Author Topic: Adjustable Loops  (Read 48294 times)

roo

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Re: Load testing of various Bowline structures
« Reply #45 on: June 09, 2015, 09:06:44 PM »
- when you can not even divide 7663 by 1400...  :)
I can divide those numbers, but they're not part of the equation:
http://igkt.net/sm/index.php?topic=5383.msg36061#msg36061

Re-read slowly.  Look for "soft rope".
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alpineer

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Re: Load testing of various Bowline structures
« Reply #46 on: June 09, 2015, 09:28:16 PM »
Quote

Your honesty and integrity were never in doubt by me, SS.

Of course, all aspects of material nature - including dimensions - determine a knot's performance. But do they explain per se the use of pliers and spike to untie the knot in your case?
Thank you Alpineer for not doubting my honesty and integrity. That is what I will always strive for in evaluating an offering. I may be wrong, but I will be honest.  ;D

The use of the round nose pliers was needed for both those samples I tied due to small diameter ratios to finger size and materials. I can only suspect that if the loads were great enough on the larger diameter ropes the results would be accordingly similar. I have not tried them. I'll certainly take your report/results as honest at the loads you've subjected the knot to. NP.

SS

Thanks SS.
You might consider giving your same experiment a whirl with the nipping structure in Blood Knot - rather than Barrel Knot - configuration. Not sure if this will make any difference for you. 
« Last Edit: June 09, 2015, 09:41:54 PM by alpineer »

xarax

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Re: Load testing of various Bowline structures
« Reply #47 on: June 09, 2015, 09:31:04 PM »
   Look, using your glasses, the pictures of Alan Lee, at :
   http://igkt.net/sm/index.php?topic=4849.msg33147#msg33147
   I was talking about THIS post... Do you see any "soft" rope ? If yes, you "see" things... :) :) :)

   It would be more clever ( to put it politely, because I could well had used the antonyms of those two words...) for you, to start a campaign ( and, who knows, a possibly successful advertising ) of the Ashley s bend turned into a loop. It has exactly the same properties as your beloved frog-knot, and you will not be alone in this... ( I guess that your usual ally, Dan Lehman, will be more supportive of the Ashley s bend turned into a loop, than he is now for the Rosenthal loop... :) )

P.S. I do not know which of the two dressings of the Ashley s bend should be used, in order to tie a less prone to jamming eyeknot... I have not tested them in loads heavier than the "Working load" = 1/10 th of the MBS of the line !  :)
« Last Edit: June 09, 2015, 11:52:41 PM by xarax »
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roo

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Re: Load testing of various Bowline structures
« Reply #48 on: June 09, 2015, 09:40:04 PM »
   Look, using your glasses, the pictures of Alan Lee, at :
   http://igkt.net/sm/index.php?topic=4849.msg33147#msg33147
   I was talking about THIS post...
I quoted later on in that same thread where Alan revised his tests to get more accurate numbers and not just a rough guess.
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xarax

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Re: Load testing of various Bowline structures
« Reply #49 on: June 09, 2015, 09:58:54 PM »
Alan revised his tests to get more accurate numbers and not just a rough guess.

   You "see" things, indeed ! Would nt it better ( for all...) to have some sleep ?
   Alan Lee had not revised ANY numbers, and those in the post with the knots tied on the "soft" rope  :) :)  I had referred to were the only ones in this thread. In another post, he just told you the "Working load" of the ropes he used - which, for the not-imaginary soft rope, was the 1/10th of the MBS !
   You tried, desperately, to argue that, because the so-called "Zeppelin loop" could be untied ( we do not know with what difficulty...) after it was loaded with the 1/5th of the MBS, and because 1/5th is double the laughable 1/10th, your frog has been a disguised prince right from the start !
   All those years you are trying so hard to sell this frog-knot, you did nt know that, if you accept as "Working load" the 1/10th of the MBS, ANY interlocked overhand-knot-based bend turned into an eyeknot, and loaded so lightly, will be easy to untie ? You waited Alan Lee to told you that ?
   However, I believe that, simply, you had not thought of this trick back then... Now that your frog-knot has be revealed in all its smallness, you invented this tactic of the "Working-load-untiable" so-called "Zeppelin loop" eyeknot !  :)  :)  I think that the other Nobel-prize worth strategy, of Dan Lehman, with his "Dyneema-untiable" Lehman8 eyeknot, is "more clever".   
     
« Last Edit: June 09, 2015, 10:05:39 PM by xarax »
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roo

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Re: Load testing of various Bowline structures
« Reply #50 on: June 09, 2015, 10:24:32 PM »
   You "see" things, indeed ! Would nt it better ( for all...) to have some sleep ?
   Alan Lee had not revised ANY numbers, and those in the post with the knots tied on the "soft" rope  :) :)  I had referred to were the only ones in this thread. In another post, he just told you the "Working load" of the ropes he used - which, for the not-imaginary soft rope, was the 1/10th of the MBS !
   You tried, desperately, to argue that, because the so-called "Zeppelin loop" could be untied ( we do not know with what difficulty...) after it was loaded with the 1/5th of the MBS, and because 1/5th is double the laughable 1/10th, your frog has been a disguised prince right from the start !
   
You really need to slow down and re-read post several times before responding.  I assumed a harsher working load limit of 1/5 of the 3000 lb breaking load (working load limit = 600 lb) and Alan was able to untie things after applying twice this 600 lb (600 lb X 2 = 1200 lb) or 1/5 (not 1/10!) value.  Regardless of whether your misreading and/or misrepresentation of posts is accidental* or intentional, I give up. 

*Xarax's next clearly dishonest post talking about 1/10 & even 1/20 breaking loads cleared that up.
« Last Edit: June 11, 2015, 04:32:26 PM by roo »
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xarax

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Re: Load testing of various Bowline structures
« Reply #51 on: June 09, 2015, 10:59:30 PM »
I give up.
   
   Good !  :)  Go to sleep, now... Because the supposed "rough guess"(sic) was not where you had imagined you saw it...And because I was always talking about Alan Lee s numbers on not-soft ropes, shown in the post I had referred to MANY times, and where you had also imagined you have "seen" soft ropes. I was NOT talking about the test on the soft rope. I had said it dozens of times, that I am interested in climbing/industrial/rescue kernmantle ropes, not in fishing lines, easily-flattened ropes, elastic / bungee cords, etc. (  Now I have mentioned it, it may be a good idea to start promoting your frog-knot as a bungee-cord prince-knot !  I am sure that, on such a material, it will make a nice ball ! )
   
   Your not-so-clever, to say it politely, trick with the introduction of the 1/10th ( or even better, the 1/15, or the 1/20th ) of the MBS, as the maximum load with which we should load our ropes, to see if they are easy to untie or not, is only "bon pour l orient", I am afraid.. I made you a favour, and suggested to you two ways out of your obvious impasse : First, adopt another overhand-knot-based bend turned into loop, the Ashley s bend : Start selling the Ashley s loop ! That way, you will have an ally, Dan Lehman, and you will not have me revealing the frog-ness of the so-called "Zeppelin loop" to your clients... Second, adopt the Dyneema-inspired strategy of Dan Lehman : Start talking about how safe all those too-tight eyeknots are, when tied on Dyneema - that trick may save the a... even of your frog-knot !
« Last Edit: June 09, 2015, 11:05:40 PM by xarax »
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xarax

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Re: Load testing of various Bowline structures
« Reply #52 on: June 09, 2015, 11:34:11 PM »
  able to untie things after applying twice this 600 lb (600 lb X 2 = 1200 lb) or the 1/5th (not the 1/10th ! ) value. 

   A peasant was complaining to the local priest that his house was too small, the 1/5th of what he would had wished. The priest tells him to put the horse into the house. After a week, the peasant goes again to the priest, and starts complaining more. The priest tells him to put the cow into the house. After two days, the peasant goes again to the priest, and tells him that the situation has become unbearable, and that now he is forced to live in the half of the house, i.e., in a house which is the 1/10th of what he needs. The priest tells him to put the pig into the house. The very next day, the peasant is begging the priest to do something. Then, the priest tells him to put the horse, the cow and the pig out of the house again. In just one hour, the peasant returns to the priest, and tells him how happy he is he now lives in such a big house !
   That is the "bon pour l orient" trick attempted with the invention of the "Working-load-untiable" eyeknot ! We choose a low Working load, say, the 1/10th of the MBS. Then, if our eyeknot can be untied after it has been loaded with the 1/5th of the MBS, we feel happy:)
   
   KnotGod made so many good knots, but then he got tired, and when he made the knot-tyers, he cut some corners...   
« Last Edit: June 09, 2015, 11:35:48 PM by xarax »
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agent_smith

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Re: Load testing of various Bowline structures
« Reply #53 on: June 10, 2015, 01:36:35 AM »
Hello mobius,

When are you planning to commence testing your Bowline structures?

I need to know because I would like to use your data (with permission) in the 'Analysis of Bowlines and other selected Eye knots' paper.

Please advise....

Thanks, Mark G
« Last Edit: June 10, 2015, 01:37:40 AM by agent_smith »

Dan_Lehman

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Re: Load testing of various Bowline structures
« Reply #54 on: June 10, 2015, 04:35:28 AM »
   Heavy loading, in what material ? 

  What I use to all "heavy", I guess that it should be a significant percentage of the MBS of the knot, or even of the line - say, 25%, 33,3%, or 50%. We have to define what we mean by this term - and it would be great if we could establish some benchmark loading percentages, and test our ropes in all of them.
There are two senses here : that of the proportion to the
tensile strength; and that in proportion to manual strength.

In the first instance, note that the tightness of the structure
can differ widely per strength of the material, even though,
from one perspective, different materials present the same
sort of feel/size --but snap your fingers and magically convert
multifilament polypropylene into HMPE and suddenly that
force that was X% of tensile is now only X/5% or so(!!),
but the tightness is the same.

And otherwise, although Paul Bunyan (a mythical giant)
might find the knot tied in 1" line subjected to normal,
expected loads while mooring the trawler to be easily
untied, a mortal (wo)man might not.  YMMV.

Quote
  My own experience comes from kernmantle ropes, like those used in climbing, canyoning and rescue. I prefer them because they are stiff ( so they do not like sharp turns, and this makes me, too, to tie knots with wide, smooth curves ), they are not very compressible ( so they can not be flattened too much, and fill the voids in between the segments within the knot, turning it into a compact, massive and rigid ball which can not be un-knotted easily ), and they can retain an almost circular cross section ( so the contact area between two adjacent segments is not very extended ). I think that, in such material, the properties of the "knot" itself ( the geometry ) will manifest themselves more clearly, and the properties of the particular rope ( the material ) will play a secondary only role. I also tie knots in marine ropes, but I do not judge them by how they behave there - marine ropes are usually braided, and softer ( and less slippery ) than kernmantle ropes.
Hmmm, I've found that kernmantle ropes --exactly because
the kern (often) comprises individual cords not cohesive themselves,
hence needing the mantle, are (more) compressible given that these
individual cords can spread out within the mantle.  (To me, it makes
sense to define "kernmantle" to be a "rope with a core of separate
cords or fibres not cohesive as a whole themselves", though in the
past of such-named ropes are ones with braided (cohesive) kerns.)
But, yes, often, too, there is a lot of material packed into the
mantle, and the rope doesn't like to bend --notably, e.g., the
PMI caving rope and esp. older, used specimens of that (and
Bluewater II, a like rope)!

To say that "the properties of the "knot" itself ( the geometry )
will manifest themselves more clearly" is to betray some ideal
of *knot* too biased by a particular material.  Who's to say
that sharp turns are any less belonging to knotted material
than stiffly resisted broader ones?  Indeed, I can see someone
making just the opposite charge : that stiff ropes defeat allowing
a knot to achieve its truest manifestation (as might come from
some mathematical modeling algorithm, say)!

Which is why I've remarked that we'd do some justice in giving
caution and circumspection to others by referring to not the
qualities of some "*knot*" but to "*<this_material> so knotted*".


--dl*
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alanleeknots

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Re: Load testing of various Bowline structures
« Reply #55 on: June 10, 2015, 06:13:00 AM »
Hi All,
       Mark I have one more here, I don't know what to call yet, have the same nipping structure with "Lee s loop"
       no sure you have any interest on this one.  It look very nice .   

       謝謝 alan lee
« Last Edit: June 10, 2015, 06:49:51 AM by eric22 »

alanleeknots

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Re: Load testing of various Bowline structures
« Reply #56 on: June 10, 2015, 06:14:01 AM »
Lee s loop
« Last Edit: June 12, 2015, 02:31:53 PM by eric22 »

Mobius

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Re: Load testing of various Bowline structures
« Reply #57 on: June 10, 2015, 10:10:33 AM »
Hello mobius,

When are you planning to commence testing your Bowline structures?

I need to know because I would like to use your data (with permission) in the 'Analysis of Bowlines and other selected Eye knots' paper.

Please advise....

Thanks, Mark G

Hi Mark,

I am very busy with work commitments for two and half weeks, then I have holidays. I was planning to do trials then, especially now that "knot wars" has become a more serious undertaking and I need a more careful approach and methodology than perhaps I originally intended :)

You are welcome to use my results when I have them, they just won't be there to use that quickly I am sorry.

I need to go through this thread and look carefully at what is to be trialled and make a list. As it turns out, the two creations I would like to trial do have something to offer us anyway I think:

Mobius "Eskimo" Bowline: has a 2D turNip, however one diameter tends to hide quite a lot behind the other under load. It would not surprise me if this knot is one of the weakest trialled, however that will be interesting to find out.

B&B Bowline: technically it has a 3D turNip, yet that turNip is a large one where other component parts of the nub crowd in. Effectively, it seems bigger than 3D to me. This Bowline certainly isn't traditional in lots of ways, however trialling this knot vs other 3D bowlines might prove interesting.

Cheers,

mobius

xarax

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Re: Load testing of various Bowline structures
« Reply #58 on: June 10, 2015, 11:44:18 AM »
   Hmmm, I've found that kernmantle ropes --exactly because the kern (often) comprises individual cords not cohesive themselves, hence needing the mantle, are (more) compressible given that these individual cords can spread out within the mantle.

   All things are relative ! Kernmantle ropes are, in general, less compressible than braided ropes. Why ? Because those more or less parallel fibres/cords inside the core, are packed inside the mantle, and they are bounded by it. If the mantle encircles them tightly enough ( so there are no voids left in between them ), the rope can not be compressed easily, because a circular cross-section can not be deformed into a flattened, elliptical one of an equal area - provided that its perimeter / circumference does not change, and that the fibres/cords can not be compressed, the cross section of the mantle can not but remain more or less circular.
   Now, if the fibres/cords are able to swim freely inside the mantle  :), then yes, a kernmantle rope can be squeezed as easily as a braided one, and even more ! That was my idea of a rope made from fibres/cords arranged around an easily compressible central core ( made of some elastic material ) : this rope could be flattened very easily, and this would enable it to deform almost freely, fill the voids inside a nub, and thus maximize contact area and friction. I believe it is a common knowledge that knots tied on multi-lines, are tighter/safer than knots tied on a single line, and this was the origin of this idea of easily flattened ropes.     
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xarax

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Re: Load testing of various Bowline structures
« Reply #59 on: June 10, 2015, 11:51:50 AM »
I can see someone making just the opposite charge : that stiff ropes defeat allowing a knot to achieve its truest manifestation (as might come from some mathematical modelling algorithm, say ) !

  True. I suppose that all ropes can follow a curve of even a one-rope-diameter radius - if tensioned hard enough. However, with very stiff ropes, you are right : material restricts geometry.
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