posit morals!
It shouldn't be hard to disprove the X's "posited" wish
--just do some more fancy weaving with the tail before
making the prescribed final exit.  You could even tie a
knot in it --a nonTIB one!

Quote
I need to move on to another worthy project. And this would be 'Rope Joining Knots for increasing the length of abseil ropes'.
ARJs --abseil=ropes-joining knots,
end-2-end knots.

Along these lines, I've been playing with making the
initial turns or loops to go in opposite vs. side-by-side
directions, hoping to get the knot to entail each end
making a "loop" and not "arc" into the nub --which
would likely improve strength (which isn't part of the
main design goal, I know); but I've not been satisfied
with the results (they might look promising, but then
in different materials ... not so much).


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on April 06, 2016, 03:50:42 AM
Adding a new page to the Bowlines paper.

Topic is 'TIB' Bowlines.

Comments please...

Not sure who started the whole TIB investigation and then development???

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on April 06, 2016, 10:44:22 AM
Topic is 'TIB' Bowlines.
Comments please...

Mark,
Scott's simple lock Bowline isn't TIB, but the tail exits through the collar along a parallel pathway with the SPart (doesn't it?).
(A TIB variation of Scott's Bowline is at
http://igkt.net/sm/index.php?topic=4517.msg30269#msg30269)

I've found this topic about Xarax' position:
"Retuck the Tail end through the collar - you may end up with a TIB bowline."
http://igkt.net/sm/index.php?topic=4695.msg30329#msg30329

Ciao,
s.

Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on April 06, 2016, 02:42:09 PM
Thanks knotsaver.
I'm glad I was only asking the question about TIB and not making any absolute declarations of fact.
The issue for me now is what is the current best theory about what makes a particular Bowline TIB?

I suspect that in the case of Scott's locked Bowline - the S bend weave that the tail takes in order to exit via the collar is the cause of failing to be TIB.

How many other Bowlines with the tail exiting via the collar alongside the SPart are not TIB?

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: enhaut on April 06, 2016, 08:46:46 PM
Bravo, this page on TIB bowlines is important, you also provided an excellent tying method.
The yellow dot marking the collar to be is a nice touch,but imho you should add a red one in the frame number 3 in order to show the tip of the eye to be.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on April 07, 2016, 05:06:05 AM
Quote
imho you should add a red one in the frame number 3 in order to show the tip of the eye to be.

Thanks enhaut...implementing your suggestion now.

Also fixing a few grammar issues.

I am still trying to find a theorem for what makes a particular Bowline TIB.

In Scott's locked Bowline, the tail follows an S bend before exiting through the collar and parallel to the SPart. This results in the structure being non-TIB. But is Scott's Bowline the exception rather than the rule?
What was Xarax's theorem?

I'll have to email him...
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on April 07, 2016, 01:31:20 PM
Please try this:
tie a Standard Bowline (#1010) with a strangled double overhand knot (around the returning eye-leg, tail towards the tip of the eye (= around the ongoing eye-leg, tail towards the nub)) and then retuck the tail through the collar along the parallel pathway with the SPart...and try to "UnTIB" (untie without using the ends)
and as if by magic...
:)
(Edit: BTW the TIB method to tie the knot is simple...)
But, if we tie an overhand (single, double...) around the returning eye-leg, with the tail towards the nub we can't UnTIB! :(

Xarax, IIRC, posites and shows that if we simply (immediately) retuck the tail through the collar along a pathway with the SPart of a standard Bowline (#1010 and #1034.5) we obtain a TIB Bowline (they are 4).
(http://igkt.net/sm/index.php?topic=4695.msg30330#msg30330)
Now we can extend the result by adding overhand (single, double...) knots as we've seen above.
--
Mark,
you could mention the method (as in ABok #1080) to discover/invent TIB Bowline suggested by Dan_Lehman,
(see http://igkt.net/sm/index.php?topic=4695.msg30331#msg30331)

Another way to look at this discovery/invention by formation
is to suggest another method of formation : insert a bight
through the turNip (and some other bases) and then do
"the "back-flip" (my term) as is done for the bowline in
the bight
--which necessarily sweeps the tail back through
the just-formed collar.

--
ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on April 07, 2016, 06:50:00 PM
BTW the TIB method to tie the knot is simple...

Here it is: a class of locked TIB Bowline:
(it's a variation of Dan_Lehman's suggestion):

- Tie a noose
- with the (slipping) SPart tie an Half Hitch (the future nipping loop) around the  eye of the noose
- back-flip the eye of the noose
- form the eye of the Bowline (use the nipping loop to find the ongoing eye-leg)

you will find the structure (the nub) of the noose around the returning eye-leg (or, reversed, around the ongoing eye-leg) of the new locked TIB Bowline.
--
ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on April 08, 2016, 01:37:05 AM
I'm not sure if I like you anymore knotsaver... :)

You are causing me to further extend the length of my Bowlines paper - and hence, further push back the completion date.  :o

...

But, thank you very much for your input!

I always felt my paper needed to elaborate on TIB Bowlines and the whole concept of TIB in general.

My initial thoughts focused on just a one page summary...but, I see now that this is not possible.

I have to admit that I didn't know about the TIB capable Bowline with strangled double overhand lock on returning eye leg. And your interesting TIB tying solution.

This is all extremely important in my view and I thank you.

I should also point out that it is really easy to 'reverse engineer' knotsaver's above-mentioned locked Bowline - I am sticking with this term. I have personally found 'reverse engineering' a knot a useful tool to determine if the structure is TIB.

By the way, I have received an email reply from Xarax about his theorum on TIB Bowlines. Its all Greek to me...but, I am working through it all now...

EDIT: I wonder if I am 'allowed' to post Xarax's comments re TIB Bowlines on this forum? I am unclear what the IGKT moderators rules are for me acting as a 'proxy' for Xarax?

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 08, 2016, 05:42:23 AM
Adding a new page to the Bowlines paper.

Topic is 'TIB' Bowlines.

Comments please...

Not sure who started the whole TIB investigation and then development???

Mark G
It wasn't here, and it wasn't via the Net, either :
connections were knotted together the ol'-fashioned
way, by snailmail and Knotting Matters (newsletter,
mailings of physical paper & ink), circa 1987.

Two of knotting's keener innovators, viz. John Smith (UK)
and Pieter van de Griend (Nederland) brought out the
fact that a knot that the former had presented in KM#018
(Spring 1987) was in fact TIB --noted by his comment
(as sparked by private correspondence from PvdG) published
in the next issue (Summer 1987).  That's nigh 3 decades ago.
(And although I came around to the same discovery, on my
own, IIRC --even if this speaks poorly of my reading/research
skills (or sometimes even of my memory : *inventing* a knot
more than once!), I'm pretty sure that it was well later.)

The knot that was presented is the one I've been advocating
for to replace in prominence/usage the Yosemite bowline
--you have it now in the document, but still not with suitable
emphasis.
.:.  It should be HERE, vice what your have as the 2nd, AND
as what gets the step-wise tying imagery.  The idea is to promote
a better knot than the commonly promulgated YoBowl!

Re(-re)ading the old articles, I'm reminded of another point:
the **nub** matches that of angler's/perfection loop (#1017)
but one's ends are the other's eye legs (!).  (And I've not been
clever enough to figure out if one is TIB must the other be?!)

Quote
I've found this topic about Xarax' position:
"Retuck the Tail end through the collar - you may end up with a TIB bowline."
Yes, that is a good point --the tuck amounts to a sort
of *retreat* which might beget TIB status.  BUT it
does not ensure it, and the document should not imply
that it is an open question, when it is easily proved false!


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on April 08, 2016, 07:00:40 AM
Quote
the tuck amounts to a sort
of *retreat* which might beget TIB status.  BUT it
does not ensure it, and the document should not imply
that it is an open question, when it is easily proved false!

Actually, my question was:

For those Bowlines which are proven to be TIB - do they all have the tail exiting through the collar and then along a parallel pathway with the Spart?
In other words, is it possible for a Bowline to be TIB - with the tail not exiting via the collar?

This is what I am trying to confirm or disprove!

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on April 08, 2016, 08:08:18 AM
I'm not sure if I like you anymore knotsaver... :)

You are causing me to further extend the length of my Bowlines paper - and hence, further push back the completion date.  :o

I'm sorry Mark ;), but you asked for comments :) ... I think it's because of the time zone :)
(you are welcome).

I have to admit that I didn't know about the TIB capable Bowline with strangled double overhand lock on returning eye leg. And your interesting TIB tying solution.

Neither did I!
Please try tying the double overhand lock on the ongoing eye-leg, I will post some pictures as soon as I can.
I've tied a TIB Bowline with a girt hitch collar (a 'complex' collar, is it a Bowline?) and with the tail exiting through the collar, is it a known knot? I think it's interesting... I will post a picture.

EDIT: I wonder if I am 'allowed' to post Xarax's comments re TIB Bowlines on this forum? I am unclear what the IGKT moderators rules are for me acting as a 'proxy' for Xarax?

I miss Xarax ('s comments) on this forum! :(
--

ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on April 08, 2016, 08:41:11 AM

For those Bowlines which are proven to be TIB - do they all have the tail exiting through the collar and then along a parallel pathway with the Spart?
In other words, is it possible for a Bowline to be TIB - with the tail not exiting via the collar?

What about ABoK #1074?
How do we consider it? (Ashley named it Bowline with a bight).
(BTW, the eye of the Bowline could enter the bight and we could tighten the bight)
ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 08, 2016, 05:23:04 PM
For those Bowlines [that] are proven to be TIB ,
 do they all have the tail exiting through the collar ...

This is what I am trying to confirm or disprove!

Mark G
This is simply shown to be false.  Browse ABoK and you'll
see some, if not making your own, per recipe of the question.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on April 09, 2016, 03:10:22 PM
Please try tying the double overhand lock on the ongoing eye-leg, I will post some pictures as soon as I can.

attached pictures:
TIB Bowline with strangled double overhand lock on the returning and on the ongoing eyeleg.
The knots are not so nice, they are a little bit bulky...but they are TIB! :)
--

BTW the TIB method to tie the knot is simple..

We can "improve"  (?!) the method using a generic TIB Hitch (for the nipping loop [and for the collar])

- Tie a (an obviously TIB) noose
- with the (slipping) SPart tie a TIB Hitch (the future nipping loop) around the  eye of the noose
[<optional> - with the eye of the noose tie a TIB Hitch (this will be the complex collar)]
- back-flip the [TIB Hitch formed with the] eye of the noose
- form the eye of the Bowline (use the nipping loop to find the ongoing eye-leg)

you will find the structure (the nub) of the noose around the returning eye-leg (or, reversed, around the ongoing eye-leg) of the new locked TIB Bowline.
--

I've tied a TIB Bowline with a girt hitch collar (a 'complex' collar, is it a Bowline?) and with the tail exiting through the collar, is it a known knot? I think it's interesting... I will post a picture.

the knot I've tied is a single eye version of a knot suggested by Tex at
http://igkt.net/sm/index.php?topic=5385.msg36531#msg36531

At
http://igkt.net/sm/index.php?topic=4343.msg29871#msg29871
there is a Bowline with a Clove Hitch collar (posted by SS369)
but without retucking the tail trhough the Clove Hitch.
--

About the TIB Bowline with the tail exiting/not exiting via the collar, I think the simplest (and maybe the best) are those with the tail exiting via the collar, to obtain the others (with tail not exiting via the collar) we have to use a slipped loop/bight with the tail somewhere.

--
A question: (about the Bowlines) is it important the concept of midline TIBness (I can use both ends) and end of line (end of a rope) TIBness?
--

ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 10, 2016, 05:47:18 AM
--
A question: (about the Bowlines) is it important the concept of midline TIBness (I can use both ends) and end of line (end of a rope) TIBness?
--
A good point, and there are four cases:
1) TIB (for use with just one end qua SPart)
2)    "   with either end usable qua SPart ("EEL", was it?))
3)    "  as in #1 but also allowing "through (end-2-end)" loading
          (making what is called a "directional eye knot")
4)   "   as in #2 with #3's addition.

The butterfly knot is generally regarded to meet #4's demands,
and the directional fig.8 #3's,
with the bowline on a bight #2's
and my "hilarious bowline" just #1's.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on April 18, 2016, 10:00:25 AM
Thank you, Dan_Lehman!
I'm sorry but I've not found the hilarious bowline...
Could you show it, please?
thanks.
Ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 21, 2016, 04:48:03 AM
Thank you, Dan_Lehman!
I'm sorry but I've not found the hilarious bowline...
Could you show it, please?
thanks.
Ciao,
s.
I will *tell it* (again), for now.

rope runs from right-to-left (SPart right, to-become-eye left),
making the nipping loop with a clockwise turn,
crossing point at bottom (6:00),
on-going eye leg crossing OVER SPart;

at suitable length for eye, make the U-turn ANTI-clockwise
so to bring returning eye-leg back below & beside on-going
one, and crossing back over SPart;

at which point, turn this working end clockwise down
under the SPart (and now, roughly, pointing down from 6:00).

HERE, there is a choice :: to make hilarious bowline
or a similar one (described after...).

FOR H.B., take the working end around (continue
clockwise) OVER the adjacent eye legs;

and now, form a bight and tuck this in through the nipping
loop, from back to front (i.e., towards view) --so, crossing
9:00-ish side of loop UNDER and bring bight out from that.
The substance of the bight --the material bulk and resistance
to being bent/folded-- is what is hoped to keep the nipping
loop *loopish* and not opening (too much) into a helix.
So, dress & set the knot accordingly, working to minimze
the collaring of the eye legs, hauling on the bight end to
get this snugged, which will tend to rotate the nipping loop
opposite the direction it will want to move when loaded,
which is towards opening into a helix --a little of which might
be fine for the situation (YMMV).
.:.  This is a knot that looks fine for putting in an eye w/o ends,
and maybe *instructive* about knot strength in having the
SPart in a curvature of diminishing radius (something that might
obtain more in some materials than others).


That other-like-knot choice would have one form a bight
at the decision point (working end at the 6:00 area after
turning around the SPart), and tucking out through the
loop immediately, front to back (away from view).
AND THEN, though, one must draw the eye through the
tucked bight and snug the latter around it, which will give
more sure resistance of the SPart opening into a helix,
though it can do so, depending on materials and so on.

In the H.B., one might be able to untie it by simply pulling
on the tail and spilling the tucked bight --though it wasn't
the point of the tucking, which was need (TIB) and bulk.

Generalizing the tying *aspects*/techniques/... presented
above can lead to many more such eye knots, and some
look great (there might be elements of immodesty showing ...).  ;)


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on April 21, 2016, 11:01:26 AM
I will *tell it* (again), for now.

Thanks (again) Dan!
If I'm right this should be the Hilarious Bowline (look at the pictures)
If the eye enters the bight and then we back-flip the bight, the obtained Bowline should meet #4's demands (as the butterfly), am I right?

Ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 21, 2016, 08:33:01 PM
Yes, nearly :: in the original --which might have no
claim to preference; just noting the fact--, the tucked
bight didn't have crossed legs, so the curving SPart
reached farthest and *bit* into the tail-leg of this bight.

NB: in the version as you set it, the SPart's loop is well
oriented against being a helix --it has some movement
to give, and still be *loop* (so, you show the desired
setting).  Loading surely will turn you loop more into
the plane with axis of tension, and then maybe beyond
that, towards the helix'd state.

As for your backflipped variation, I'm not following this
to get similar look :: yours shows still a collar around
the eye legs, but that is what was to be backflipped?!
(or I need to scrutinize the images better!)


Thanks, (for evidence that words CAN work!)
--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on April 22, 2016, 11:38:14 AM
Just advising that I have uploaded VER 2.6 of the Bowlines paper.

All password restrictions have been removed.

Hopefully the 2 new pages on TIB are acceptable content?
I have only provided an overview of TIB - it is not intended to be exhaustive...

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on April 22, 2016, 03:42:31 PM
:: to make hilarious bowline

Dan,
the Hilarious Bowline is substantially a reversed slipped Tugboat A!
[Edit] or, better, a slipped Harness Loop (Artilleryman's Knot, ABoK #1050) (the reversed Tugboat A and the Harness Loop have the same structure). [/Edit]
--

As for your backflipped variation, yours shows still a collar around the eye legs, but that is what was to be backflipped?!

Thanks, (for evidence that words CAN work!)


The back-flipped collar is on the right in the picture (remember in my version the legs of the bight were crossed)... I should attach a better picture...
The instructions were clear!  ;)

Just advising that I have uploaded VER 2.6 of the Bowlines paper.
Hopefully the 2 new pages on TIB are acceptable content?

Thank you Mark!
please, notice that you repeat the same phrases at p. 12 and p. 13.
--
Ciao,
s.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on April 23, 2016, 12:59:08 AM
VER 2.6a (23 April 2016) is uploaded.

Thanks knotsaver - you have a good eye for typos / errors.

Hopefully this is good to go now?

I want to be done/finished with this project...!

Mark
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 24, 2016, 07:33:57 PM
The back-flipped collar is on the right in the picture (remember in my version the legs of the bight were crossed)... I should attach a better picture...
The instructions were clear!  ;)
Are you starting with H.B. then?
--and not the "immediately tucked" bight of the
variation as I presented (where the tucking goes
in the opposite direction, and the eye-tucking thus
is necessary for integrity)?!


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knotsaver on April 25, 2016, 04:54:23 PM
Are you starting with H.B. then?

Yes, it was referring to the H.B.

VER 2.6a (23 April 2016) is uploaded.
Thanks knotsaver - you have a good eye for typos / errors.
Hopefully this is good to go now?
I want to be done/finished with this project...!

Mark, two typos:
p.13 ln.1 "..TIB be tucking.." is "TIB by tucking" (isn't it?)
p.16 the 'Anti Bowline? (refer to page 38)
--
about the TIB Bwl with strangled double overhand, is the external curve made by the tail irksome/insecure? have you considered the double overhand tied around the ongoing eye leg (with the tail towards the nub)? as I showed at reply #453
http://igkt.net/sm/index.php?topic=4480.msg38584#msg38584
--
About the Myrtle... no, no... I'm joking! :D

Ciao,
s.



Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 27, 2016, 11:36:58 PM
 
Quote
Dan Lehman reported that the TIB concept most likely began circa 1987 through the work of two innovators ? John Smith
and Pieter van de Griend ? and was reported in ?Knotting Matters? issue #19.
Rather than the "TIB concept" being cited, it was the
particular bowline shown in the document newly crediting
me with "Lehman's lock" --'twasn't mine (first).
(If anything, I've beat Alan to one of his locks, and
stand unique in the EBDB loop-locking --but I seek
no recognition for either (and am pretty sure that
where I got the Lee-like overhand finishing lock
it was in slightly different bowlines (i.p., in a later
case, a double-eye variation, which is also TIB).)

There is one new and should-be-excised "larks foot"
vice "larkshead" --let's NOT echo the Brit's mistake!
(p.24).

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 27, 2016, 11:58:49 PM
About the Myrtle... no, no... I'm joking! :D
Well, I remain dismayed by the "anti-bowline" bit,
and the myriad myrtles muddle isn't helping my
disposition.

Yesterday (2016-04-26), I came up with this conjecture:
if one makes two locking loops with the tail
(aka "returning eye leg", "working end") through the
central nipping loop,
then ALL resulting knots --entering from either side
and turning-tucking away or towards eye,
will be okay !
--sort of a safety measure,
along the lines of tying a "back-up" offset water knot
to an initial one : that guards against all (mis)orientations
of thick-thin ropes & dressings.  (Or so I'll believe fairly
strongly until Mobius puts it to test w/his EDK-defeating
cord and proves otherwise!)
These knots will likely take a little care to set tight,
holding one looping reasonably tight while then
making the nipped & counter-nipping-in-return
looping tight within/around it,

In specificity, though, I like the anti-bowline orientation
(non-Myrtle thus) with the wrapping going towards
(note that the Myrtle wraps away from) the eye.
And position the tail's tuck so that it sits sort of atop
the two parts bearing at the nipping loop's crossing
point --make a sort of triangular bunch of nipped parts.

This "doubled" wrapping of the tail will give adequate
"slack security" in many materials --YMMV.  (Just as I
found in one that the EBDB's wrap simply gave out
with a little time, no matter my tight setting.)


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on April 28, 2016, 12:25:05 AM
Quote
Constant Xarax has posited that Bowlines with a Jones polynomial of 1 are TIB. In other
words, they are equivalent to the ?unknot?. But, this statement is only true for rather simple
structures, which have a crossing number smaller than 18.
THIS says exactly what?! of any significance?

Let's start with "Bowlines with a ..." :: please show me
some --with ANY value (1 or 2 or ...).  Mathematical
knots are that; bowlines are practical knots not closed
circles (and NB closing #1010 requires making a choice
of directions and resulting math. knots!).

And were it true --well, by definition the UnKnot is
TIB and is what the JP of "1" means--,
how can that be constrained by number of crossings?
--if one can get it (the "1") from however-many-crossed
a knot you have, then ... BINGO!
???

This smells like a bad product promotion in a movie;
it ads nothing but puzzlement to the document.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on May 01, 2016, 11:01:32 AM
Bowlines analysis VER 2.6b (01 May 2016) has been uploaded.

All password restrictions have been removed.

knotsaver, I have corrected the typos...

Dan, I have removed the reference to 18 or less knot crossings.

I have also done some more work to fix and improve the section of TIB Bowlines. Also changed the wording on the origins of TIB...

Some changes to the intro pages have been made.
Lehman lock Bowline has new wording added.

Dan, the concept of Anti Myrtles will remain as is for now. It fits with the overall theory - so changing 'anti-Myrtle' would have an impact on the overall concept of 'Anti'. If you really have major concerns with the whole concept of 'Anti' - I would would need to see a full draft wording from you outlining your latest theories...

Other than that, hopefully the paper is of acceptable quality now?

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on July 15, 2016, 04:17:17 PM
Finally added a conclusion.
Took me a while...

VER 2.7a is now ready for download from the PACI website.

Also added Xarax's Ampersand Bowline.

Comments are still welcome...

Mark G

EDIT NOTE: Now VER 2.7a ... expanded some final thoughts about Scott's locked Bowline. Having giving the matter some considerable thought, I feel this structure is a strong contender for the overall prize of simplicity and effectiveness. Also added further info about historical use of Bowlines in early mountaineering (in particular Portuguese Bowline #1072) - because it had the advantage of being able to wrap a few extra turns around the body to pad it out - before safety harnesses were introduced).

I think this is the last modification to the paper for a while. I feel it is complete and worthy of presentation to the IGKT!
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: knot rigger on July 15, 2016, 04:57:17 PM
Mark

Nice work.  Your paper is impressive and you with each revision you continue to improve upon it. 

thank you
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: SS369 on July 15, 2016, 09:48:59 PM
I like your work Mark.
Thank you for your ongoing commitment to this project!

SS
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alanleeknots on December 21, 2016, 08:23:28 PM
Quote
Dan Lehman reported that the TIB concept most likely began circa 1987 through the work of two innovators ? John Smith
and Pieter van de Griend ? and was reported in ?Knotting Matters? issue #19.
Rather than the "TIB concept" being cited, it was the
particular bowline shown in the document newly crediting
me with "Lehman's lock" --'twasn't mine (first).
(If anything, I've beat Alan to one of his locks, and
stand unique in the EBDB loop-locking --but I seek
no recognition for either (and am pretty sure that
where I got the Lee-like overhand finishing lock
it was in slightly different bowlines (i.p., in a later
case, a double-eye variation, which is also TIB).)

There is one new and should-be-excised "larks foot"
vice "larkshead" --let's NOT echo the Brit's mistake!
(p.24).

--dl*
====

Hi All,
        I know "Lehman's lock"  EBDB loop-locking.
        Can anyone please tell me what is the knot here- "(and am pretty sure that where I got the Lee-like overhand finishing lock
        it was in slightly different bowlines (i.p., in a later case, a double-eye variation, which is also TIB).)"
        谢谢 alanlee.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on December 21, 2016, 09:59:17 PM
        Can anyone please tell me what is the knot here-
 "(and am pretty sure that where I got the Lee-like overhand finishing lock
        it was in slightly different bowlines
 (i.p., in a later case, a double-eye variation, which is also TIB).)"
        谢谢 alanlee.

One can see an invitation to such a finish in the venerable
bowline on a bight :: take the unloaded tail and tuck
it back out through the central nipping loop, which thus
makes an overhand knot structure.  (It might be better
done in this case with the strand of the twin parts that will
be pressed into by its loaded twin!?  Of Mark's paper's image
on p.41, one would reverse his tail/SPart relation, thus.)

You show the structure on Mark's p.46.

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alanleeknots on December 22, 2016, 04:00:50 AM
        Can anyone please tell me what is the knot here-
 "(and am pretty sure that where I got the Lee-like overhand finishing lock
        it was in slightly different bowlines
 (i.p., in a later case, a double-eye variation, which is also TIB).)"
        谢谢 alanlee.

One can see an invitation to such a finish in the venerable
bowline on a bight :: take the unloaded tail and tuck
it back out through the central nipping loop, which thus
makes an overhand knot structure.  (It might be better
done in this case with the strand of the twin parts that will
be pressed into by its loaded twin!?  Of Mark's paper's image
on p.41, one would reverse his tail/SPart relation, thus.)

You show the structure on Mark's p.46.

--dl*
====

Hi All,
        I have a few pictures here, just to make it easy for our reader.
       
        First picture, hopefully I read it right, Bowline on the bight is safe enough for what it suppose to do.
        As Dan suggest, I don't think is worth it, by adding more tuck, you are creating more work and also the
        unnecessary part , just over kill it  and you don't gain much.

        Second and third pictures is "Lee's locked Yosemite Bowline" on (Mark's paper's image on p.46)
         谢谢 alanlee.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on December 30, 2016, 09:00:55 PM
First picture, hopefully I read it right,
Bowline on the bight is safe enough for what it suppose to do.
 As Dan suggest, I don't think is worth it, by adding more tuck,
you are creating more work and also the
 unnecessary part , just over kill it  and you don't gain much.

Firstly, you OVERead it right --you go too far by bringing
the yellow tail fully around those parts and back out through
the collar.  Rather, I would (1) use the white side/position,
and (2) just do the tuck at issue VICE going out of the collar.
And this does give one the gain of having this locking structure
to tighten, which otherwise the knot does NOT have (maybe
if you "SS369" it and haul the collar(s) down tight upon
the SParts, and tighten all 'round; but this will not be done!   ;)  )

But, even what you show will give such tightened security-when-slack,
unlike the original. (It gives an "end-bound" tightening.)

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on October 31, 2017, 06:00:58 AM
VER 2.8 (31 OCT 2017) is now uploaded.

Direct link to page: http://www.paci.com.au/knots.php

Changelog:
[ ] updated page 1
[ ] main image on page 7 has been changed - and i think improved (took me a while but hopefully its better than before)...see image below for concept.
[ ] page 8 now amplifies that most images are loosely tied with deliberate short tails
[ ] swapped position of Bowline on-the-bight
[ ] conclusion has been re-written...Alan Lee's 'link' Bowline now featured
[ ] no change to section on anti-Bowlines / and 'Myrtles'...unless Dan Lehman is prepared to send me copy of his analysis - and if so, I could insert it into the paper :)


...

Comments welcome

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on October 31, 2017, 09:43:55 PM
VER 2.8 (31 OCT 2017) is now uploaded.

Direct link to page: http://www.paci.com.au/knots.php

Changelog:
[ ] page 8 now amplifies that most images are loosely tied with deliberate short tails
I disagree with the "loosely tied" : SOME of the knots are so,
but many are pretty well tied.  .:. I'd soften this assertion,
as one doesn't want to imply that folks should SS369 their
knots --i.e., haul hard on the tail and crunch a sharp bend
into the SPart.

Well, yes :: look at your nice presentation  (p.30) of the
common knot under various loadings --presumably you
begin as shown and don't count that at too loose.  Well,
most of what is in the paper is of that sort of setting,
right?!  (Firm cordage often begets some looseness.)

Quote
Comments welcome
Dang sad to see after X's & my strong urging
that so many --most-- of the knots are shown
from the WRONG side, which the paper does
admit hides important info.  Now, for some of
them --i.p., my mirrored bwl-- that might
be a good thing, with a sufficient "preponderance
of evidence" showing things write (the m.b.
benefits in showing that back'n'forth tucking of
its tail.

"Lark's foot" is a British misnomer, which the late
knot researcher Bob Thrun attributed (as likely)
to a book by Bill March (he did a few).  "Lark's
HEAD" is prior and otherwise substantiated,
i.p. by noting the French term.

Whoa, calling p.23's huge-collared knot "stable"
is beyond the pale off base --that thing can collapse,
YMMV on cordage (lesser looseness has seen capsizing).
I have noted some yachting knots quite loose like this,
but it's hardly the thing to assert is in any reasonable
way assuredly so.  (Granted, this too is my opinion
of the sheepshank, which has some kind of history
of usage apparently devoid bad results; but don't expect
me to depend upon it (though I have in fact tried out my
fears in shortening rope working my stressing pulley,
and so far am okay).

Re p.38 knots,
PUT A 2ND LOOP-TUCK OF TAIL IN BOTH,
and they both become stable (and with an
extra dia. of rope in the nipping zone).

--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on October 31, 2017, 09:45:35 PM
nb : YoBwl is also TIB.
 :)
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on November 02, 2017, 06:13:33 AM
VER 2.8a (02 NOV 2017) is now uploaded.

Direct link to page: http://www.paci.com.au/knots.php

Changelog:
[ ] fixed a few minor grammer / typo errors throughout the paper
[ ] amended page 8 per Dan Lehmans assertions about the number of 'loosely' tied knots
[ ] improved Janus Bowline images on page 53

Per Dan Lehmans comment re depicting the 'detail view' versus 'conventional view'...
Quote
Dang sad to see after X's & my strong urging
that so many --most-- of the knots are shown
from the WRONG side, which the paper does
admit hides important info.

I am of the view that this paper does spend enough time emphasizing the detail view - not sure how much farther one can go in the paper...? Is is not good enough in your view? Specifically which pages do you believe need to be amended (and which photos)?

Dan Lehman comment about TIB yosemite Bowline...
Quote
nb : YoBwl is also TIB.

Not sure about this point...The #1010 derived Yosemite Bowline was already shown as being TIB.

Dan Lehman remark about page 23...
Quote
Whoa, calling p.23's huge-collared knot "stable"
is beyond the pale off base --that thing can collapse,
YMMV on cordage

No comprendy...what image is being declared 'stable' on page 23? Which version of the Bowlines paper are you reviewing?
Am confused...


Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on November 02, 2017, 10:04:35 PM
Per Dan Lehmans comment re depicting the 'detail view' versus 'conventional view'...
Quote
Dang sad to see after X's & my strong urging
that so many --most-- of the knots are shown
from the WRONG side, which the paper does
admit hides important info.

I am of the view that this paper does spend enough time emphasizing the detail view - not sure how much farther one can go in the paper...? Is is not good enough in your view? Specifically which pages do you believe need to be amended (and which photos)?
Well, the initial and some following pp have stoopid
view, not the Right One!  --along w/many others.
At one point, I thought that most images were Right'd
& not Stoopid'd.  <sigh>

Quote
Dan Lehman comment about TIB yosemite Bowline...
Quote
nb : YoBwl is also TIB.

Not sure about this point...The #1010 derived Yosemite Bowline was already shown as being TIB.
Okay, good --sorry I just quick-read and missed ... .
I suspect that most climbers don't know this.
(though it might not do much for them if they did)

Quote
Dan Lehman remark about page 23...
Quote
Whoa, calling p.23's huge-collared knot "stable"
is beyond the pale off base --that thing can collapse,
YMMV on cordage

No comprendy...what image is being declared 'stable' on page 23?
Which version of the Bowlines paper are you reviewing?
Am confused...
The center image with BIG collar has this box'd comment:
"The nipping loop remains stable because the collar
 is prevented from folding down."

Well, not so surely in many circumstances, though
well enuff for some show'n'tell maybe,  But it gives
the wrong impression, IMO.

 - - - - - -

Now, for some dates of interest, maybe.
Lee's Link Bwl is my #20020301f10:22,
and #2---b22 = similar with returning eye leg's
loop opp.-handed.  (AND both w/o the final
Yosemite tuck through the collar.)

(Oddly, my EBDB appears on a page of bwls.
dated 200204... but w/o date-stamping of its
own, and hardly a murmur of appreciation!?
--a note page of origin elsewhere might show
more.  (I don't have an easily searchable batch
of illustrations!)
)

And the Lehman8 --a decent tie-in for those
wanting Fig.8 body w/bowlinesque easier untying
is date-stamped/ID'd #1991-05-19 approximately.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: alanleeknots on November 06, 2017, 09:52:51 AM
Quote
Now, for some dates of interest, maybe.
Lee's Link Bwl is my #20020301f10:22,
and #2---b22 = similar with returning eye leg's
loop opp.-handed.  (AND both w/o the final
Yosemite tuck through the collar.)

Dan, Please bring in your knot, Xarax and I will not take away anything that not belong to us.
        謝謝 alan lee.
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on November 07, 2017, 02:59:07 AM
It's worth noting that the Lee's Link can be seen
as a Myrtle with a collar (vs. "wrap") extension
--something that occurred to me for the anti-bowline
variation.

(-;
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: agent_smith on November 18, 2017, 08:28:41 AM
VER 2.8b (18 NOV 2017) is now uploaded.

Direct link to page: http://www.paci.com.au/knots.php

Changelog:
[ ] page 14: amended accompanying text for 'EEL' image of #1034 1/2 Bowline
[ ] page 26: amended text for accompanying image of enlarged collar (per Dan Lehman feedback)
[ ] page 48: amended content of the historical background of Lee's link Bowline (hopefully Xarax will approve this time?)
[ ] page 61-64: Major rewrite of content in conclusion pages

...

This is likely the last update for this year (2017) and maybe most of next year...unless something important or significant occurs!

Mark G
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: siriuso on January 22, 2018, 08:20:55 AM
Hi Mark,
I have a few suggestions below.
1) In page 17, the lower 2 pictures at the left should also be marked as Eskimo Bowline (tail inside ring).
2) You use the 2 bowlines at the right (page 17) as an example on pages 32 and 39, but not include the Eskimo Bowline. For detail and clarity to the readers, I would like you to add a page regarding the 'RING LOADING' on Eskimo Bowline (Anti Bowline) after page 32. And a page too, regarding 'Applying the theory...(Anti Bowline)' on Eskimo Bowline after page 39.

yChan
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Dan_Lehman on January 23, 2018, 12:21:30 AM
... on Eskimo Bowline (Anti Bowline) after page 32.
Please note that Agent_Smith has taken and abused
Dan_Lehman's moniker "anti-bowline", which was in
the latter's use a general term to denote ALL of those
*bowlines* --here, the most general sense of this much
overloaded name-- in which the returning eye leg goes
through the central nipping loop in the opposite direction
to that for the (specific sense) bowline (#1010)
--of which the Eskimo bwl is but one example.
This btw is what the flow chart of pg. 19 shows (i.e.,
the general sense of "a-b").
Conceivably, this moniker will be better put aside for
something lacking the *hostile* sense of "anti-"!  For
now, it was just a "clockwise/anti-clockwise"-like term
of distinction, for handy reference.

IMO, "Eskimo bowline" (a) doesn't/shouldn't give offence,
and (b) doesn't itself apply to only one orientation of the
tail (inside/outside).

 - - - - - - - - - - - - -

Note that p.7's red-highlighted "region of highest strain"
is NOT that; rather, the high pressure comes --as images
later in this document show-- where the SPart turns hard
around the returning eye leg, the tail having been easily
drawn up, around, out of the heavy line of fire.  NOW,
one CAN dress the bowline such as to anticipate this draw
of the tail by setting the tail well back behind --in reference
to this particular image's orientation-- the returning eye
leg, so that the SPart's draw of it will only upon much
load bring it to where traditional images show the tail
beginning!!  This more fully gives two diameters
of bending; the rather unloaded tail material will more
readily compress per SPart pressure than does the
50%-loaded returning eye leg, and that I think will
benefit the SPart.  YMMV per material ... .  (no test
data to analyze re this and other aspects)

 - - - - - - - - - - - - - - - - - -

In the presentation of the Myrtle etc. there is much
good knotting lost (not presented) for want of simply one
2nd turn of the tail in ANY of the orientations --i.e., this
simple turn remedies the asserted flaws.  And if the author
does no more than merely "posit" superiority/inferiority of
two knots rather than offering a basis for this ranking,
the reader is cheated of anything to go on.
Beyond positing, thus, I'll note that a 2nd turn as urged
above will give a 3-dia. turn to the SPart and surer
gripping/security to the knot.  (One could even make
this additional diameter come via a collar/bight added
vice the 2nd turn --oh, the possibilities, varieties!    ;D


Further, note that were that heavily loaded BWII bowline
shown from the other face, or side, the viewer might see
that the "crossing point" no longer, or barely, had any
contact of SPart w/its following --that the circular nature
was pulling towards more helical shape, towards capsizing.
--which would change the structure from a bowline
into a pile-hitch noose!  And all in ONE knot (token)!
--not mere theory, but something seen in actual heavy
mooring lines.


--dl*
====
Title: Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
Post by: Harold Kahl on January 23, 2018, 05:47:44 AM