Author Topic: A mechanism of developing two wrap TIB hitches directly from simple eyeknots  (Read 503 times)

Kost_Greg

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More or less, i believe this is a rather known procedure to most knotters, but not so well showcased.

It concerns the development of a TIB formation, being fed with both lines for the hitch to be created.

Example: Feeding the cow hitch with both ends , one may get the TIB running cow.

Starting from a simple, S-based cowboy bowline, I have illustrated its marlin spike form in first image.

All one has to do is to feed the other end through the nub, following the initial line side by side, for the flat form, and then closing the two wraps in a way that creates the third image pole form.

Moreover, by pushing the initial line out of the nub, (right line, second image), one can get the infamous gnat hitch, (nice way to make it TIB), which afterall, is a kinda marlin spike hitch.

This technique applies to all kinds of bowlines, (anti-bowline, normal, cowboy), for similar results, and i 'm not sure if it has been recorded before.

However, the hitch has to be studied more thoroughly, if it has to be tied aytonomously, with the end method, or perhaps develop another in the bight method.
« Last Edit: September 27, 2023, 10:48:10 AM by Kost_Greg »
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agent_smith

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Quote
one can get the infamous gnat hitch, (nice way to make it TIB), which afterall, is a kinda marlin spike hitch

I personally wouldn't go quite so far to comment that a 'Gnat hitch' is "kinda Marlinspike hitch".

By definition, a Marlinspike hitch (#1789) requires an external toggle - refer image below.
When the [external] toggle is removed, the Marlinspike hitch loses structural integrity and collapses.

As with all things knot related, it is important to agree on definitions - and indeed - many disagreements arise from the interpretation/understanding of definitions.
In the case of a Marlinspike hitch, I am applying a strict definition that an external toggle is required.

In fact, Canyoneers (in canyoning activities) use a double Marlinspike hitch with a plastic external toggle to create a retrievable abseil system.
(refer to image for exact geometry of the double Marlinspike hitch).
Canyoners refer to the external toggle as a 'Fiddlestick'.

A Gnat hitch is a type of noose hitch - it is formed around its own S.Part.
I routinely use a Gnat hitch as an adjustable foot stirrup in fixed rope ascending.
It is an adjustable noose - and it holds well when load is applied.
I find the Gnat hitch to be effective when employed as an adjustable foot stirrup using EN564 accessory cord (works well with Sterling USA EN564 cordage).
In my view, there is no external toggle mechanism in a Gnat hitch.

However, I accept that an internal toggle mechanism can be employed in some hitches using a tail segment of the rope/cord.
This would - in a sense - function as a pseudo rope toggle.
But, language is important in definitions - and it is necessary to make a distinction between an internal (pseudo) rope toggle versus an external toggle (eg a 'Fiddlestick').

...

As a side note, I have not found a way to tie a Gnat hitch using a 'TIB' method.
That is, I need access to an end to tie a Gnat hitch.
NOTE: It is possible to tie a Gnat hitch with a bight - but this is 'cheating'!
(with a bight means the same way that #1074 Bowline with-a-bight is formed).

..

Although not trying to hijack or derail your post - the geometry of a double Marlinspike hitch is very interesting - when the Fiddlestick is removed, no remnant line twists must be left in the rope.
A perfectly symmetrically tied Marlinspike hitch will not work - because it leaves one full remnant line twist.
It takes some degree of practice to get the geometry correct - and there are 2 basic geometries - each a mirror of the other - and is dependant on which direction the abseil rope is fed around or through an anchorage.
« Last Edit: September 27, 2023, 03:21:41 AM by agent_smith »

Kost_Greg

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Thank you for your apt intervention agent_smith, you are quite right, i should have made the distinction between the forms, like Ashley is doing when he describes the clove hitch, which requires a host object in order to be formed, and the buntline, which is a clove structure being fed with a "pseudo" rope toggle as you call it.

Adding also Xarax's bull clove that requires two "pseudo" rope toggles being pushed through the clove form, i would claim that all three are quite different configurations.

So, i suppose you wouldn't had any objection, if i was to replace, the rope(s) of first and second image with an external toggle, and call it, marlin spike hitch, would you?

Hence, to conform with the standard definitions, having original post's second image as a reference structure, i would comment as follows:

1. Replace the toggle ropes with an external toggle for a marlin spike hitch.

2. Keeping only the right line as the load line, you get the mooring hitch (non-slipped).

3. Keeping only the left line as the load line, you get the gnat hitch.

4. Keeping both lines inside the nub, you get the TIB hitch of OP's third image.

Therefore, an alternative title for the original post would be " The gnat hitch meets the mooring hitch in a two wrap TIB configuration". :) :)

To avoid any confusion, i have to point out that i'm illustrating the mirror structures, from those that are usually analyzed in various books and posts.

I would like to ask you as a regular gnat user, or perhaps the original creator, or anyone else who has tested it like so, if there is any difference, if the load line was to be inserted from the other side of the nub (refer to attached image).

That would shape a slightly different topology, with the gnat tail placed near the SP. (not near the eye as the original gnat structure).

Never i had thought about the double marlin spike hitch, it seems very interesting and practical.

                                                            EDIT NOTE :

As a side note, I have not found a way to tie a Gnat hitch using a 'TIB' method.
That is, I need access to an end to tie a Gnat hitch.
NOTE: It is possible to tie a Gnat hitch with a bight - but this is 'cheating'!
(with a bight means the same way that #1074 Bowline with-a-bight is formed).

Yes, that's true, in this gnat case, a TIB nipping structure (crossing knot), does not maintain the TIB property, when being interweaved with one main line, in marlin spike fashion, it requires two of them. (internal toggles).

However, if a one wrap TIB hitch is all we need, we can always keep just one line and the other closed (refer to second attached image).

This one wrap, TIB hitch development, derived from the two wrap configuration, is actually an additional property, which does not apply to all bull-like hitches.

The bull hitch, for example, loses its structural integrity, and collapses, if one of the wraps is getting closed.

Nonetheless, there are TIB stucture formations, that do maintain the TIB property employing one or even two internal rope lines.

Also, closed form schemes (overhands, eights), might meet the tibness with one internal rope engagement (figure eight noose).
« Last Edit: October 01, 2023, 01:52:11 PM by Kost_Greg »
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