Author Topic: Locked cowboy bowline similar to Scott's locked bowline  (Read 2361 times)

jarnos

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Locked cowboy bowline similar to Scott's locked bowline
« on: July 02, 2021, 09:09:09 PM »
If you use cowboy bowline (ABoK #1034 1/2) as base and lock it by threading the working end through the eye, through the nipping loop and finally through the collar along the standing part, you get an eye-knot reminding of Scott's locked bowline, but additionally being tiable in a bight (TIB). Is there a name for that knot? Who invented the knot?

« Last Edit: July 09, 2021, 03:05:00 PM by jarnos »
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Dan_Lehman

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #1 on: July 02, 2021, 10:26:40 PM »
Re Who invented the knot?
--by which I surmise you expect a single-person as the answer
(as opposed to remarking that you seem to have done so (too)--,
I can only note that Scott put forwards the original,
and Mark has noted what you have presented in his
"Bowlines Analysis" --to wit (caption beneath image):
Quote
Scott's Locked Bowline can be made TIB if the tail is set outside of the eye
and then the locking maneuver begins from the inside of the eye.
--which version gains what is likely a far more important
quality than mid-line tying (not relevant to tie-ins, afterall!) :
a 2dia. turn for the tail to make --more easily done for firm rope!

--dl*
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jarnos

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #2 on: July 02, 2021, 11:50:09 PM »
Oh, it was presented by Xarax whoever he/she is at https://igkt.net/sm/index.php?topic=19.msg20616#msg20616. That is in the same thread where SS369 presented the now called Scott's locked bowline earlier.
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jarnos

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #3 on: July 03, 2021, 06:32:00 AM »
So the knot was not invented by Scott and it has different properties. Thus I think it should not be called just Scott's locked bowline even if someone does
at https://igkt.net/sm/index.php?topic=6907.msg45453#msg45453.
« Last Edit: July 03, 2021, 06:41:17 AM by jarnos »
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jarnos

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #4 on: July 08, 2021, 02:08:40 PM »
Mark Gommers calls ABoK #1034 1/2 as Tail outside Bowline in his Bowline Analysis (Version 3.0), which describes it pretty well. Maybe it could be as basis when naming the locked bowline.
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agent_smith

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #5 on: July 10, 2021, 04:40:58 AM »
As I had pointed out - there are 4 versions of Scotts locked Bowline.
[ ] 2 are based on #1010
[ ] 2 are based on #1034 1/2

Of these 4 versions, only one is 'TIB' (Tiable In the Bight).

I personally use the TIB version for various life critical applications (using human rated EN892, and EN1891 ropes).
The other 3 versions are also suitable for life critical applications (in human rated 'EN' ropes).

...

I had also pointed out that the easiest way to determine if a knot is 'TIB' is to reverse engineer it.
That is, try to untie it without access to either end.
If the knot can be fully untied (without access to either end) so that no remnant knot remains - it is proven to be 'TIB'.

...

Ashley refers to #1010 as a 'right hand' Bowline.
He refers to #1034 1/2 as 'left hand Bowline'.

In my view, this is an unfortunate decision.
Tail inside and tail outside the eye are more appropriate descriptors.

I am of the view that Ashley didn't have a fully developed concept of 'chirality' - or indeed a solid theoretical basis for defining a 'Bowline'.
The essential and fundamental component of all 'Bowlines' is the nipping loop - which can in fact be formed with right-handed ('Z') or left-handed ('S') chirality.
The nipping loop is 'TIB' and must be freely able to trap and crush rope segments contained within its encircling diameter.
The absence of a functional nipping loop is grounds for automatic disqualification from being classified as [a] 'Bowline'.

...

Ashley also states that #1034 1/2 (tail outside) Bowline is inferior to the #1010 tail inside version.
This strongly suggests that Ashley did not have a fully developed understanding of the effects of a transverse load on the eye (some may prefer to use the term ring loading).
When the eye of a #1010 Bowline is subject to a transverse loading profile - it is becomes unstable and can progressively slip and fail.
The #1034 1/2 tail outside Bowline is resistant to a transverse loading profile.

jarnos

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #6 on: July 10, 2021, 06:59:34 AM »
As I had pointed out - there are 4 versions of Scotts locked Bowline.
[ ] 2 are based on #1010
[ ] 2 are based on #1034 1/2

Of these 4 versions, only one is 'TIB' (Tiable In the Bight).

No, two of them are TIB. They are just mirror images of each other. It is trivial. But if there are two knots based on different knot, why do you call them the same?
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agent_smith

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #7 on: July 10, 2021, 10:49:11 AM »
per jarnos:
Quote
No, two of them are TIB.
More accurately - there are is only one - within a chiral orientation.
Therefore, to be tedious and painfully correct, I should have added; "within a chiral orientation".

It is tedious to always refer to the mirror versions - and it can also be misconstrued.
Virtually all knot book authors only illustrate a knot within one chiral orientation.
You'll never (or very rarely) see the mirror versions also illustrated in their books - their books would double in size/volume.

If you really wish to be tedious - you can argue that their are 8 possible versions of Scotts locked Bowline.
But this starts to get confusing - and could be misleading.

Its tedious to always have to spell out and make it clear that whenever a knot is illustrated, their also exists its mirror version.

Its sort of like having to always point out that their is also an anti version of all the sub-atomic particles. We tend to only refer to a neutron, proton and electron. Yes - there is also an anti proton, anti neutron and anti electron (positron). But - it just starts to get tedious.



« Last Edit: July 10, 2021, 10:50:42 AM by agent_smith »

jarnos

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #8 on: July 10, 2021, 12:41:50 PM »
agent_smith, do you mean there is a knot that you call Scott's locked Bowline that is based on #1034 1/2 and that is not TIB? Can you show that one? You tell it is tedious to refer to mirror versions, but I think it is the same as to refer to versions that have opposite chirality.
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agent_smith

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #9 on: July 12, 2021, 03:20:53 AM »
Happy to engage with you while it remains courteous and does not devolve into a knowledge contest... :)

The 4 fundamental Scotts locked Bowlines (within a chiral orientation) - are all based on the simple #1010 Bowline (tail inside) or simple #1034 1/2 Bowline (tail outside).
The locking tail maneuver is carried out per Scotts original concept.
See image below...

I don't say that there are 8 fundamental Scott locked Bowlines - because it can be misconstrued.
If you wish to declare all 8 - the following qualifying remark is necessary; "taking onto account both S and Z chirality" (but this gets tedious).

I note that virtually all knot book authors only illustrate one chiral orientation of their presented knots.
The size/volume of their books would almost double - if they illustrated both chiral forms for each knot.

Ashley generally only illustrates the 'Z' chirality orientations of his 'Bowlines' in 'ABoK'.
He does not illustrate the 'S' chirality versions.

Having said that - I would remark that there are times where it is important or necessary to point out both chiral orientations - and/or mirror versions of knots.

NOTE 1:
I don't include the Xarax variant as one of the fundamental Scotts locked Bowlines.
The tail maneuver in this version performs a U turn (180 degrees) around the outgoing eye leg.
Reference link: https://igkt.net/sm/index.php?topic=4517.msg30269#msg30269
At the time of his post (Nov 08, 2013) - Xarax did not report that this variant is also TIB.

NOTE 2:
In some of the earlier posts dating back to 2011-2013... the notional reference to 'left hand' and 'right hand' was in conflict with the concept of chirality (ie 'S' and 'Z' loops).
Ashley also confuses this issue where he describes right-hand and left-hand Bowlines.
In my personal view, the Simple Bowline can be either tail inside (#1010) or tail outside (#1034 1/2) the eye.
The term 'right-hand' should be reserved for 'Z' chirality and the term 'left-hand' should be reserved for 'S' chirality.

Dan_Lehman

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #10 on: July 12, 2021, 11:48:10 PM »
As I had pointed out - there are 4 versions of Scotts locked Bowline.
...
The absence of a functional nipping loop
is grounds for automatic disqualification from being classified as [a] 'Bowline'.

And what qualifies a knot to be a "Scott's Lock BWL"?
Given your four, I will find three more, at least
--one of which I see Alan found, in your ref'd old thread--
(and NSUE ones, to boot, which seems to tickle
some folks' fancy, though it's irrelevant for a tie-in).

(But I'd better tear away before I go googly-eyed
trying to discern one from another, and nevermind
chirality (mirrors are cheaply, readily available) !
As Marvin lamented, "Oh, no, not another one.")

Doesn't Scott look lovely with all his Locks?!


--dl*
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agent_smith

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #11 on: July 13, 2021, 02:28:34 PM »
per Dan Lehman:
Quote
And what qualifies a knot to be a "Scott's Lock BWL"?
Given your four, I will find three more, at least
Perhaps you should direct your question to Scott :)

I am not Scotts spokesperson - but, I do admire his discovery.

Although Scotts original presentation was directly based on #1010 Simple Bowline - the locking manoeuvre can just as easily be applied to #1034 1/2.
I am 100% confident that Scoot was aware that he could apply his locking manoeuvre equally to #1034 1/2.
The fact he didn't post images as such - matters not to me - it is obvious that it can apply to both #1010 and #1034 1/2.

In my view, the 3 additional versions I showcase are obvious and in keeping with Scotts original #1010 based presentation. Any tail locking manoeuvre that goes a step beyond Scoots original concept is a different species.

This is contestable - it is not definitive - its my personal view.
You may hold a different view - and you may accept other tail locking manoeuvres that are more complex...which would extend the range of possible 'Scotts locked Bowlines'.

I prefer to set limits - and narrow it to a group of 4; otherwise you open the floodgates and broaden the definition.

Dan_Lehman

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #12 on: July 13, 2021, 07:40:28 PM »
per Dan Lehman:
Quote
And what qualifies a knot to be a "Scott's Lock BWL"?
Given your four, I will find three more, at least
Any tail locking manoeuvre that goes a step beyond Scoots original concept is a different species.

The "step beyond" details are the question.
All that you've accepted have the tail tucking
initially back BETWEEN returning eye-leg bight's
legs (whew!); what Alan saw & I now see are
that one might tuck back on the away-from-outgoing
eye-leg (& crossing point) side, too; some of these
are NSUExtre'mite's.  They seem close enough to
the Scott seed for inclusion --same *movement*
but a slightly different path.


--dl*
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agent_smith

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #13 on: July 13, 2021, 11:34:20 PM »
per Dan Lehman:
Quote
The "step beyond" details are the question.
Its not in question in my mind.
The phrase; "A step beyond" - refers to a tail maneuver that differs in character and basic geometry compared to Scotts original concept.

In examining Scotts original presentation - with the tail locking maneuver applied to the Simple Bowline (#1010):
1. The tail performs a U turn around the nipping loop and re-enters that nipping loop between the legs of the collar.
2. The tail then exits through the collar - and follows the SPart on a parallel pathway.
3. The tail is firmly clamped between the legs of the collar, due to the action of the nipping loop.

Seems simple enough to me :)
Are you seeing something of a different character?

The 3 additional fundamental Simple Bowlines that I advance are of the same general character as Scotts original presentation.
Which brings the tally to 4.

As stated - Scott did not originally post photos of the locking maneuver applied to #1034 1/2 (tail outside Simple Bowline).
But - it is obvious - and I am confident that Scott knew it was obvious - and so he didn't think it imperative to also photograph his locking maneuver on the #1034 1/2 structure.

I note that you (ie Dan) rarely post any photos of your creations or indeed photos depicting technical detail. Maybe you see the act of photographing knot creations as tedious and/or too time consuming?
Maybe Scott was also time poor - and only managed to photograph the #1010 Simple Bowline? As stated, I am sure that Scott was aware of the existence of #1034 1/2 tail outside simple Bowline, and that his tail locking maneuver could also be applied to that structure.

NOTE:
I do not say that there are 8 fundamental Scotts locked Bowlines, because this could be misleading.
There are 4 (within a chiral orientation).
If one wished to assert there are 8 - this would have to be qualified by declaring both chiral geometries - being 'S' and 'Z'.
I find it tedious and unnecessary to do so.

EDIT NOTE: Refer to my earlier post for photos of the 4 fundamental Scotts locked Bowlines...
« Last Edit: July 13, 2021, 11:36:29 PM by agent_smith »

jarnos

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Re: Locked cowboy bowline similar to Scott's locked bowline
« Reply #14 on: July 14, 2021, 12:22:58 AM »
Scott presented his bowline with a photo and by saying:
Quote
I want to offer an easy method of securing the WE of a "standard" bowline
« Last Edit: July 14, 2021, 01:03:30 AM by jarnos »
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