Author Topic: Second order retucked/enhanced harness midline loops and the equivalentEOL loops  (Read 23876 times)

Kost_Greg

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Quote
l wonder if they've been tied before.

Centuries ago, no doubt.

That might be the case, but until proven otherwise, a moniker like Double Alpineer's FBK loops, sounds eligible and rather euphonic so far ( aka Double Lineman's ABK loops :)).
« Last Edit: May 19, 2020, 03:53:04 PM by tsik_lestat »
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agent_smith

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Requesting load testing to determine jamming resistance in the following loading profiles:

[ ] Bi-axial loading from SPart-to-SPart
[ ] Eye loading (with one SPart anchored)

Alan Lee perhaps?

Or anyone else?

Kost_Greg

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                                                                         Mirror tying method

1. Form a Z loop, a bight, and an S loop knotting scheme, like the one illustrated in first image (in contsast with the tying method described at reply#1, where the initial configuration was S loop, bight, Z loop).

2. Place the S loop over the Z loop, (or the Z over the S loop), as shown in second image. Note, that you have to place the S loop, (or the Z loop), on Z loop's segment that is a direct continuation of the bight component, in contrast with the tying method presented at reply#1.

3. Pass the bight through this configuration, in the following order, ~ under, over, under, over ~.

The resulting mirror knot is shown in the next two images, in a loose dressing state, in front and back view.
« Last Edit: July 09, 2020, 04:09:03 PM by tsik_lestat »
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agent_smith

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Can I assume that the TIB and bi-axially through loadable (BTL) eye knots presented at reply #31 and #32 are a claim of originality by tsik_lestat?

I need confirmation from the creator - because I really like these knots and want to include them in my upcoming paper on the #1053 Butterfly knot.

I also need to know if any load testing has been done to investigate jamming threshold in a variety of different loading profiles such as:
[ ] bi-axial through loading (from SPart-to-SPart so that the eye is isolated from load)
[ ] axial eye loading (in both directions aligned with each respective SPart)
[ ] transverse loading of the eye (some may prefer to use the term 'ring loading')

Has Alan Lee done any load testing?
« Last Edit: May 23, 2021, 05:46:51 AM by agent_smith »

Kost_Greg

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New evidence has emerged, which suprisingly prove that the EHL midline eyeknot, is a pre-existing knot structure, and apparently, a very old one too.

I have recently been informed by a brilliant collaborator and a valuable contributor, Knotsaver (Saverio), who has a thorough knowledge about knotting, that there had been a short reference of the knot presented in this thread, in the book "Encyclopedia of knots and fancy ropework" by Raul Graumont and John Hensel, first published in 1939, which appears in chapter II, titled "Simple knotting" on page 58, under the moniker of Cask knot.

I have attached photos of all the related content, thanks to Saverio, who was kind enough to enlighten me and deliver all the related material from his own book copy.

In this short reference, the authors provide an "in the end method" of tying the inline profile (??), and they also claim that there is no practical value, without providing any supporting arguments.

Having delved deeper into the mechanics and the topology of this particular knot structure, i'll have to add that i respectfully disagree with the viewpoint of the authors.

Also, many thanks to master Xarax, who has managed to ferret out another, a bit more recent, appearence of the knot, on a knotting board from the Mariner's museum and Park in Houston Texas, which dates from 1954.

It is number 64, the photo at the end of the page is great, you can zoom in to see all the details of this magnificent artwork.

Link : https://catalogs.marinersmuseum.org/object/CL2899

Anyone, who may know or may sniff out any additional info about the so called "Cask knot", is encouraged to appose it in this topic for further evaluation!

Afterall, we are still on the lookout for the original creator! :)
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siriuso

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tsik_lestat

In the same Plate 21, page 57. the configuration of the Jug Sling (Fig.1-A B) is the same as Cask Knot (Fig.8-A B). Also see my previous reply #12 and 18.

Happy Knotting
yChan

Kost_Greg

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Siriuso, thank you for your apt observation, you may consider it as my omission, even though i was aware for their illustration in the same plate, of the book cited previously.

Although the topological equivalence between the two knots (cask/jug sling) is obvious, but not pointed out by the authors (their omission :D), it seems to me that a couple of component rearrangements, render two geometrically and functionally separate configurations.

Note also the resemblance, between your depicted tying method, (taken from the book), and the one described in detail, at reply#32.

Yet still, we didn't get any closer to the mysterious Cask knot inventor, did we? :)
« Last Edit: February 14, 2021, 07:20:53 PM by tsik_lestat »
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agent_smith

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This reminds me that any claims of originality - in the fullness of time - can be hard to sustain and may result in disappointment.
Oh well.

What occurs all too often is independent rediscovery.
I'm surprised Dan Lehman hasn't chimed in with comments about the Hensel and Graumont publication... where the accuracy and reliability of the published content is often called into question.

I agree with tsik_lestat that the authors comments re "has no practical value" - is itself of no value!
I think some testing needs to be undertaken to determine jam resistance in various loading profiles.
The #1053 Butterfly knot jams when heavily eye loaded (when the eye is loaded axially in alignment with an SPart).
However, #1053 Butterfly is jam resistant when bi-axially through loaded (from SPart-to-SPart).

I have loaded this knot only to 2.0-3.0kN and found:
[ ] eye loaded (with the eye loaded in axial alignment with an SPart) = a lot of distortion but did not jam at these loads
[ ]  bi-axially through loaded from Spart-to-SPart = a lot of compression of the core but did not induce jamming.
(using human rated EN1891 or EN892 rope)

Obviously, these loads are trivial and more work needs to be done.

Kost_Greg

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           A detailed analysis of the Cask, second order, bowline

Starting from a Z nipping loop this time, as the most favoured nipping form, i have tied a conventional 1010 bowline, and have straightened the bight structure, or in other words, i have formed a marlinspike, or a snap bowline.

Considering that, if i load the first image structure, i bring back the 1010 bowline, how do i get to retain this three stage (two from the SPart and one from the out-going leg), marlin spike nippin form?

One way is to capture SP and then follow the returning structure routing, with a marlinspike bowline, but this is not what i'm looking for in this case.

In the second (cask) method, the direct SPart continuation, is designated as the primary nipping loop (of the nipping structure), which clamps both collar legs (bowline rule), as shown in second image.

The last maneuver, is to feed the WE back through the collar, parallel to SP (third , fourth image).

This is the heart of the knot, where the tug end is being subjected to a forceful, three (or four) strand, constriction effect, which firmly secures it.

I count eight contact/constriction points in total , with this interweaving, three in the snap stage, and five in the Cask stage, which leads me to believe that this is a super inherently secure, jam proof, bowline.

PS1 : The knots are illustrated from a detailed angle/view of a bowline (except last image).

PS2 : The 7th constriction point (the collar),as the less nipping component, is not actually part of the nipping structure, however, if i was to enhance it with more nipping action, i would had tied the knot in reverse, which is also a very secure , decent, profile.
« Last Edit: May 16, 2022, 11:15:18 AM by Kost_Greg »
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Kost_Greg

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                                              The Dines and the reverse Cask knot

The idea is to reverse the previous structure, by forming at first the Cask scheme, as a nipping component, then interweave it with a crossing knot.

The first phase of this process is to create the Dines knot. If someone examines the Dines from both sides, he/she will notice the four nipping stages (two from the SPart and two from the outgoing eye leg) of the tug end, as shown in the first two images.

Considering that, Xarax and Alan Lee showed that when this adjustable mechanism is loaded, it locks/capsizes in two fixed forms, the Chinese loop and the Samisen bowline, the same question stands in this case too:
How do i get to maintain this remarkable, symmetrical nipping form, with the less possible distortion?

The answer is to complete the second part of the reverse Cask knot by capturing the returning eye leg and then follow Sp's routing.

While this final maneuver stabilises the Dines nipping form, making the most of all its solid nipping power,  it also subjects the tug end to a second constriction wave by the nipping structure (6  salient constriction points in total), this time with more nipping action by the collar (third ,fourth image).

I find no need this time to cross the ends for more nipping power, because there is more than enough, in order to qualify as a super inherently secure configuration (without the use of overhands or eights) :D!

Yes, it will cinch a lot more in relation to the  previous structure, but hopefully, not to a point of initiating jamming.
« Last Edit: May 15, 2022, 06:05:05 PM by Kost_Greg »
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Dan_Lehman

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Also, many thanks to master Xarax, who has managed to ferret out another, a bit more recent, appearance of the knot, on a knotting board from the Mariner's museum and Park in Houston Texas, which dates from 1954.
Whoa !!  The MM&P is in Newport-News, Virginia.
There is a "Houston Maritime Museum", I see.

Quote
Afterall, we are still on the lookout for the original creator! :)

By which you mean, I presume, somebody who is believed
to have first tied the knot.  One can see multiple origins at
times --maybe with a sense of their chronology, or not--,
and see paths from (or not!) them to general awareness.
E.g., we have from the late Bob Thrun a published article
to a small caving newsletter in which he presents what was
later, in a Pop. Sailing(?) article entitled "Zeppelin Knot"
--a name authors of the article came up with.  To my point,
I think it's reasonable to believe that the origin of awareness
of the knot likely comes from the latter source, albeit that one
possibly of later discovery than Thrun's.  Also, for the lineman's
loop, there was an early publication and then a later one in
a climbing journal, which latter likely influenced at least climbers
and not the first (though I still want to dig into lineman literature
to see any appearances there).


--dl*
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mcjtom

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An interesting 'enhancement' to #1050.
But I'm not entirely sure if this offers anything beyond the performance capability of #1053 Butterfly...

Is the jury still out?

Kost_Greg

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By which you mean, I presume, somebody who is believed
to have first tied the knot

Had anyone been fiddling with the jug sling structure, a knot that dates fom the ancient times, which comes between the end of the line and inline Cask, it is more likely that he might had come across to it.

Sometimes it is in front of our eyes but the mind is not prepared for it yet.

By the way, i really hold in high regard TIB knots (there are very few indeed, see Cask, Butterfly, Harness), with the property of transitioning directly from end of line to inline.

I don't have the whole picture yet, i speculate that this has to do with their so called "pseudo" symmetry.
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Dan_Lehman

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Quote
By which you mean, I presume, somebody who is believed
to have first tied the knot

Had anyone been fiddling with the jug sling structure,
a knot that dates fom the ancient times,
which comes between the end of the line and inline Cask,
it is more likely that he might had come across to it.

Sometimes it is in front of our eyes but the mind is not prepared for it yet.
Indeed!!
Lonnnnnnnnng ago I played with variations on a Fig.8
base, where the Returning Eye Leg ran straight back
through the knot, to then put in --what seemed natural
to borrow from the BWL-- a collar around the SPart,
tucking back through the knot.  Well, at that point
of collaring ..., Just Say NO! :: i.e., stop and be done,
having there tied (what I call) the "Quick8" !!  --which
knot can be given a nice further securing by arcing
the tail back to make one more tuck, out between
the eye legs at their entry/departure point.

Recently, it is (what I'm calling) the "Tail-Loaded BWL"
(TLB / TLBwl), which is #1010 loaded on its tail --which
loading, NB, is not so simple as stated; i.e., the tail must
be brought back on the one not other side of the knot,
so as to get more of a nipping LOOP vs. arc (which e.g.
the Crabber's Eye Knot has)!
Of course, the BWL has been before us for ages; only
this year (or 2021) have I seen that SOMEone has found
another way to use that tangle; I'm hoping to be able
to learn who & how.  (Conceivably, some person thought
that they were tying #1010 and ... emerged with the TLBwl
instead, and found it satisfactory IN SOFT WEBBING.)

--dl*
====

mcjtom

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An interesting 'enhancement' to #1050.
But I'm not entirely sure if this offers anything beyond the performance capability of #1053 Butterfly...

Is the jury still out?

Would the 'Cask' loop for example be less jamming than the Butterfly when loop-loaded or be more resistant to slipping at the extreme axial loads?  Tying it in the Bottle-slig fashion is quite fast and easy.