Author Topic: How to improve the security of the bowline. Two simple instructions.  (Read 13536 times)

xarax

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   The somewhat naive definition of the bowline, as an end-of-line fixed loop based upon two elements, a simple or complex TIB nipping loop on the standing end, (before the tip of the bight), and a simple or complex collar on the working end, (after the tip of bight), has an additional  advantage :  It helps us paint a simple mental picture of this knot, that can be easily improved in a straightforward way : So, if we wish to improve the security of the (common or Eskimo) bowline, we can
1), just add more elements on top of the already existing ones, or we can
2), replace the simple (original) elements by more complex/convoluted (modified) ones.

1.  Tie more than one simple nipping loops, and/or more than one simple/"proper" collars. This is the easier and more obvious way to improve the security of the common and the Eskimo bowlines : you just do the same thing you have already done, at the same or at another part of the knot.
   a). The additional nipping loops can be tied in any of the three tensioned limbs of the bowline: the standing end, the eye leg of the standing part ( before the tip of the bight) and the eye leg of the bight (after the tip of the bight). ( See, for example, the Water bowline, or the Ice bowline (1).)
   b). The additional collars can be tied by a working end that exits the nipping loop, makes a U turn around any of those three limbs, and returns into the same nipping loop. ( See, for example, the Janus (A, B, C) bowlines (7), (2).)

2. Tie more complex types of nipping loops, and/or more complex types of collars.
   a). The more complex/convoluted nipping loops can be TIB (tied in the bight) structures that are tied on a tensioned limb, in an effort to increase the contact area between the nipping loop and the working end/tail that passes through it. ( See, for example the Double bowline, the Double crossed-coils bowline (3), the Girth hitch bowline (7), the Constrictor bowline (4), or the Pretzel bowline (5).)
   b). The more complex/convoluted collars can be a double or triple collar, or a combination of a "proper" bowline collar with a Myrtle collar around a segment of a tensioned limb, or even around a segment of the nipping loop. ( See, for example, the Yosemite bowline (7), the EBSB and EBDB bowlines (7), or the SS369 bowline (6).)

1.   http://igkt.net/sm/index.php?topic=1929.0
2.   http://igkt.net/sm/index.php?topic=1202.msg19317#msg19317
3.   http://igkt.net/sm/index.php?topic=3550.msg20220#msg20220
4.   http://igkt.net/sm/index.php?topic=3150.0
5.   http://igkt.net/sm/index.php?topic=1940.0
6.   http://igkt.net/sm/index.php?topic=19.msg20538#msg20538
7.   http://www.paci.com.au/downloads_public/knots/02_Bowlines.pdf
« Last Edit: September 13, 2011, 01:07:59 PM by xarax »
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Mobius

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #1 on: April 04, 2015, 06:15:01 AM »
(Hmm... a site warning tells me this thread is 'old' and I should consider posting elsewhere. For better, or worse (ie a waste of my time  ;) ), I have posted here).

I am interested in developing a secure bowline that is TIB and is very easy to tie in both a PET (end loop) fashion and is also able to be used (practically) as a secure mid line loop. With particular regard to being TIB, I believe for such a bowline to be considered 'useful' it would need to be as secure (if not more so) than an Alpine Butterfly Loop and as quick and easy to tie in the bight (or at least nearly so). For all practical purposes, I do not see a mountaineer even considering a bowline as a fixed mid line loop unless it is very easy to tie reliably, is able to be ring loaded,  and has been tested as offering security in suitable climbing type ropes.

With the above in mind, perhaps the "Two simple instructions" should be broadened to include; 3) easy and reliable tying methods in both PET and TIB forms, and; 4) able to resist ring loading.

I realize that a bowline that does all these things is a rare beast indeed (not discovered yet as far as I know).

Note that I am discounting any known bowline that is 'supposedly' TIB, but is nearly impossible to tie reliably from a practical perspective. I am making a distinction between a theoretical TIB bowline and a practical TIB bowline. This latter point is relevant I think as I am sure I am not alone in having tried to de-construct a relatively basic bowline that, designed initially as an end of loop knot, just happens to be TIB. In many such bowlines, I have often encountered that it is VERY easy to make one wrong twist/turn when trying to tie them in the bight to only end up with a 'slip knot' style bowline or, worse still, one that just falls apart altogether! If someone is hanging off the side of a mountain, in the cold and rain, the knot chosen better be secure and easy for them to tie. Otherwise, forget it. For this reason, there are probably many so-called TIB bowlines that should be in the 'forget' category from a practical standpoint I believe.

Cheers,

mobius

[changed which for that]
« Last Edit: April 06, 2015, 10:41:23 AM by mobius »

Twine

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #2 on: April 04, 2015, 12:42:58 PM »
I am interested in developing a secure bowline which is TIB and is very easy to tie in both a PET (end loop) fashion and is also able to be used (practically) as a secure mid line loop. With particular regard to being TIB, I believe for such a bowline to be considered 'useful' it would need to be as secure (if not more so) than an Alpine Butterfly Loop and as quick and easy to tie in the bight (or at least nearly so). For all practical purposes, I do not see a mountaineer even considering a bowline as a fixed mid line loop unless it is very easy to tie reliably, is able to be ring loaded,  and has been tested as offering security in suitable climbing type ropes.

The Double Dragon loop does all that, but I'm not sure if it's really a bowline. Also, I'm not sure how thoroughly it has been tested.

Instructions for how to tie it can be found at http://www.southee.com/Knots/Knots_SingleLoops.htm

/Twine
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xarax

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #3 on: April 04, 2015, 12:55:54 PM »
   The Double Dragon loop does all that

  Indeed, the Double Dragon loop should also be mentioned and compared to the other TIB PET loops. About my opinion on this knot, see :
   http://igkt.net/sm/index.php?topic=4919.msg32215#msg32215
   The above cited thread contains information about other TIB loops, too.
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Twine

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #4 on: April 04, 2015, 02:42:20 PM »
I'm glad you agree, Xarax. I read the thread you linked to, and it was interesting to read your thoughts about the dressing of the Double Dragon loop. I had not given that much thought before, but after some consideration, I now think that the correct way to dress it is the one where the turn encircling the standing part is the widest, simply because wider turns in a knot contribute less to wear, even in ropes that are strong enough to withstand breaking even if they are tied with knots with sharper turns in them. Luckily, this is the form of dressing that usually forms spontaneously in the Double Dragon loop. I've never seen the other form except when I deliberately deform the knot.
"Simplicity is the ultimate sophistication" - Leonardo da Vinci

roo

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #5 on: April 04, 2015, 04:59:24 PM »
I am interested in developing a secure bowline which is TIB and is very easy to tie in both a PET (end loop) fashion and is also able to be used (practically) as a secure mid line loop. With particular regard to being TIB, I believe for such a bowline to be considered 'useful' it would need to be as secure (if not more so) than an Alpine Butterfly Loop and as quick and easy to tie in the bight (or at least nearly so). For all practical purposes, I do not see a mountaineer even considering a bowline as a fixed mid line loop unless it is very easy to tie reliably, is able to be ring loaded,  and has been tested as offering security in suitable climbing type ropes.

The Double Dragon loop does all that, but I'm not sure if it's really a bowline. Also, I'm not sure how thoroughly it has been tested.

Instructions for how to tie it can be found at http://www.southee.com/Knots/Knots_SingleLoops.htm

/Twine
It's been discussed before.  It is jam prone as a midline loop when the parent line is under tension, or when tied as a bend as Dave Root has depicted on his site. The Double Dragon Midline Loop variant doesn't seem to be jam prone when the loop is loaded and either the standing part is pulled by itself or when the loop is loaded and what is usually the free end is pulled by itself.

In other words, the midline variant is OK when pulled on from one side only, which is very limiting.

I was doing some shake testing of the double dragon loop with some Bluewater II, and found that it popped open and untied much earlier than I'd prefer when compared with other similar size or complexity loops. 

There are a few ways of tying the double dragon loop, but the simple way has a fundamental problem in that you cannot thread the rope around or through an object before closing.  That's somewhat important for an end loop.

In summary, this is a poster child for why you should not try to limit yourself to one knot.  In trying to cram multiple applications into one knot, you get something that is lacking in nearly all aspects.  Learn the language of knots, not just one or two words.

P.S.  The reason security requirements for midline loops are typically lower than end loops is that you're typically far away from the ends of the rope in a midline application with the added benefit of all the weight of those long ends.

« Last Edit: April 04, 2015, 05:00:52 PM by roo »
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Twine

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #6 on: April 05, 2015, 12:06:01 AM »

It's been discussed before.  It is jam prone as a midline loop when the parent line is under tension, or when tied as a bend as Dave Root has depicted on his site. The Double Dragon Midline Loop variant doesn't seem to be jam prone when the loop is loaded and either the standing part is pulled by itself or when the loop is loaded and what is usually the free end is pulled by itself.

In other words, the midline variant is OK when pulled on from one side only, which is very limiting.

I was doing some shake testing of the double dragon loop with some Bluewater II, and found that it popped open and untied much earlier than I'd prefer when compared with other similar size or complexity loops. 

There are a few ways of tying the double dragon loop, but the simple way has a fundamental problem in that you cannot thread the rope around or through an object before closing.  That's somewhat important for an end loop.

In summary, this is a poster child for why you should not try to limit yourself to one knot.  In trying to cram multiple applications into one knot, you get something that is lacking in nearly all aspects.  Learn the language of knots, not just one or two words.

P.S.  The reason security requirements for midline loops are typically lower than end loops is that you're typically far away from the ends of the rope in a midline application with the added benefit of all the weight of those long ends.

I can't argue with what you say, it's all true. Personally, I think the best is to use the Butterfly Loop for a midline loop and a double-knotted bowline (which I like to start like a double overhand noose and finish by tucking the tail through the collar) as a PET end loop. But those are two knots, so that wouldn't satisfy Mobius' specific request for one and the same knot, (which also must be a TIB bowline) for all purposes. I've never used the Double Dragon as a midline loop, except as idle experiment, so I didn't know it could jam in the circumstances you describe, but on the other hand, Mobius didn't specify non-jamming or ease of untying for his ideal knot.

Do you think Mobius or anyone will ever be able to find a single knot that fulfills all his specifications if we also include non-jamming and ease of untying in the specs? I'm pretty sure no such knot exists right now, because if it did, everyone would be using it.

A question about your shake test: the Bluewater II line, is it very springy and slippery?

/Twine
"Simplicity is the ultimate sophistication" - Leonardo da Vinci

xarax

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #7 on: April 05, 2015, 12:47:46 AM »
   I'm pretty sure no such knot exists right now,

  Do not !  :) :)

...because if it did, everyone would be using it.

  And, please, do not use THAT "proof" ! !  :) :)
  Knot tyers do not use the best knots, they use the knots they had learnt when they were still young enough and were able to memorize things, even if they did not understand them  :), or they use only the knots themselves had "invented". In any case, they are notoriously consistent in their greatest knotting principle : they do not tie other people s knots !  :) :) :)   
« Last Edit: April 05, 2015, 12:48:35 AM by xarax »
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Mobius

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #8 on: April 05, 2015, 03:20:16 AM »
.....
I've never used the Double Dragon as a midline loop, except as idle experiment, so I didn't know it could jam in the circumstances you describe, but on the other hand, Mobius didn't specify non-jamming or ease of untying for his ideal knot.

Do you think Mobius or anyone will ever be able to find a single knot that fulfills all his specifications if we also include non-jamming and ease of untying in the specs? I'm pretty sure no such knot exists right now, because if it did, everyone would be using it.
.....
/Twine

The first post was about security, so I stuck to that theme. However, I certainly would like to come up with a knot that is non-jamming, easy to untie, as well as everything else I described. I could also add to all the above that the tail should be able to be loaded securely along with, or instead of, the standing part. Tying a TIB loop that cannot be loaded on both ends, as well as the loop (perhaps individually), could be a big security issue, so end loading flexibility is a requirement.  I don't want much from a knot, do I :)

As a class of knots I was under impression that bowlines are typically non-jamming and easy to untie.The collar structure of many bowlines certainly helps in the latter untying aspect while the nature of the nipping turns (in particular) probably goes along way towards the knot jamming, or not. Along with potential strength and security, the supposed ease of untying and non-jamming is why people are so interested in bowlines, is it not?

The Double Dragon is certainly a nice knot, I like many aspects of it. Thank you for sharing.

Mobius

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #9 on: April 05, 2015, 06:51:50 AM »
... bowlines are typically non-jamming and easy to untie. The collar structure of many bowlines certainly helps in the latter untying aspect, while the nature of the nipping turns (in particular) probably goes along way towards the knot jamming, or not.

  It is the other way around !  :) The nipping turns make the bowlines easy to untie, and the collar structures ( well, some collar structures, combined with additional nipping turns ...) probably goes towards the knots jamming.
  ( See : http://igkt.net/sm/index.php?topic=4851.0 )

  P.S. There are some exceptions to this : The Clove- or the Constrictor-based double bowlines ( where the nipping structure is a Clove hitch or a Constrictor binding knot ), may jam, indeed - or, at least, become very difficult to untie.

Another new thing to consider :)

The top collar is where I typically start loosening a bowline to untie and the knot tends to come undone easily after that. At least that is true for the bowlines I have been playing with. Maybe I just have not been able to load them sufficiently for them to jam ;) The clove Hitch based nipping structure was the one I was thinking of probably being a problem, though a Constrictor base would likely be a problem too.

All very interesting to consider and perhaps a big balancing act is required between enough nip turns and collars to make a knot secure in all it's loading facets vs too many nip turns and collars (or ill conceived ones) that might cause the knot to jam.

Dan_Lehman

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #10 on: April 05, 2015, 09:11:24 PM »
[S-] I am interested in developing a secure bowline [that] is TIB
[P-] and is very easy to tie in both a PET (end loop) fashion and
[M-] is also able to be used (practically) as a secure mid line loop.
Here we should question the goal of putting all of these desiderata
into one knot.  There is some educated suspicion that doing so
will yield only somewhat material-inefficient and complicated knots,
in contrast to having two (or three) knots not so; that learning to
apply such a complicated knot will be more of a challenge than to
learn the multiple of knots each suited for a specific goal; that having
a different (TIB vs. PET) tying method might as well yield distinct
knots --there is no practical *prize* for getting the same!
(Your closing remarks acknowledge this situation.)

Quote
With particular regard to being TIB, I believe for such a bowline to be considered 'useful'
it would need to be as secure (if not more so) than an Alpine Butterfly Loop
and as quick and easy to tie in the bight (or at least nearly so).
For all practical purposes, I do not see a mountaineer even considering a bowline
as a fixed mid line loop unless it is very easy to tie reliably, is able to be ring loaded,
and has been tested as offering security in suitable climbing type ropes.

While it's a nice quality, what vulnerability do you foresee of
eyeknots NOT stable in ring-loading for mid-line eyes?
(The butterfly might be able to capsize, though if so, it will
likely be into a differently oriented butterfly --i.e., where the
eye legs become as S.Parts were, and vice versa.  (Other of similar
knots --viz., Ashley's bends #1408, 1452-- have this property.)

As for tested as offering security ... , where has that been done
(other than presumed "testing" by usage, or by break tests re
slippage during that one-time heavy loading) ?


--dl*
====

Mobius

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #11 on: April 06, 2015, 12:55:21 AM »
[S-] I am interested in developing a secure bowline [that] is TIB
[P-] and is very easy to tie in both a PET (end loop) fashion and
[M-] is also able to be used (practically) as a secure mid line loop.
Here we should question the goal of putting all of these desiderata
into one knot.  There is some educated suspicion that doing so
will yield only somewhat material-inefficient and complicated knots,
in contrast to having two (or three) knots not so;

Yes, it also occurs to me that a knot that tries to 'do it all' could easily end up being over-complicated to the point very few could reliably tie it, particularly the TIB bowline forms from my limited experience. I imagine that material inefficiency would not put too many off a knot, however difficult tie-ability certainly would. With particular regard to bowlines: I have noticed from my knot playing, that the PM knots that I have found an easy way to end loop tie are very difficult to tie mid line while the opposite can also be true! I am hoping to find one that is easy to tie mid line and not too bad to get right as an end loop, I think that is an easier objective than the other way around.

Quote
..... that learning to
apply such a complicated knot will be more of a challenge than to
learn the multiple of knots each suited for a specific goal; that having
a different (TIB vs. PET) tying method might as well yield distinct
knots --there is no practical *prize* for getting the same!
(Your closing remarks acknowledge this situation.)

Quote
With particular regard to being TIB, I believe for such a bowline to be considered 'useful'
it would need to be as secure (if not more so) than an Alpine Butterfly Loop
and as quick and easy to tie in the bight (or at least nearly so).
For all practical purposes, I do not see a mountaineer even considering a bowline
as a fixed mid line loop unless it is very easy to tie reliably, is able to be ring loaded,
and has been tested as offering security in suitable climbing type ropes.

While it's a nice quality, what vulnerability do you foresee of
eyeknots NOT stable in ring-loading for mid-line eyes?

I had read (Mark Gommers, 'An Analysis of Bowlines' is one such place) that the basic R-hand bowline is susceptible to ring loading while a Cowboy bowline is resistant to ring loading. This left me with the impression that ring loading was something a bowline should aim for in some applications. I do not see a particular vulnerability, and perhaps because TIB bowlines are more complex than a R-hand bowline, there is nothing to worry about. However, that isn't obvious to me. I would like to test any bowline I came up with for ring loading, just in case.

(The butterfly might be able to capsize, though if so, it will
likely be into a differently oriented butterfly --i.e., where the
eye legs become as S.Parts were, and vice versa.  (Other of similar
knots --viz., Ashley's bends #1408, 1452-- have this property.)

As for tested as offering security ... , where has that been done
(other than presumed "testing" by usage, or by break tests re
slippage during that one-time heavy loading) ?


--dl*
====

"Testing" by usage is the ultimate test, however I would not presume someone first testing any knot that I came up with by jumping off a cliff in a harness to see if it held :) Break tests under slow loads for slippage is certainly a good start, one-time heavy loading is important too. I don't have suitable test facilities to do these things unfortunately. Indeed, many good knots by others probably go relatively unnoticed since nobody has the time (or resources) to facility test them.

For someone with the resources to test a knot I think the knot would have to offer something worthwhile. Either the proposed knot will meet a very specific need, or the knot is a more general purpose 'one size fits all' that is very easy to tie and untie. One of those two things might prompt someone who does have the facilities to test a new knot.

Cheers,

mobius

[my first paragraph is an edit]
« Last Edit: April 06, 2015, 05:45:32 AM by mobius »

xarax

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #12 on: April 06, 2015, 04:10:03 AM »
  There is some educated suspicion ...

..."educated" suspicion (sic)...
   I try not to start laughing right from the start, because I am afraid I will not make it to the end - alive !  :) :) :)

...material-inefficient and complicated knots......

   The TIB Ampersand bowline, for example, which requires the same amount of material, and the same number of tucks, with any Janus bowline, is, according to Dan Lehman s educated guess, "material-inefficient" and "complicated".
   The same happens with the TIB Pet loop, which requires the same amount of material and the same number of tucks with the Span loop.
   The same happens with the TIB Pretzel loop, which requires less material, and fewer tucks, than his mediocre "quick8" - which does nt seem very TIB to me...
   I could easily go on and on, and compare the "material efficiency" and the tying complexity of those knots with Dan Lehman s "Mirrored bowline", or his two TIB Zeppelin-like loops - the one he did publish, and the other he promised to publish, as soon as my growing beard reaches the floor...
   In sort, TIB bowlines are sour grapes for some knot tyers who had not educated themselves on this subject - and, to blur the issue, they keep singing the same old song again and again, about "multiple knots, each suited for a specific goal"... Yeah, by definition there is an infinite number of specific things, in general, and "specific goals", in particular, and so there is an infinite number of knots suitable for them - so, when one wants to tie something, he should only ask the self-acclaimed "educated" gurus...   
   There ARE TIB bowlines which are as good as, or even better than, any other end-of-line loop - and I would even argue that we already have too many of them !  :)  In my previous posts, I had referred to some - the interested reader can search for them in this Forum and elsewhere, tie and try them - he will only need a piece of chord, and common sense ! Practical knotting is not rocket science, it is a subject no more difficult than arithmetic, for KnotGod s sake - it requires only patience, and, from one level and above, passion. However, I have to point out that a minimum portion of due reference to, and sincere evaluation of, what we already know, and of honesty as well, will make no harm... 
« Last Edit: April 06, 2015, 04:32:07 AM by xarax »
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Dan_Lehman

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #13 on: April 11, 2015, 06:14:02 PM »
[S-] I am interested in developing a secure bowline [that] is TIB
...
[M-] is also able to be used (practically) as a secure mid line loop.

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 don't think that X. has anything bowlinesque that will well
serve the latter need.  (But we can be certain that he can fill
many lines with keystrokes about "understanding" and blah!)

Quote
Quote
Quote
For all practical purposes, I do not see a mountaineer even considering a bowline
as a fixed mid line loop unless it is very easy to tie reliably, is able to be ring loaded,
and has been tested as offering security in suitable climbing type ropes.
While it's a nice quality, what vulnerability do you foresee of
eyeknots NOT stable in ring-loading for mid-line eyes?

I had read (Mark Gommers, 'An Analysis of Bowlines' is one such place)
that the basic R-hand bowline is susceptible to ring loading while a [so-called]
"Cowboy bowline" is resistant to ring loading. This left me with the impression
that ring loading was something a bowline should aim for in some applications.
I do not see a particular vulnerability, and perhaps because TIB bowlines are more
complex than a R-hand bowline, there is nothing to worry about. However, ...
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.  Perhaps this never occurred,
but one can test the problem and see that it exists --to some degree.
And it's an interesting counterpoint to the labeling of the tail-on-outside
version as being "wrong".  Otherwise, I observed this version in use
on a commercial-fishing trawler's mooring lines, and wondered if
perhaps that was a deliberate variation to the norm on account
of what I also observed (in the Cape May, New Jersey, USA area):
capsized bowlines !!  (I don't know why they get capsized,
but I have seen too many so oriented to dismiss it as insignificant!)

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*
====

xarax

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Re: How to improve the security of the bowline. Two simple instructions.
« Reply #14 on: April 11, 2015, 07:01:13 PM »
...something that can take all possible loadings
  I don't think that X. has anything bowlinesque that will well serve the latter need.

  I have not tested, or even tried as extensively as I would had wished, the TIB bowlines I know in that "reversed" kind of loading, that is true.
  However, as a great master of blah-blahing says ( when he imagines he has understood something ), an "educated suspicion"(sic)  :) tells me that there are such loops out there, which can be loaded like this, indeed - but as I had mentioned elsewhere, when they are loaded this way, they behave not as classic bowlines any more, but as crossing knot-based bowline-like loops. Crossing-knot-based PET loops have not attracted the attention they deserve, IMHO, so we just do not have enough information about them to predict their properties under heavy loading...
  Try the ones I propose, the Ampersand bowline and the Pet loop, and tell me what you see.
  The real master of the bowline-like knots we are lucky to have in our Forum, who is not talking/blah-blahing because he is doing, Alan Lee, has not only tied dozens of dozens secure, neat and very original such loops, but has tried some of them as well. Perhaps he can tell you more about this interesting issue.
« Last Edit: April 11, 2015, 07:05:03 PM by xarax »
This is not a knot.