Author Topic: The Sheetbend loop knot and the Carrick bend loop knot.  (Read 8271 times)

DerekSmith

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The Sheetbend loop knot and the Carrick bend loop knot.
« on: August 09, 2018, 08:57:04 AM »
Yesterday I was reading a report by Grant Prattley wherein he referred to a 'Sheetbend Loop - the WE was tied back onto the SP using a Sheetbend - hence a Sheetbend loop.  I think most of us here would perhaps call it the Antibowline.

Then, this morning in a perverse moment, I was browsing through Wikipedia and I came across this :-

"Carrick bend loop or Carrick loop is a knot used to make a reliable and stable loop at the end of a rope formed by the tail turned around and attached to the main part using a carrick bend."

To make matters worse, there wasn't a carrick component in sight, just the Josephine mat with a loop on its side.

https://upload.wikimedia.org/wikipedia/commons/thumb/c/c4/YomaBagiHalkasi.JPG/440px-YomaBagiHalkasi.JPG

Of course, they are quite right - all loops are bends back to the SP - so simple.

Derek
With even less hair now than I woke up with...

agent_smith

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #1 on: August 09, 2018, 11:59:34 PM »
per Derek:
Quote
Of course, they are quite right - all loops are bends back to the SP - so simple.

Actually - not quite right!

For instance, #1053 derived Butterfly bend has [a] corresponding eye knot that breaks this rule.
And that is #1053 Butterfly eye knot.

I have posted images elsewhere on this forum showing a range of corresponding eye knots derived from a Butterfly bend.

agent_smith

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #2 on: August 10, 2018, 12:30:29 AM »
per Derek:
Quote
Yesterday I was reading a report by Grant Prattley wherein he referred to a 'Sheetbend Loop - the WE was tied back onto the SP using a Sheetbend - hence a Sheetbend loop.  I think most of us here would perhaps call it the Anti-bowline.

The article is here: http://overtheedgerescue.com/technical-rope/sheet-bend-vs-bowline-knot

On that blog, he shows 2 images at the top of the page. Both are 'eye knots'.

The image at top right is an eye knot - it is not a 'bend'.
In fact, it is an 'anti-Bowline' - or, it is also sometimes known as an 'Eskimo Bowline'. It probably has this reference to 'Eskimos' from the slipped version of the Anti-Bowline (sometimes known as a 'Kalmyk' eye knot).

Grant Prattley has gone into radio silence...I have been in direct contact with him about multiple inaccuracies with his knot test reports - carefully and respectfully pointing out the issues.

I had explained that his report on the differences between the #1010 Bowline and the 'Anti-Bowline' should be amended but he appears to be steadfast and resolute in using the term 'Sheet bend' to describe what is in fact an eye knot (ie anti-Bowline).

I am not sure that he fully understands the difference between a 'bend' and an 'eye knot'.

He also recently published a report about slide and grip hitches that he employed as 'progress capture devices' (PCD) in micro-hauler devices.
The AZTEK is one very popular micro-hauler. Link: https://www.rockexotica.com/aztek/
I own and regularly use an AZTEK myself.

Grant runs a few tests and as is fairly typical of the entire rescue/climbing community mindset - all conclusions are based on pure MBS yield (ie its a contest of strength, and the winner of the strength contest is declared superior).

Here is the link to the slide and grip hitch test report: http://overtheedgerescue.com/rope-rescue/jigger-progress-capture-testing/

I have given Grant extensive feedback on this particular report.
My main criticism is that once you reach around 4.0kN load, slide and grip hitches start to seize and jam on the their parent rope. In other words, their ability to function as a 'PCD' is impaired because they dont release easily. It is critically important that a PCD is able to release and then grip again, with that cycle repeating as hauling is undertaken.

I took extensive high quality photos of various slide and grip hitches (6.0mm hitch on 8.0mm parent cord - all Sterling USA material) - and at the threshold of 4.0kN - initial seizing/jamming commenced. This would severely impair the function of a micro-hauler that employed slide and grip hitches as a PCD.

Grant Prattley based his report on pure MBS yield - which is non-sensical...because once you reach 4.0kN load, the slide and grip hitches begin to seize/jam. Which is counter-productive and impair the micro-haulers function.

Furthermore, it is unlikely that a micro-hauler will be subjected to very high loads - and Grant didn't specify a situation where a micro-hauler would be subjected to loads above 10kN.

And my last point was that in his tests, at no time did he apply load to the parent (8.0mm) cord. He only applied load to the slide and grip hitches - and not the parent cord. This was an oversight in my view. Loading the parent cord could have an effect on the ability of the slide and grip hitch to function effectively.
Testing should have investigated this possibility.

In any micro-hauler device, all of the 'parts' (or falls) of cord reeved through the pulleys will experience tension force simultaneously. And testing of slide and grip hitches should have tried to replicate that situation by also loading the parent cord.

I had intended to post my peer review report on this forum but, there is no coherent place to post. This forum needs an entirely new topic category that is dedicated to knot test reports and peer review of those reports.
« Last Edit: August 10, 2018, 04:05:09 AM by agent_smith »

Dan_Lehman

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #3 on: August 10, 2018, 01:42:54 AM »
Of course, they are quite right - all loops are bends back to the SP - so simple.
I've given up on advocating for Ashley's sense of
"bend", using "end-2-end knot" in its place.

There are various correspondences between eye knots
and e-2-e knots, which I've noted previously.  One of
the relationships I pointed out was that of making an
end-2-endS knot --i.e., tying bight-ends to a single
end in the desired knot, and then see how to *fuse*
one of the bight ends to the single end,
and there you have an eye knot in a single piece
of material (subsuming the prior eye formed of
the bight tied to the single line).

The bowline has long been regarded as related
to the sheet bend but without remark that I'm aware
of that the latter is asymmetric and so offers two sides
that could bear the eye; look for how it would be were
the other side doing it.  Then one can try the single-end=
to-bight-ends method of determining corresponding eye
knots.

Now, in many cases, such determined eye knots will
be bulkier than one might want.  And some might be
known already but without seeing the relationship to
the particular end-2-ender.


--dl*
====

DerekSmith

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #4 on: August 10, 2018, 05:45:26 PM »
My OP was intended to be 'tongue in cheek', but as you both have responded quite professionally, I suppose I must 'put my wig back on' and respond accordingly.

One of the nice things I find about being surprised by a naive or 'different' approach to something, is that it offers us the opportunity to expand or refocus our perspective which might have become quite 'constrained'.

Yesterday I discovered two staringly obvious aspects of knots 

1. That some knots have no type (bend, hitch, eye ) they are just knots - obvious, trivial even, but arguably as important to knot science as zero is to mathematics.

and

2.  That all loop knots are bends configured such as to form a loop from two of the available ends.  Simple, trivial even, but fundamental in the understanding that all loopknots are loops bound by a bend.  It does not matter if the loop legs are configured opposite, adjacent or tangential, they will still be loops bound by a bend.  Of course, the functionality of the knot depends totally upon  how those four ends are connected up - do I have a Beckett, a Bowline or an Antibowline - each with its particular characteristic response to force and usage, but they are all sheetbend loopknots.

So, although Grant Prattley would have been better served had he called his second loop by one of its common names, I must none the less applaud him for his insight in calling it what it is -  a Sheetbend loopknot.

Likewise, the suggestion that the Alpine Butterfly loopknot is not a bend is also self evidently wrong.  Cut the loop and you have a bend formed from two interlocking OH knots - it is a bend that is configured as a loopknot.

A loop has two ends, these ends are bound, this binding is a bend.

And as a parting comment, I have argued extensively on the subject and do not subscribe to the blanket term 'Eyeknot' being applied to all loopknots.  In the lexicon I adopt, the loopknot is the parent term, a small subset of loopknots may be further defined as eyeknots  if they are small loops with looplegs adjacent and particularly if they are intended to take an eye thimble.

Derek
« Last Edit: August 10, 2018, 05:57:12 PM by DerekSmith »

DerekSmith

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #5 on: August 10, 2018, 05:55:26 PM »
@Mark

re http://overtheedgerescue.com/rope-rescue/jigger-progress-capture-testing/

Likewise, I have occasionally had the Prusik jam solid on even modest loads, consequently, I now use the Valdotain Tresse (VT)  with a keeper pulley because it transfers its load in a much more progressive fashion into a far greater length of holding rope.

Has your testing run to including the VT?

Derek

agent_smith

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #6 on: August 11, 2018, 12:59:20 AM »
per Derek:
Quote
So, although Grant Prattley would have been better served had he called his second loop by one of its common names, I must none the less applaud him for his insight in calling it what it is -  a Sheetbend loopknot.

But he didn't use that terminology.
He identifies it simply as a 'Sheet bend'.

And by a strict definition, this is incorrect.

A bend unites 2 ends, to form a join.

I think Grant was trying to point out that the core structure of an 'Anti-Bowline' is closely linked to the core structure of a 'Sheet bend'.

But, an Anti-Bowline (aka 'Eskimo Bowline') isn't a 'bend' - its an 'eye knot'.

per Derek:
Quote
Likewise, the suggestion that the Alpine Butterfly loopknot is not a bend is also self evidently wrong.  Cut the loop and you have a bend formed from two interlocking OH knots - it is a bend that is configured as a loopknot.

#1053 Butterfly is (as I conceptualise it) an 'eye knot'. It isn't a 'bend'.
Yes, when you cut through the 'eye', you transform it into an end-to-end joining knot (ie a 'bend').
The physical act of 'cutting' - is key to understanding. You cut, which then destroys the 'eye'. At which point, this act of destroying the eye transforms the structure into something different; an end-to-end join.
There is a correspondence between 'eye knots' and 'end-to-end joining knots'.

An eye knot enables connections to the 'eye' (eg a carabiner for instance - or direct to a climbers harness).

An end-to-end joining knot, does not allow connections - because there is nothing to connect to.

I have attached an image of an 'eye bolt'.
It isn't a loop bolt or a bight bolt. It is an eye bolt.
An eye bolt permits connections.
In the same way, an 'eye knot' permit connections.
Indeed, one could ask the proverbial question, what is the intended purpose of an 'eye knot' (what Ashley refers to as a 'loop knot')?
In the case of #1047 F8, its purpose is to form a connection to something (eg a carabiner).
The same could be said of #1010 Bowline - it is to connect (or attach) to something.

If I had 2 water pipes, I could join them together (with a coupler). That now unites the 2 pipes in an 'end-to-end' configuration. There is no 'eye' in this join - because there is nothing I can connect to. Its simply a join.

This brings me to the difference between a 'loop' versus an 'eye'.
Or, the difference between a 'bight' and a 'loop'.

For instance, all Bowlines (by definition) have a 'nipping loop' as a key element of their structure.
It not a nipping eye or nipping bight...its a loop (ie a closed helix).
So for me, a loop takes the form of a closed helix.

An 'eye' isn't in the form of a closed helix.
And neither is a 'bight'.

I have always been keen to straighten out and refine/clarify knot terminology - and we have tried to do this in this IGKT forum several times in the past. Each time we try to get consensus, we seem to bog down and spin our wheels - and we end up nowhere.

Clifford Ashley used the term 'loop knots' to describe a class of knots that enable connections to what he called a 'loop.
You have to go back to the 1940's (ie that era) to understand his reasoning.
I believe his book is a remarkable achievement for its time - and it still is held in very high regard. But, some 70 or so years later, we have made progress.
Ashley made errors (obviously) - and one has to forgive this particularly when you consider that he had no computer and the internet like we do today (which makes his effort all the more remarkable).
As an example, please look at illustrations #1057 and #1058 in ABoK. He describes these 2 structures as 'Bowlines'.
In my view, Ashley did not have a clear set of rules to define [a] 'Bowline'.
The same can be said of his understanding of what a 'loop' is in relation to a 'bight'. The same can be said for 'turn' versus 'loop'.

Xarax advanced his theory that a 'bight' structure within [a] 'Bowline' is actually consisting of:
[ ] a 'collar' and
[ ] 2 'legs' (ie, an entry leg and, an exit leg)

This helped to nail down the definition of [a] 'Bowline'.
Ashley didn't conceptualise 'Bowlines' in the way we do now.

And lets face it, we (on this IGKT forum) still argue about terminology!

Derek, I would like to direct your mind to the structural difference between a #1431 Sheet bend and #1010 Bowline.
There are some who argue that there is a functional  'nipping loop' in #1431 Sheet bend.
In my view, this proposition is incorrect.
And this comes down to how you choose to conceptualise what a 'nipping loop' is..and indeed, what is a 'loop'.

Xarax had advanced that a loop is a closed helix.
I had further advanced that a 'nipping loop' is loaded a both ends.

EDIT NOTE: I have received word from Xarax in relation to further refining the definition of a 'loop' (ie closed helix).
Xarax points out that a 360 degree arc is not an absolute defining requirement. He suggests that a 'loop' may still be regarded as such even if the helical arc is less than 360 degrees. However, he further points out that we must be careful in making the distinction between a 'bight' and a 'loop'. That is, at what point does a bight transition into a loop? In a classical sense, the legs of a 'bight' are parallel. When the legs cross - and the helical arc increases, we transition into a 'loop'. So Xarax is questioning at what point is the extent of the helical arc sufficient to be regarded as a 'loop'.
« Last Edit: August 11, 2018, 10:19:42 AM by agent_smith »

DerekSmith

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #7 on: August 11, 2018, 01:33:53 PM »
@ Mark
Quote
But, an Anti-Bowline (aka 'Eskimo Bowline') isn't a 'bend' - its an 'eye knot'.

Yes, of course, a Loopknot, or an Eyeknot are not bends.  If you take a deep breath, make a cup of tea and give yourself a moment to consider the point I am making, the wheels might stop spinning and develop a little traction.

My observation is so 'obvious' it is almost trivial, I almost feel ashamed for not noticing it before, it is that all fixed Loopknots (and their subset, Eyeknots) are made from bends.  All fixed loops have two ends and these ends are tied (bent) together using a bend.

If you take a long length of rope and tie the ends together with two entwined OHs in the form of an Alpine bend or a Sheetbend, then you have a loop formed using bends.  It matters not how large that loop is, nor how you intend to use it, the whole entity is a Loopknot and has been constructed using a bend.

I am not asking anyone to call loopknots bends, trivially, I am observing that all fixed Loopknots are made with bends.and I thanked Grant's ignorance of the Eskimo to bring this obvious fact to the forefront of my attention.  A case of the obvious hiding in plain sight.

[Actually, by not knowing of the Eskimo, grant missed the fact that the Eskimo is reported as having a significantly improved resistance to ring loading, and would therefore have been the better of the two Loopknots for the application he pictured.]

Quote
I have always been keen to straighten out and refine/clarify knot terminology - and we have tried to do this in this IGKT forum several times in the past. Each time we try to get consensus, we seem to bog down and spin our wheels - and we end up nowhere.

Indeed, and it can be frustrating to distraction.  But so long as we continue to discuss  issues and respect others opinions, even when we cannot share them, then there is a chance at least for the forum to continue to be a place for development.  This is particularly true when the issue is not based on fact, but only on preferred nomenclature.

An Eyebolt (AKA a Ringbolt) is not a knot, so can we please remove it from the attempt to justify calling a Loopknot an Eyeknot, this is just silly and does nothing for the credibility of the argument you and Xarax put forward.

Yes, you are right, this has been discussed at length already when you were preparing your paper on the Bowline.  I did not agree with the arguments you put forward then, and I note nothing new has been added to the argument.  You may remember it was one of the reasons I asked for my name as one of the contributors to be removed from the report.

My lexicon is :

A fixed loop formed in cordage is a Loopknot : It does not matter what use the loop is put to, nor is it dependent on the presence of additional load line(s), although most Loopknots are configured to utilise an external load line.
A specific subset of Loopknots are called Eyeknots ;  this subset is characterised by small loops with the load legs being parallel going into the knot, and are likely to be used to incorporate an eye thimble.

I do not subscribe to the objective to rename all Loopknots as Eyeknots.

The Bowline and the Eskimo are Loopknots.
Some configurations of the Alpine Butterfly may be termed Eyeknots (although this distinction has little significance).

Derek

agent_smith

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #8 on: August 11, 2018, 03:24:23 PM »
Hi Derek,

I'm simply engaging with you in a professional discussion - not necessary for any deep breaths, cups of tea or long pauses. It is these types of discussions which help to advance our collective knowledge. Its all good...nothing wrong here. We are simply exercising our creative minds...

per Derek:
Quote
all fixed Loopknots (and their subset, Eyeknots) are made from bends.  All fixed loops have two ends and these ends are tied (bent) together using a bend.

and;

Quote
I am not asking anyone to call loopknots bends, trivially, I am observing that all fixed Loopknots are made with bends.

I respectfully think you need to refine your definitions. The term 'loop knots', and 'eye knots', 'bent' and 'bends' have too much inter-dependency in the way you construct your explanation - and it is difficult to extract a coherent theory as a result.

In my view, your use of the term 'loop' needs to be carefully qualified.
What I think you are trying to describe is a 'round sling'. When you take a singular length of cord/rope, and create a join by uniting its 2 ends, you end up with a round sling (or, aka a circle). This does not alter the fact that an 'end-to-end joining knot' was used to form the sling (circle).

But, if we take 2 separate pieces of cord/rope, and unite the 2 pieces - so that we increase the overall linear length, it is not a round sling (or a circle).

So, I think you need to be clear on that distinction...in that - is the end-to-end joining knot made with a singular piece of cord/rope or; is the end-to-end joining knot uniting 2 separate pieces of cord/rope?
As a thought experiment, consider the example of uniting 2 separate pieces of cord. Lets say that I wanted to form a round sling (ie circle). I would in fact need to make two joins (using 2 'end-to-end joining knots').

Also, I respectfully disagree that 'eye knots' are a subset of 'loop knots'. For example:
[ ] #1010 Bowline = eye knot
[ ] #1047 F8 = eye knot
[ ] #1053 Butterfly = eye knot

The term 'loop knot' is a throw back to the era of Clifford Ashley.
The 'loop' to which he refers - is an 'eye'.

I think a stricter definition of what constitutes a 'loop' is required.
And it is here that I think a theory ought to be advanced on precisely what is a 'loop'.
I think your definition of what a 'loop' is - differs from my conceptualization.
It might be instructive to try to differentiate between the following terms:
[ ] loop
[ ] bight (at what point does a 'bight' transition into a 'loop'?)
[ ] turn (how is a 'turn' distinguished from a 'loop'?)
[ ] nipping loop (what distinguishes a 'loop' from a 'nippng loop'?)


Quote
An Eyebolt (AKA a Ringbolt) is not a knot, so can we please remove it from the attempt to justify calling a Loopknot an Eyeknot, this is just silly and does nothing for the credibility of the argument you and Xarax put forward.

An 'eye bolt' is different from a 'ring bolt'! Please refer to attached photos.

And the analogy is (in my view) important. And I am not being disrespectful - rather, I am advancing a different understanding.
An 'eye bolt' is intended for connections/attachments.

When I tie #1047 F8, I intend to form connections (eg to a carabiner, or to a climbing harness, or to a sturdy tree).

Quote
this subset is characterised by small loops with the load legs being parallel going into the knot, and are likely to be used to incorporate an eye thimble.

I think you will run into difficulties with this definition - and I respectfully disagree.
There is no 'subset' per se.
As I have pointed out - I think the heart of the matter lies with your definition of a 'loop'.
It is possible that when you use the term 'loop' - perhaps you are referring to a round sling?

If i may use the specific example of #1047 Figure 8... in my view, this is an 'eye knot'. The 'eye' is what Ashley likely refers to as a 'loop'. When I tie #1047 F8, it could be connected to the following possible examples:
[ ] a small tree
[ ] a very large tree
[ ] an even larger tree
[ ] a small boulder
[ ] a very large boulder
[ ] a carabiner
[ ] a climbing harness

It does not matter what size object i attach the knot to... the 'eye' can be made as big, or as small as desired, to form the connection.

No thimble is required.
Indeed, the use (or non use) of a thimble has nothing to do with the definition of an 'eye knot.
« Last Edit: August 11, 2018, 05:05:24 PM by agent_smith »

DerekSmith

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #9 on: August 11, 2018, 06:33:43 PM »
Mark,

Thank you for remaining professional in your reply, it is appreciated, although from your good self, nothing less would be expected.

Sadly, although you made a lengthy reply, the wheels are still spinning, your argument has not gained traction because nothing new has been added to or substantiated in your reasoning.

If you would allow me to paraphrase the situation as I see it.

You have decided that all the knots described by Clifford Ashley as Loopknots will be renamed as Eyeknots for three reasons :-
A.  ABOK is a "throw back to the era of Clifford Ashley"
B.  Loopknots have the same form as a metal Eyebolt .
C.  The commonplace existence of spliced eyes (with or without thimbles).
Have I missed anything significant?

On the basis of these arguments, I reject you claim to rename all Loopknots as Eyeknots as follows:

A.  ABOK remains the defacto reference for knots.  Very little within it has been shown to be in error, and time alone does not change the nature of a knot.

B.  A metal eyebolt is not a knot.  Many other objects have a fixing / retaining hole in them, they are not knots.

C.  A splice is not a knot, it is a reformulated / restructured cord.  However, it is made from cordage and I acknowledge that small loops of the form created in eye splices are a subset of the family of Loopknots and may be recognised by the term Eyeknots provided they conform to the type of 'Small, with parallel loop legs and typically expected to be used with an eye thimble'.

Having made the case to reject the renaming you propose, I would like to continue with the constructive suggestion you then made - I agree, the clarification would be valuable.

Quote
I think a stricter definition of what constitutes a 'loop' is required.
And it is here that I think a theory ought to be advanced on precisely what is a 'loop'.
I think your definition of what a 'loop' is - differs from my conceptualization.
It might be instructive to try to differentiate between the following terms:
[ ] loop
[ ] bight (at what point does a 'bight' transition into a 'loop'?)
[ ] turn (how is a 'turn' distinguished from a 'loop'?)
[ ] nipping loop (what distinguishes a 'loop' from a 'nippng loop'?)

The distinction is straightforward.

The [ ] Loop -  or more correctly in the context of this discussion the Fixed Loop - is closed - the two loop legs are bound in the Loopknot.  Both legs must be bound otherwise we have a Noose which is not what we are discussing.

The other three are components and are all distinguished from the loop by not having their ends bound.

Apart from decoratives, a Fixed Loop is generally regarded as being available for a purpose - generally for attachment.  Of note, knots generally contain many bound loops, turns, bights etc.  but as these are not generally available for any purpose other than to perform the function of closure and stabilisation of the knot itself, they are not used to describe the functional group of the knot.

Finally, when I mentioned that an Eyebolt was AKA a Ringbolt, I checked first that I was right in making this statement.

see the Scaffolders m16 Ringbolt image.

Derek

agent_smith

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #10 on: August 12, 2018, 12:23:31 AM »
Indeed, this is an intellectual discussion - and that is one of the purposes of this forum - to facilitate discussion.
We dont all have to agree of course - and thats fine. But, I sense that you might reach your limits of acceptance of this back n forth discussion at some point?

I don't profess to have all the answers Derek - but I do like to have a solid theory / set of rules to describe knots.

I do feel that the key to this discussion is nailing down (ie solving) knotting definitions/terminology (eg 'loop', versus 'bight', versus 'turn', versus 'hitch', versus 'end-to-end join', etc).

per Derek:
Quote
You have decided that all the knots described by Clifford Ashley as Loopknots will be renamed as Eyeknots for three reasons :-
A.  ABOK is a "throw back to the era of Clifford Ashley"
B.  Loopknots have the same form as a metal Eyebolt .
C.  The commonplace existence of spliced eyes (with or without thimbles).
Have I missed anything significant?

You asked the question; "Have I missed anything significant".
My respectful response is; Yes. You have missed a lot of significance (and that is not intended as an insult - its simply my response to your question).

In reference to your point 'A':
ABoK was published in the 1940's.
Ashley wrote his masterpiece in that era (obviously) - and he was bound by the limitations of understanding at that time.
Ashley didn't have the internet or a computer (obviously). So he couldn't collaborate like we can today.
It is unlikely that Ashley engaged in technical discussions like we are now - with peers from around the world. I would say that he tried to source written texts that were available to him at the time - but the content was largely evolved from his mind and his personal experiences - together with the common vernacular at the time. So, Ashley's use of the descriptor 'loop' was the best effort for that era. Things were less complex in those days - there wasn't the multitude of new knots and Bowline discoveries as we have today - so classifying things was somewhat easier. Precise use of language to clearly define what a 'loop' is wasn't necessary. It was sufficient to simply use the term loop - and it wasn't questioned.

With the virtual explosion of new knots claiming the title of 'Bowline' - I (and others) found ourselves in a position of having to more clearly and precisely define what constitutes [a] 'Bowline'. And this gave rise to the concept of a 'nipping loop' (which I conceptualise as a closed helix that is loaded at both ends). And this definition had to be distinguished from an 'eye' (which is fixed, and not collapsing like a noose); and so on...

Now, I did say that the term 'loop knot' was a throw back to the era of Ashley and ABoK. But, I didn't say; "ABoK is a throw back to the era of Clifford Ashley" - since that wouldn't make sense!
What I was referring to is that Ashley's use of the term 'loop' - is what I conceptualise as an 'eye' (and yes, by definition, the 'eye' is fixed - otherwise it wouldn't be an eye, it would be a noose).

In reference to your point B:
I did not state that; "Loop knots have the same form as a metal eye bolt"
Respectfully, I am not sure how you derived that understanding? (you will not find those typed words - because I would never make such a remark).
Please understand that my reference to eye bolts (which are distinct from ring bolts), is to provide an analogy.
The idea being that an eye bolt provides a means to connect or attach something.
Its the same with 'eye knots' - in that the 'eye' permits connections/attachments.
Obviously, a metal eye bolt isn't a knot. It was simply an analogy.
In terms of terminology, if I walked into a hardware store - I would ask for an 'eye bolt'. I wouldn't ask for a 'loop bolt' or a 'bight bolt'. Its 'eye bolt'.
In the same light, there is 'eye splice' - it isn't 'loop splice' or 'bight splice'.

With reference to your point C:
"The commonplace existence of spliced eyes (with or without thimbles)"
I looked back over my previous posts and could not find any specific argument that I tendered in detail about eye splices.
However, I would again emphasize that an 'eye splice' permits connections/attachments to the 'eye'. It is an analogy.
I would not refer to an 'eye splice' as a 'loop splice' or a 'bight splice'.

Derek, with respect - I dont think you have tendered a precise definition of what constitutes a 'loop' so as to clearly distinguish it from a 'bight' and a 'nipping loop' and a 'turn'.
For example, at what point do you consider a 'bight' to make the transition to a 'loop'? And how do you distinguish between a 'turn' and a 'loop' (and indeed a 'hitch')?
For example, Xarax has advanced that a 'loop' takes the form of a closed helix, but does not require a full 360 helical arc to be scribed. He says it can be less than 360 degrees.
Also of interest is distinguishing a 'bight' from a 'loop' (in precise, measurable language).
(I also feel that you haven't addressed my distinction of a round sling that is formed by taking 2 ends of a length of cord and then uniting the ends with an 'end-to-end joining knot' - which you possibly refer to as a 'loop'?).

Some random points:

It is implied that the 'eye' in an 'eye knot' is fixed. It does not act like a noose. I sometimes conceptualise a noose as having a collapsing eye.

I did point out that Ashley made a number of errors in ABoK - but this is understandable. Firstly, he is (was) human -and all humans make mistakes, we are not infallible. Secondly, Ashley didn't have the power of a computer and the internet like we do today. He did have multiple entries for the same knots, and in my view, he did not have a robust theory of what constitutes [a] 'Bowline'. I gave examples of 2 entries in ABoK that were erroneously labelled as 'Bowlines'.

Ashley's definition of [a] 'bend' is problematic. And further, he wasn't clear on the correspondence between eye knots and bends. In my view, a clearer term is 'end-to-end joining knot'.

I think you haven't fully defined what a 'turn' is. For instance, does a 'turn' form around an object? Example is a 'round turn and 2 half hitches'. Does a 'turn' uniformly encircle a parent object? Is 'uniform encirclement around an object' a necessary qualifier? If yes, then how many degrees of arc must be scribed to create a 'turn'? The encirclement usually takes advantage of the 'capstan effect'.
Xarax had proposed qualifying terms such as:
[ ] 'U turn' to denote a 180 degree partial encirclement
[ ] 360 degree uniform encirclement (with each end exiting at opposite sides)
[ ] 540 degree uniform encirclement (where the tail exits in the same direction and in parallel with its own SPart)...and this would be a 'round-turn' in the common vernacular. A capstan effect would play a role.

And the term 'hitch' - eg #1763 Prusik hitch.
Does a 'hitch' form around a parent object and exert a force upon that object? For example, a 'Prusik hitch' exerts a force by crushing the parent object that it is formed around. If you remove the parent object, the hitch ceases to exist. Note that uniform encirclement isn't a qualifier to be classed as a 'hitch' (in my view).

And #1195 'Munter hitch' - is this a subset of hitch termed 'load control'?
For a Munter hitch to function, it needs to form around a parent object (eg a carabiner). If you remove the carabiner, the Munter hitch ceases to exist. It is possible to control loads using a Munter hitch...and indeed, in my view it works because of a 'capstan effect'.

With reference to eye bolts:
Link: https://en.wikipedia.org/wiki/Eye_bolt#Ring_bolts
Note the sub reference to 'ring bolt'.

Ring bolt references:
[ ] https://www.bunnings.com.au/zenith-110-x-9-3mm-galvanised-ring-bolt_p3968405
[ ] http://wireropeshop.co.uk/wire-store/index.php?main_page=index&cPath=17_87
[ ] https://www.sheridanmarine.com/product/ring-bolt


EDIT NOTE:
I have made numerous grammatical corrections and clarifications to make sure that my use of language is as precise as I can achieve (with my non scholarly education level). This is so what I wrote is more difficult to misunderstand.
« Last Edit: August 12, 2018, 03:19:00 AM by agent_smith »

knotsaver

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #11 on: August 12, 2018, 07:18:43 AM »
Hi Mark and Derek,
(English is not my mother tongue but I want to say something)
about the terms "eye" and "loop":
the fact that the term "eye" was/is used in the term eyesplice could mean that the eye is a fixed loop knot but un-untie-able (non-untiable)(or that it will never be untied). It is like a ringbolt.
The term "loop" for fixed loop is used (and can be used) for untie-able (or that can be untied) fixed loop/eye. It is like a shackle (hitched at the end of a rope).
--
about the terms "loop", "turn", "bight"
I follow Cirus Day:
"loop" is a closed or nearly closed curve in a rope or line (but it is often used to mean a fixed loop, or loop knot);
"turn" is a loop round an object;
"bight" is the curve in the loop, but it also means the middle of a rope or line.

The nipping loop could be so named nipping turn (in fact often the term turnip is used (after Dan Lehman?)) when it encircles for instance the collar legs of a Bowline.

...my 2 cents.
Ciao,
s.
« Last Edit: August 12, 2018, 03:51:27 PM by knotsaver »

agent_smith

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #12 on: August 12, 2018, 12:30:41 PM »
Thanks 'knotsaver'.

I think I am slowly going loopy.

To challenge Clifford Ashley's conceptualization of a 'loop knot' - is for sure going to put me on a lot of peoples radar screens.

Nevertheless, in my view, a qualifying concept is that an 'eye' permits connections/attachments.
For example, #1047 F8 is a knot that permits connections/attachments.

The ability to untie an 'eye' or permanence of that 'eye' is not a qualifying requirement in my view. But, I take your point that an eye in an eye splice implies 'permanence'. Although one could unravel the splice if desired - since it isn't absolutely permanent. But, an eye  splice is - for all intents and purposes - intended to be permanent.
As I have already advanced, an 'eye' simply refers to a component of the knot where connections/attachment can be made.

I note that the 'eye' in knots such as #1047 F8 and #1010 Bowline does not have crossed legs. That is, the 'legs' of the eye are not crossed.

In contrast, a 'loop' takes the form of a closed helix - there is an overlap of 2 rope segments which creates the helical form.

A 'turn' is formed around an object (but not a rope segment within the same knot structure). An 'object' can be things like a post, a rail, a tree, a bollard, a pipe, etc. A qualifier is that the rope uniformly encircles the object (but it can be just a 180 degree 'U turn').
« Last Edit: August 12, 2018, 12:33:41 PM by agent_smith »

DerekSmith

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #13 on: August 12, 2018, 03:17:12 PM »
@Mark
Quote
We dont all have to agree of course - and thats fine. But, I sense that you might reach your limits of acceptance of this back n forth discussion at some point?

In this you are quite correct.  It was behind my opening comment "Sadly, although you made a lengthy reply, the wheels are still spinning, your argument has not gained traction because nothing new has been added to or substantiated in your reasoning".    And yes, in the absence of any substantive rational argument for the change, there will be no reason for continuing discussion.

The majority of people use and understand the term Loopknot to mean a knot which creates a fixed loop (i.e. not a Noose).  You wish us to drop this and call all Loopknots by the term Eyeknots.  Of course, there is nothing stopping you from deciding for yourself to use the term and put up with the consequential confusion you cause when in discussion with other knotters.  But, if you wish to induce the rest of us to adopt this substantial change, then the onus falls upon your good self to provide all the evidence and justification for why it is either wrong to call them Loopknots, or the harder one to substantiate - why it is better to call them Eyeknots.

As I have stated before, the detailed reasoning you have given in substantiation of reasons A. B. and C. are not for me, significantly substantial to justify or warrant a change of this magnitude.

I fully accept and applaud your attempts to rationalise the aspects which make a Bowline a Bowline.

The Bowline has two components within the knot and three components outside of the knot; these are :  within the knot a Simple Hitch (SH) Component and a Bight Component, and externally it has a Loop Component, an SP Component and a Tail (or WE) Component.  The two principle 'flavours' of this arrangement - the Bowline and the Antibowline alternate the placement of the SP with a loop leg.

You have identified the SH Component as a 'Nipping Loop' and defined this as the definitive 'essence' of a Bowline.  It then seems to me (please correct me if this impression is wrong) that having used the term 'Loop' in the  'Nipping Loop' you then sought to eliminated its use in reference to the loop external component.  This, if true, is unacceptable. You might have instead found an alternative term for your 'Nipping Loop', such as a Turn Component or a Simple Hitch Component.

I feel that most of this created confusion stems from the fixated thinking of our friend Xarax, and although I rarely agreed with him, I will say no more on the subject as he chooses not to be here to argue his points.

Derek

DerekSmith

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Re: The Sheetbend loop knot and the Carrick bend loop knot.
« Reply #14 on: August 12, 2018, 03:24:55 PM »
@Mark

Quote
I think I am slowly going loopy.
  -  it is good to see you are retaining your sense of humour.

Quote
Nevertheless, in my view, a qualifying concept is that an 'eye' permits connections/attachments.

I wonder, has it escaped your attention that an external Loop Component of a Loopknot  also permits connections/attachment?  Which of course it would do because it is the same knot, only the name of the loop is being changed.

Derek