Author Topic: Analysis of Bowlines paper uploaded for review and comment (PACI website)  (Read 108098 times)

SS369

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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.

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X1

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   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
2. http://bealplanet.com/sport/anglais/corde-procanyon.php
 
   
« Last Edit: July 28, 2013, 05:32:25 PM by X1 »

SS369

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   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
2. 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.  ;)


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X1

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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
   The "newer" TIB version is shown in previous posts, and in :
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
   ( just in case you have forgotten it... :) )
 
« Last Edit: July 28, 2013, 06:11:40 PM by X1 »

SS369

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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
   The "newer" TIB version is shown in previous posts, and in :
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
   ( 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.

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X1

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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 ?   
« Last Edit: July 29, 2013, 05:47:29 PM by X1 »

SS369

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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.  ;)


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agent_smith

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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

roo

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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.
« Last Edit: July 29, 2013, 05:17:18 PM by roo »
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X1

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   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... :)
   
 
 
« Last Edit: July 29, 2013, 05:44:11 PM by X1 »

roo

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   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!

Can you stay on topic, please?
« Last Edit: July 31, 2013, 02:54:26 PM by roo »
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X1

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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!

   "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.
2. http://en.wikipedia.org/wiki/Zeppelin_loop
« Last Edit: July 29, 2013, 07:53:24 PM by X1 »

roo

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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.
« Last Edit: July 29, 2013, 11:13:50 PM by roo »
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Dan_Lehman

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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*
====

agent_smith

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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