Author Topic: Carrick Bend, revisited  (Read 20543 times)

[Inkanyezi] gone

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Re: Carrick Bend, revisited
« Reply #15 on: November 15, 2010, 08:46:41 AM »
Oh, I didn't intend to pick nits.

I take it that when that sentence was written, other origins might have been unknown. The knot topology is the same as other knots that as we know may have been used in other places and described before. The tying method is overly complicated; the "hybrid" being so much simpler that it is a Columbi egg solution.

The discourse in this thread has changed my view on the tying method slightly; an almost automatical movement that I forgot to mention, but which may be important to point out. It escaped me at first, just as one of the most important features when drawing up the slipknot bowline. Here there is also a similarity in the two methods. For the slipknot bowline, it is important to keep the end away while drawing up the knot. For the Carrick Bend, in order to avoid slip of the ends, the pattern, once formed, must be flipped over, so that the ends hang freely down from the knot. When done like that, there is no slip when it is drawn tight.
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[Inkanyezi] gone

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Re: Carrick Bend, revisited
« Reply #16 on: November 15, 2010, 10:51:16 AM »
xarax, I know your opinion. There is no need to repeat it over and over, and all those references are to your own scribblings on the matter. We do not share the same opinion on how to work that knot, and I don't need any persuasive efforts from your part. I know perfectly well how to make a Zeppelin bend, and i also know that it is an amply secure knot that does not jam, and I know how to open it. I was reflecting over the different properties in tying patterns, and you have not changed anything by repeating yourself, but you are trying to hide the fact that all four parts must be engaged behind a veil of verbosity.

So, your opinion is clear. Mine too.
« Last Edit: November 16, 2010, 12:37:09 PM by Inkanyezi »
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Dan_Lehman

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Re: Carrick Bend, revisited
« Reply #17 on: November 15, 2010, 06:19:31 PM »
Oh, I didn't intend to pick nits.

I take it that when that sentence was written, other origins might have been unknown.

This might be debatable re the "Strait" --though there, one could think "of course,
that is essential of any such mid-line eye knot".  Re "Benson", egads, THIS
one is Ashley's #1421 --that should be at least suspected and then confirmed (by
(m)any party(s))!  And re Anglers Loop, no, not a nit : look in most any angling
shop and you will find the very knot tied in that modern material Toss claims made
it obsolete.  (And re this knot, I might've discovered a version that works as well
and maybe stronger --some simple testing to be done, yes-- and that can serve
in rope.)  Beyond these, one should also take issue with the assertion under
an earlier section on "Lashmanship / Pulley, Frap, and Wdge", where a theoretical
3:1 construct is given "close to" that advantage even considering friction
--whereas the practical user should expect less than 2:1.  (The issue re such
constructs has been debated in this forum, with my contributing some data
from simple testing with even 'biners (more efficient than cordage!) & weights.
It was quite eye-opening to see the loss of advantage.)

Quote
The discourse in this thread has changed my view on the tying method slightly

It occurs to me that one can begin by forming a turn around a bight,
then bringing the bight's tail around appropriately to insert through itself.

Quote
For the Carrick Bend, in order to avoid slip of the ends, the pattern, once formed, must be flipped over,
 so that the ends hang freely down from the knot. When done like that, there is no slip when it is drawn tight.

I think it's more problematic than this --I'm not fearing gravity's draw
on ends, but imbalanced folding especially in firm slick rope where
movement can occur more for one than the other rope.

BTW, much is sometimes made of Ashley's calling this bend nearly perfect,
and many sources claim it to be very strong.  In fact, some test data (old)
shows it to have unexceptional strength, and I don't know of any modern
testing (i.e., using modern cordage).  It has been said to serve well the
Alaskan crabbing industry (by one contact, and apparent use shown on
t.v. on one boat).  I know of no test of the seized lattice form.
.:.  We are wallowing in --too often the case re knots--
a great void of information from the lab & from the field.
In such emptiness, there is room to go off in all directions
unobstructed and only encountering sounds, mostly echoes!


 - - - - - - - - - - - -

XaraX, you need to look more carefully at the knot, not the keyboard.
Quote
1. Whatever of the two ends/tails the standing part pulls, it has exactly the same result in the knot s strength, I think.

There is a noticeable difference of geometry if one orients the knot's tails
in a certain way.  In the simple and commonly presented geometry, they
align adjacent on the axis of tension, SParts making a 1-diameter turn around
them; but in the version I intend, the Sparts turn more broadly, and that is
what leads me to conjecture "greater strength".  Getting this orientation takes
some careful placing of the ends and then careful setting --dressing AND setting
are mindful acts.

But all of this plays on fine details of form, material, and load (and where is
strength --or i.p. what actual difference might be in the balance here-- much
of any importance except when doing breaking-strength tests?  (But where is
XaraX much at all concerned about knots --in his latter-day feeling-- than in
such tests of knotting theory ?!!   ;D  )

 - - - - - - -

In the disposition of the knots' tails, I see a trio of orientations for the
Carrick bend and at least as many for Rosendahl's bend .
In the former, Inkanyezi shows one in the OP, tails making a sort of
2-diameter object perpendicular to the axis of tension; then there is
the case where the tail is brought in the direction SPart draw is pulling
it, where it is pressed into the knot's collar; and then one can push
the tails around in the opposite direction (and these two latter versions
give more of a 1diameter SPart u-turn).  For Rosendahl's Z. bend
one can get that first Carrick form, too, each SPart pulling a tail
into such orientation; one can also form the knot as I argue above and
as is commonly shown, where tails go in opposite directions from the
first-described form.  There can be variance per loading, but with careful
dressing I think that these forms can be dependably given.


--dl*
====
« Last Edit: November 22, 2010, 08:27:45 PM by Dan_Lehman »

[Inkanyezi] gone

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Re: Carrick Bend, revisited
« Reply #18 on: November 16, 2010, 12:47:27 PM »
Oh, I didn't intend to pick nits.

I take it that when that sentence was written, other origins might have been unknown.

This might be debatable re the "Strait" --though there, one could think "of course,
that is essential of any such mid-line eye knot".  Re "Benson", egads, THIS
one is Ashley's #1421 /.../

And my reflexion re nitpicking is that I do not regard the book as an encyclopedic work, but rather an instructive book. There may surely be exaggerations and omissions of earlier sources, but the quote and image that I point out is an error, and in my opinion a severe error. Benson's and the Butterfly might have been shown in earlier work, I didn't care to look for their references in the ABoK even, just because my intention is not to pick nits, but to point out a more important mistake. it is intevitable that any book might contain erroneous statements, I didn't look for all of those, I pointed out one that does us a disservice.
« Last Edit: November 16, 2010, 12:49:45 PM by Inkanyezi »
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Dan_Lehman

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Re: Carrick Bend, revisited
« Reply #19 on: November 17, 2010, 09:11:30 AM »
And my reflexion re nitpicking is that I do not regard the book as an encyclopedic work, but rather an instructive book. There may surely be exaggerations and omissions of earlier sources, but the quote and image that I point out is an error, and in my opinion a severe error. ...

Fair enough, I suppose, as far as that goes.  But then there is
so much reference to Ashley i.p. in this presentation that it is
most surprising for what one might expect to be recognized as
a common, long-known knot to be found!

The two other citations I made I think are "severe" enough :
that Anglers loop is worthless in (then-) modern, monofilament
fishline (when it is actually ubiquitous), and that one can get
"close to" the theoretical mechanical advantage with rope sheaves!
--that thinking can lead to some serious practical impasses.

(I found the Anglers Loop in rope, once, in some area of commercial
fisher discards (plastic drums of netting, also); it had apparently served
as a mid-line eyeknot, loaded on both ends (for some sort of task).)

--dl*
====

[Inkanyezi] gone

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Re: Carrick Bend, revisited
« Reply #20 on: November 17, 2010, 12:36:55 PM »
Of course it boils down to the Carrick Bend being a pet peeve of mine; I really didn't care to use those other knots, so I didn't pay much attention.

The Angler's Loop or those other bends may be useful knots, but they're not in my toolbox, which is probably the reason why I didn't go into detail there.

The reason I chose the Carrick Bend as my preferred bend is mainly that it is sufficiently secure and easily tied under harsh conditions. It simply joins many desirable features, not all of them present in many knots. I did not know by then of a reliable method to tie the Butterfly Bend in a simpler way.

Regarding "strong", I don't subject the lines to anything near breaking strength, except if I want to test how much it takes to break one. So in my eyes, any knot, with no exception, weakens the rope about half from the manufacturer's declared strength. I usually regard the maximum working load as the manufacturer's strength divided by seven. With that arithmetic, there's little difference in strength between different knots. I don't know of any knot that effectively would cut the rope, so I don't bother a lot about strength in knots.

However I do regard ease of tying as well as ease of untying as important features, together with reliability. That's where in my toolbox, the Carrick Bend wins hands down over most knots. My most used knots do not rely on vision for tying, but are all formed by a well planned choreography, a set of movements with the hands, which lead to the desired pattern. I have not been able to adapt that to any intertwined overhands except the EDK/ORB and the Butterfly. The Carrick Bend is the easiest to untie of those, followed by the Butterfly, which is easier to tie.
« Last Edit: November 17, 2010, 11:06:15 PM by Inkanyezi »
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