Author Topic: How to improve the security of the bowline. Two simple instructions.  (Read 12237 times)

alpineer

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #15 on: April 11, 2015, 07:33:24 PM »
  (But we can be certain that he can fill
many lines with keystrokes about "understanding" and blah!)
 

 alpineer likes this
 

 
 

Mobius

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #16 on: April 13, 2015, 12:30:54 PM »
Another point : what do you want as a "mid-line" eye knot?
--just something that is TIB ?!
--or something that can take all possible loadings
(i.p., loading through (end-2-end), and loading the eye
vs. either end?

I have hopes of finding a knot that is TIB and can be loaded end-2-end (e2e) or eye to either end (i2e). I have a bowline that I have been playing with in several different formats that I think is new. It is PET, TIB, easy to tie TIB (3 main easy steps that do not involve nefarious twists), fairly easy to tie as an end loop (7 pretty easy steps (harnessed on a cliff with finger gloves on perhaps), vs 4 similar steps for a R-hand bowline as a comparison) and is potentially secure under e2e, or i2e loads. The twin collar structure looks easy to untie as well, even after heavy loading. Also, the curves entering into/within the nub all look 'gentle' to me. So theoretically, it might be a good bowline.

I am quite keen to do my own trials on it first before releasing it here for critique (ridicule perhaps  :P ). My trials might only go as far as seeing if the knot collapses under strain (something a lot more than me just tugging on the knot furiously with all my might ;) ) and if it is easy to untie after load. If the knot looks promising to me I'll share it with the forum.

Quote
"Testing" by usage is the ultimate test, however
Well, it is something also to be not dismissed; but one can question
the thoroughness, even so --might some odd danger exist in what
seems an insignificant variation (such as just discussed re bowlines)?!
So, a methodical laying out of possibilities and then some intelligent
testing of them remains part of "ultimate", IMO.  --just building a
good checklist of considerations to note being considered and how
(since exhaustive testing is often difficult, one might "consider"
the condition in light of usage, things known otherwise, all the
while noting that it was not specifically tested).  E.g., consider
a mid-line eye knot being tested : this has been done, I think,
in two ways --through loading (sometimes; so the knot is loaded
qua end-2-end joint), and eve-vs-ONEnd (and in a separate test
specimen, new and *clean*/untainted) !!  Now, in actual-practical
usage, there might be loading that comes one way AND THEN
the other : will first loading reshape the knot such that the 2nd
loading ... at least gets a well different result (weaker, say, or
more disruptive of knot structure) than pure, clinical, testing
had indicated?  (You can see how test cases multiply so much,
even w/o the desired repetition!)

--dl*
====

I see your point. There are knots used 'successfully' everyday, that are potentially unsafe when they encounter the untoward (uncommon) circumstances that cause them to fail (perhaps at the cost of a life). Clinical testing seems to be a rarity in the knotting world, and I say that hoping not take anything away from those who have taken the time and effort to do some fine trials/comparisons.

Cheers,

mobius

[edit: fixed some typo's and sloppy writing]
« Last Edit: April 13, 2015, 01:52:36 PM by mobius »

agent_smith

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #17 on: April 13, 2015, 12:57:44 PM »
Quote
And Mark I think got that news re vulnerability from me, who recalls
reading some hearsay/rumor that some injured-in-fall rockclimber
was attempted to be airlifted out via an attachment to his still
tied tie-in eyeknot, clipping into the eye and ring-loading it,
and ... that turned out tragically.

If I can see further its because I have stood upon the shoulders of giants.  Hmmm, which famous man said that?

Ring loading is a known vulnerability of #1010 (right hand bowline).

Many vertical rescue technicians use and rely on a bowline as the principle interface knot connecting stretcher (ie litter) to haul ropes.   #1034 1/2  (left hand Bowline) is resistant to ring loading vulnerability.

Bowlines are also commonly used in rock climbing and mountaineering applications. Indeed, old photos of Sir Ed Hillary show him using a Bowline as a tie-in knot (Note: Crucially - or luckily - they used hawser lay vegetable fibre rope in those days which had a rough/frictive exterior - and that property of the rope likely saved many climbers from catastrophic knot failure). These days of course, we use synthetic fibre ropes of a Kernmantel (German spelling) construction - its slick and slippery and a Bowline in its standard form (#1010) will not be secure and stable.

Hence, sensible/informed climbers who choose to use a Bowline will take counter-measures to secure the #1010 structure in some way.

I personally always use the EBSB Bowline variant - and have done for several years now - and have tested the EBSB structure in real-world circumstances (I'm a climber). As I am typing this post, it is evident that I am still alive  - so therefore the EBSB variant has proven capability and is fit for purpose. NOTE: Others use the EBSB too - I'm not alone. I am what is loosely known as a 'trad' climber. I like to 'on-sight' new routes by climbing them ground-up without prior rehearsals or inspections. I lead the new routes using removable protection devices. I risk taking BIG falls - and the tie-in know of choice for me is the EBSB. Indeed, I have taken several significant leader falls and the EBSB did not fail, or become unstable or insecure in any way. I like it because the tail is held firmly in 2 places and, being as Bowline derivative, it is easy to untie after high loading events.

The EBSB variant was inspired by Dan Lehman's EBDB creation.

...

Having said all that, I would be VERY interested to learn more about Mobius creation.

Quote
I am quite keen to do my own trials on it first before releasing it her for critique (ridicule perhaps  :P ). My trials might only go as far as seeing if the knot collapses under strain (something a lot more than me just tugging on the knot furiously with all my might ;) ) and if it is easy to untie after load. If the knot looks promising to me I'll share it with the forum.

I would like to include it in my next update of the Bowline Analysis document. In that document, I will also be adding information about knot terminology with clear photos illustrating the terms (ie turn/loop/strangle/slipped/underhand/overhand/ etc...).

Also hoping to enlist Dan Lehman and Xarax and anyone else that can assist because my ambition is to make it the definitive resource on the Bowline for all to use in the public domain. You might say that it is on my bucket list of things to do before I die to get the Bowline Analysis document as close to perfect as I can (if such a goal is indeed even possible!).

Mark



« Last Edit: April 13, 2015, 01:03:53 PM by agent_smith »

xarax

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #18 on: April 13, 2015, 01:23:35 PM »
As I am typing this post, it is evident that I am still alive

   :) :) :)

... my ambition is to make it the definitive resource on the Bowline for all to use in the public domain. You might say that it is on my bucket list of things to do before I die to get the Bowline Analysis document as close to perfect as I can (

  Please, do it before I, too, die !  :) :) :) If you continue at the present pace, I will be forced to live for centuries !  :)
This is not a knot.

Mobius

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #19 on: April 13, 2015, 03:52:04 PM »
The EBSB variant was inspired by Dan Lehman's EBDB creation.

...

Having said all that, I would be VERY interested to learn more about Mobius creation.

Mark

Another knot (2 nipping turns, 2 collars): I also have a "Dan Lehman's EBDB style bowline (with an extra 'yobo' tuck, Dan will love that aspect I'm sure :) ). I came upon this knot independently (and it is not just a re-tucked EBDB) that is PET and TIB. The trouble with this particular knot is that the tie method for TIB sucks IMHO. Perhaps it is just me, however if I have to mentally struggle to remember to twist numerous times in the right direction, create a loop, or two (in the appropriate helix structure), pass a bight through a loop structure with the right twist, it is simply all too hard to bother with (even when the knot can be laid out flat in front of me).

The first knot I mentioned previously doesn't suffer from that defect I believe. It is more complex on one level since it has more structure (2 nipping turns and 3 collars), however it is very easy to tie TIB.

Anyway, thanks for your supporting comments Mark. I'm now spurred on to test my knot(s) further :)

Cheers,

mobius

Mobius

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #20 on: April 14, 2015, 07:08:49 AM »
  Do you really believe that the method of tying the Girth hitch-based TIB bowline involves "nefarious" twists ?  :) :)

That knot is easy to tie TIB in 2-dimesions, that is obvious from the given pictures. Unfortunately, what is not obvious is how one is supposed to tie it in an easy manner when the comfort of a flat surface is not available to set out our knot as shown. Eg. when we are 10m up, leaning against a ladder while standing on one of it's rungs. Equally unfortunate is that several TIB knot tying methods shown on this forum, or other sites, seem to rely on a flat working surface to make them work! Also, even with the benefit of a flat working surface some of them are full of nefarious twists ;)

Now for the good news, the Girth hitch-based Bowline can be tied in a nice manner in 4 main steps without any surface to work on, but xarax probably knew that already :) So the knot appears to be a very good one: PET, TIB, easy to tie.... and no.... it does not require nefarious twists when tied in the TIB fashion I used.

BTW, I prefer the version of this knot where the eye is reeved through the collar in the opposite direction. The knot you end up with is one where the two nipping loops seem to stay together and the knot seems to snug better. Maybe a matter of taste.
« Last Edit: April 14, 2015, 11:38:11 AM by mobius »

xarax

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #21 on: April 14, 2015, 02:54:01 PM »
  There is something "in" the object we call a "knot" per se, which contributes to the easiness we can handle it mentally, in our mind s 2D "screen" : the representation and the transformation of knots becomes very simple and unambiguous, when the knot is spread out in a 2D real or imaginary "flat surface", and all crossing points are crossing points of two, and two only, lines. The same happens in mathematical knots : To represent their knots, mathematicians use "flat" diagrams, where all crossing points correspond to two, and two only, overlapping lines at each point, although their "lines" are supposed to be infinitely stretchable, and they could had used any "curved" and tangled representation they had wished. 
   So, it seems that there is something "in the knots", or, at least, "in our mind", which makes us represent the loose knots on a 2D surface, that is, as been "flattened out". Of course, a finished 3D knot can be loosened and then squeezed on any 2D flat surface we wish, there is no "preferable", intrinsically determined orientation to do this. However, there will always be one orientation from which a projection of the compact 3D knot on a 2D surface will have a maximal area cross section, and one from which such a projection will have a minimal area cross section. From this one orientation the knot will look more "flat", and from the other one it will look more "globular". We chose to select the former and call the view from it "front" or "rear" , and prefer to represent the loosened or the compact knots in this orientation, simply because when the cross section becomes larger, the distance between any two crossing points become larger, too, and the possibility to have "ambiguous" crossing points with three or more lines overlapping each other becomes smaller.
   This means that our choice of the "flat" "front/back" view is not as arbitrary as one might think it is... There are some knots where, initially, it is arbitrary, indeed, when the knot is axially symmetric - as the beautiful Diamond bend and PET loop is, for example :                                       
   http://igkt.net/sm/index.php?topic=5151.0
   However, if we chose to project the pair of the Standing/Tail Ends so that the two lines do not overlap each other, they are not "over" or "under" each other, but "side by side", the one next to the other, we get a preferred orientation for those knots, too ( see the attached picture ).
   http://igkt.net/sm/index.php?topic=5151.msg33744#msg33744

   In short, all knots, in their loose or their most compact form(s), can be represented on one more or less preferable "flat" surface, and the fact that such a surface may not be actually/physically available, "at hand", does not mean that it can not be mentally available, in "the mind s eye". It is this surface which helps us remember and manipulate the knots, more than anything else. When a climber ties and unties a knot, he should be able to do this when he wears gloves, and his ropes and fingers are almost frozen, and in the dark, and hung upside down, and behind his back !  :) :) There is no flat surface anywhere close - but there is always a flat representation of those knots in his mind, without which he can do nothing at all. See all representations of the fig.8 knot : they are flat, and moreover they are flattened by been spread out on a surface of always the same orientation, although the fig.7 knot is a complex convoluted 3D shape, which could had been viewed from any angle. Do you always carry this 2D surface in your brain s luggage ? Then do not be afraid of the absence of the table you forgot at home...  :)   
« Last Edit: May 18, 2015, 04:03:02 AM by xarax »
This is not a knot.

Tex

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #22 on: April 14, 2015, 03:46:14 PM »

I started this post to say that I love how the retraced bowline tied PET or TIB (I'm picking up the lingo here) is beautifully easy to verify.  Even if you've never seen one before you can tell in an instant that it's not tied wrong.

It's pretty easy to tie (if tedious) to tie and you can even do it one handed.

Obviously as pointed out, it's inefficient, especially if you need a large loop, and under pure ring loading with standing ends loose, it seems still like the wrong knot to me.

Do you guys who like testing knots by tying them to your waist and falling off rocks trust it? (Only answer if you're still alive)

I don't love fixing basic bowlines or crazy variations of bowlines because there are so many crazy fixes out there and many aren't so beautifully obvious and the Yosimite even seems at least as scary as no fix at all. 

... but then I saw that girth hitch bowline and I have to say it's kind of neat, and yes, easy to tie, even if not quite as easy to verify. 






 

Tex

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #23 on: April 15, 2015, 03:19:51 AM »
It seems I wasn't clear.  I meant this:
http://www.animatedknots.com/bowlinebight/

So there are three differences between that and xarax's girth hitch bowline.

1) the girth hitch instead of the half-hitch nip
2) using 1 side of thee loop to tie the hitch instead of both sides (I'll call this one sided vs two sided)
3) and this not exactly topological but possibly very important, pulling one of the two main loops up tight into the knot which the girth hitch as shown does and the one in the link doesn't which is why one has a single main loop and the other a double.   (I'll call this single or double looped)
   
What's neat is you can apply, independently any combination of the 3 differences.

-A one sided single looped half hitch version becomes a slip knot, and the double looped one is messed up because it's like a slip knot and a bowline side by side.

-however a two sided single looped half hitch version  (so the one in the link put pulling in one of the main loops)  seems to me pretty ring-load resistant, but just initial feeling.

-a two sided girth hitch seems pretty fine on initial impression, maybe regardless of single or double looped.

I haven't played with them much.




Tex

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #24 on: April 15, 2015, 03:53:23 AM »
I messed that up a little. 

Either of the single sided double loop combos make a slip knot plus a bowline.  In either case if you pull up the slip side you're back to a single sided single loop version for both hitch styles.  But that pulled up loop maybe isn't buying you much for ring loading because it slips straight through to one of the tails.  It's not hurting either though.

The pulled up loop maybe only buys you extra in the double sided versions, where it then makes an extra nip that's tugged by the other loop.

Anyway the double looped versions only make sense for the double sided nips.


(edit: So apparently I didn't understand PET, oh well)
« Last Edit: April 15, 2015, 05:42:33 AM by Tex »

Tex

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #25 on: April 15, 2015, 05:54:46 AM »
and not surprisingly xarax and others have been over this stuff before:

http://igkt.net/sm/index.php?topic=4687.0

.. and to me it all comes back to the visual clarity of the retraced bowline.

xarax

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #26 on: April 15, 2015, 10:19:51 AM »
   The bowline in, on or upon the bight is a beauty, no question about that. The "clarity of the retraced bowline", as you describe the simplicity of its form and method of tying it in-the-end, AND the "haltering/haltered collar" method of tying it in-the-bight ( ABoK#1080), make it one of the great knots we have.
   ( Now there is a vacant seat in my pantheon of "old" knots (1), I wonder if I should offer it to this double loop, which can easily be transformed into a secure single TIB bowline that can be loaded by both ends, or by any of its ends, as you say... :) )

1.  http://igkt.net/sm/index.php?topic=1150.msg33735#msg33735
« Last Edit: April 15, 2015, 10:20:32 AM by xarax »
This is not a knot.

Mobius

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #27 on: April 15, 2015, 10:29:19 AM »
...when the comfort of a flat surface is not available to set out our knot.

  I have a "lines filling", by "keystroking"  :), comment on this : The "flat surface" is not required for our hands and fingers, to actually help us manipulate the ropes, but for our mind, to help us visualize and memorize the form of the loose and/or the compact knot and the sequence of the required tying moves - and, fortunately, our mind has evolved in a way that made it extremely capable to do this....

Yet again, another thoughtful response to one of my posts, thank you xarax :)

I don't think my knotting mind 'evolution' has taken place yet ;) Some 2-dimensional diagrams are fine for helping us tie in the 3D world, others are simply not. For example, I recently learned to tie the Double Dragon. A 2D representation of the knot given just prior to the final collar tuck is fine for me as a tying method. I believe it translates well from 2D to 3D.

Now let's consider the 'b' 'q' method of tying a Zepplin bend. In 2D world it is easy (I am referring to using a table to lay the knot out on), in 3D world the forming of the knot is a little more awkward: ie. Make the correct helix 'b', hold on to it while nipping the other reverse helix 'q' into the right place. Then pass the ends through the loops in opposite directions. I don't even think this knot is particularly hard to do 'in the hand' with this same method, however I am sure it is already past the capabilities of many people who tie knots just occasionally.

Now for a method that has been labeled as "easy" in 2D world and the reality is that the best way to tie the knot 3D bears little more than a passing resemblance to the 2D depiction of it. On top of that, one is left trying to find a reasonable tying method and thinking to oneself, "I must be stupid, this isn't easy"  ;D

It is this surface which helps us remember and manipulate the knots, more than anything else. When a climber ties and unties a knot, he should be able to do this when he wears gloves, and his ropes and fingers are almost frozen, and in the dark, and hung upside down, and behind his back !  :) :) There is no flat surface anywhere close - but there is always a flat representation of those knots in his mind, without which he can do nothing at all. 

I could not disagree more. I am not a climber, however the last thing I would think about (if I was tying a knot on some mountain side) would be what the 2D knot looked like (ie. one laid out on a table top). What I would be thinking about is the steps I have practiced to hold the knot properly in my hands and do the appropriate turns and tucks. These two approaches are quite different I believe. As a personal and hopefully somewhat relevant example: I recently started playing with string (rope) again and realized that the children's knot shapes (teacups, rocket ships, etc) I thought I had long forgotten were still there, "in my hands". What helps us remember knots is not a 'surface', it is manual dexterity and practice. I believe our hands can 'remember' things we didn't even know we knew  8)

Please do not think I am belittling anyones usually fine efforts at showing us (the forum) one-off tying diagrams. Some do exactly what they are supposed to, show us how to tie the knot in 3D and that is because those images happen to translate well. Other images, simply do not translate well into 3D for me; unless I grow an extra hand perhaps ;)

Cheers,

mobius

[edit: changed the mistyped 'p' to 'q' ... that, strangely enough, is also a common tying problem I believe]
« Last Edit: April 15, 2015, 02:59:16 PM by mobius »

Mobius

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #28 on: April 15, 2015, 01:25:54 PM »
BTW, I prefer the version of this knot where the eye is reeved through the collar in the opposite direction.
...Maybe a matter of taste.

  Now you have raised the bar, and demand a TIB loop which should be able to be loaded by both ends, or by any one of them, we, too, should pay attention to reeve the bight ( which is to be "haltered", and become a collar ) through the direction which leads to suitable such loops - that is, loops where both ends leave their nubs towards the same side, "upwards".

Yes, the pictures xarax shows later are the version I liked. Note that the nipping loops are shown apart (for picture clarity) though they snug together quite nicely with a little dressing.

xarax

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #29 on: April 15, 2015, 01:57:52 PM »
   Another, more "knotted" Pretzel base - which also looks like the real pretzels !  :)
   It can be tied by the same "haltering/haltered collar method" as easily as the other one - only you have to use some more "nefarious" twists  :) (1). I am not sure if this more convoluted / complex nipping structure grips the penetrating lines more effectively. I believe that some complexity may be beneficial, in order  to obtain an intergraded, compact nub, but we should always be very cautious to avoid the overkill, and be left with redundant segments encircling other segments, and sheltering/protecting, instead of squeezing, the penetrating leg(s) of the collar(s).

1. http://igkt.net/sm/index.php?topic=4464.msg33112#msg33112
« Last Edit: May 18, 2015, 02:58:45 AM by xarax »
This is not a knot.