Author Topic: Analysis of Bowlines paper uploaded for review and comment (PACI website)  (Read 196746 times)

DerekSmith

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #315 on: January 16, 2016, 06:32:51 PM »
I don't want my knot to change
classifications per force or material!

I emphatically agree with Dan's point here.

I likewise agree with both Dan and Andy.

But as I learnt as a child - 'I want - don't get'

I want my #1010 to remain a #1010 under all usage loadings and in all possible materials, but this just isn't going to happen.  Extreme ring loading with jerking or cordage with very low CFs and my #1010 will either become something else or will cease to exist.

This brings me to a problem I have with Dan's warning over mixing THEORY with REALITY..

First, we are not dealing with a Theory here, we are attempting to define working descriptions for the purpose of classification.  And as we are dealing with the classification of working knots, those descriptions must be sufficiently robust as to be able to accommodate the reality of a working knot.

A Bowline (for which the default knot is #1010) is a fixed loop knot.
The SP feeds into the knot under a stabilising collar directly into a nipping loop (turNip component) which provides the anchor force for the knot by clamping the exiting WE.
The outgoing leg of the nipping loop forms the outgoing leg of the fixed loop, which returns via the nipping loop to the collar and from the collar, exiting back through the nipping loop to the WE.
The nipping loop is stabilised by the two bight legs of the collar and the collar is partially loaded from one leg of the main loop.
The Bowline is not stable under heavy ring loading when it will morph into a variety of forms eventually ending in a noose.
The Bowline does not exhibit a highly amplified grip on the WE and very low CF cordage may result in force on the return leg of the fixed loop pulling the WE out of the turNip.

This defines a structure, and a loading pattern, and limits the scope of operation beyond which the knot is no longer considered to be a Bowline.

But in making the description, we had to declare 'heavy ring loading'  - this immediately exposes the description to the demand for a definition of 'heavy ring loading' - what deformation has to take place before the Bowline is no longer...?

OR

The Bowline (#1010) is a fixed loop knot comprised of two components, the turNip Component and the Bight Component, configured as the SbC.
SP load is applied to the collared turNip leg.
The fixed loop is applied to the remaining turNip leg and one of the nipped Bight legs.
The remaining Bight leg is left unused.



They both describe the #1010, but neither offer an acceptable level of expansion or enhancement to encompass what I consider to be an as yet, undefined characteristic of a family of Bowlines, i.e. does such a family all have to have the #1010 at their core i.e. #1010 +++  or is there some other elemental Bowlinesque characteristic that screams BOWLINE...?

Derek

Dan_Lehman

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #316 on: January 17, 2016, 07:31:04 AM »
I want my #1010 to remain a #1010 under all usage loadings ...
And right here you've made a leap that leaves
me turning another direction --I'm not with you.
Loadings matter, and IMO are *definitional*
--and in the realm of "theory",
and, understandably, not so handy to knock about in
parlance of practitioners (though I'll wager that they
can understand the point about such differences, and
that one sometimes engages "ways of speaking" that
aren't meant for profundity or tight consistency).


Quote
First, we are not dealing with a Theory here, [but]
we are attempting to define working descriptions for the purpose of classification.
IMO, definitions such as these should be seen as in
the realm of "theory".  After that, some way of converting
that to common parlance can be sought.

Quote
A Bowline (for which the default knot is #1010) is a fixed loop knot.
"fixed loop" irritates me on two grounds:
1) I favor "eye", as previously advocated, and
2) eye knots are by definition "fixed" --otherwise,
I think what one has should be called a "noose"
which is not a *knot* but a *knotted structure*.

Quote
The Bowline is not stable under heavy ring loading when
it will morph into a variety of forms eventually ending in a noose.
Grammatical point :  "when" can be read as restrictive/qualifying
or non-restrictive (explanatory) --i.e., that it points something
that might or rather is bound to happen; not sure
that a comma clarifies this, either.

But I'm more intrigued by what you think will happen!!  ::)
Care to elaborate --name names-- on these morphed-into forms?!
(Hint : the risk is NO forms!)

Quote
But in making the description, we had to declare 'heavy ring loading'
... and fantasize morphistations !!   ;D
(Did you fix that loop around your neck?)
((I'm having TOO much fun w/this.  ;D ))
(((The pile-hitch noose btw is what results from some
heavy loading of the paradigm bowline --and which is
indicated in that fellow's assertion quoted by Ashley, even
"back in the day" !  And, no, it doesn't always happen.)))

Quote
The Bowline (#1010) is a fixed loop knot compRIsed of
two components, the turNip Component and the Bight Component, configured as the SbC.
SP load is applied to the collared turNip leg.
The fixed loop is applied to the remaining turNip leg and one of the nipped Bight legs.
The remaining Bight leg is left unused.
[I must react to "comprised of", which I say is simply
invalid syntax!  (There are quite good, complementary
uses for comprise, compose, include, ... which should
be fought for, staving off the decline to ... "yaknowhatImean"
grunts dependent fully upon context for sense!  GRRR
]
My sense of what is being said or sought to be said above
is The bowline is an eye knot in which the main load(ed strand)
makes a full turn around --and thus secures-- other parts
of the knot which work to maintain the integrity of this turn.

Perhaps if I leave out specification for what the main strand
(S.Part) does after the "full turn" I allow for the double & water
bowlines
while precluding the fig.8 --a "full turn" being
one that sends the line on in the direction aimed at before
the turn (whereas in the fig.8 it's not full, but a U-turn)!?

But I was waiting to hear how Derek dealt with the fig.8
per his seemingly accommodating view of the turNip vis-a-vis
loading the "ongoing eye leg" or must clamping it.


--dl*
====

DerekSmith

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #317 on: January 17, 2016, 11:33:13 AM »

 The bowline is an eye knot in which the main load(ed strand)
makes a full turn around --and thus secures-- other parts
of the knot which work to maintain the integrity of this turn.


--dl*
====

Is that the entirety of your definition for the Bowline Dan?  That is, anything that fits that definition is a Bowline?


Dan_Lehman

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #318 on: January 18, 2016, 06:55:28 AM »
Quote
Is that the entirety of your definition for the Bowline Dan?
That is, anything that fits that definition is a Bowline?
Ah, no, it can't be --the conflict of specific vs. general
as highlighted.  I started off just wanting to restate
your words without the "component" terms, and so
was taking a definition of THE ... but then lost train of
thought (or simply wasn't paying close attention!) and
ran off with the idea of a generalization that might serve
to judge *genus* of knots (as was the general thrust of
this thread) --indicated by my remarks following.

So, for "the..." I'd simply describe the collaring bight, yes.
But looking towards "a..." I open things up.  (And seeing
what might thus fall into this generalization, there might
be amendments & expressions of regret or deep sighing.)


--dl*
====

knotsaver

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #319 on: January 18, 2016, 03:30:33 PM »
Well, that really is quite amazing.



I have confirmed that the Myrtle C Component at the heart of this Myrtle Loop knot is a 5,1.

Yet only one tiny modification is necessary to destroy this, and render it into the Unknot.

It is not the collar, nor the tuck under the collar.  Just the action of passing the end back into the nip, means that this knot can then be be TIB.

Well done Xarax...  I bow to your observation.

However, have you been able to reverse the reversal, and create the knot 'In Bight' so to speak?

Derek

Hi Derek and hi all,
look at the picture (TIB.jpg) for a TIB method.
If we change the insertion of the eye/bight/loop (?! this is not the thread to use wrong term  :-\ ) in 4th frame as illustrated in the picture TIB_eye_method.jpg we obtain a (new?) TIB knot, look at the following pictures TIB_eye.jpg and TIB_eye_loose.jpg
Ciao,
s.

DerekSmith

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #320 on: January 18, 2016, 07:39:41 PM »
Quote
Is that the entirety of your definition for the Bowline Dan?
That is, anything that fits that definition is a Bowline?
Ah, no, it can't be --the conflict of specific vs. general
as highlighted.  I started off just wanting to restate
your words without the "component" terms, and so
was taking a definition of THE ... but then lost train of
thought (or simply wasn't paying close attention!) and
ran off with the idea of a generalization that might serve
to judge *genus* of knots (as was the general thrust of
this thread) --indicated by my remarks following.

So, for "the..." I'd simply describe the collaring bight, yes.
But looking towards "a..." I open things up.  (And seeing
what might thus fall into this generalization, there might
be amendments & expressions of regret or deep sighing.)


--dl*
====

Dan, can you help me out here.

I am trying hard, honestly I am, but I am struggling to understand this last post.

Could you have another go at rephrasing for me please - sorry for being a thickie.

Thanks.

Derek

DerekSmith

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #321 on: January 18, 2016, 07:44:10 PM »
Hi knotsaver,

as a cerebral exercise, that is a great solution.



One thing it tells me though is - if I want a midline loop, I would be best to stick with the Alpine Butterfly

Well done tho'

Derek

Dan_Lehman

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #322 on: January 19, 2016, 12:39:02 AM »
Dan, can you help me out here.
I am trying hard, honestly I am, but I am struggling to understand this last post.
Could you have another go at rephrasing for me please - sorry for being a thickie.
Hmm, okay.
My main point was that there is a contrast in these
"definitions" between having one that is particular
to the bowline vs. one that is more general, that
serves for determining a bowline --for constituting
the "genus bowlinenus" (to sound scientific [no, I'm not Latin]).

And that I'd simply begun my writing in thinking to cast
your definition in sort of straightforward terms (vs. those
of your "component" terminology), and then mid-way
into this I just left off without the specificity of your
definition --which I think might be to just #1010, if
not that and allowing the "left-handed" version (but
SBComponent I think is taken as "same-side" version,
which is specific).
So, I ended up with --as you asked-- a recipe (perhaps)
for constituting the set of bowlineS --#1010 and friends.
Because after specifying the central nipping loop, I allow
whatever else completes the knot so long as it maintains
the integrity of that loop.  And I suggested that my
definition, e.g., allows the water & double bwls., as they
in different ways continue from the nipping loop
--the latter by repetition of turning and the former
in repeating the loop (i.e., making a 2nd one).  And the
Myrtle qualifies in that it maintains the integrity of
the loop, too.

Although we can see cases in which loose dressing and
great forces (maybe elastic material is all the more
deformable and thus problematic, geometry morphing)
challenge "the integrity of the (central nipping) loop"
to various degrees --threatening to become a helix or
worse (capsizing)!  <sigh>


--dl*
====

DerekSmith

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #323 on: January 20, 2016, 12:32:53 PM »
Thank you Dan for your patience.  I now understand, and going back to your previous post, I see that is exactly what you were describing.

To make things slightly easier for me (I have a problem calling anything other than #1010 a Bowline), might I suggest that we drop the term Bowline for the moment, and concentrate on assembling a set of characteristics that includes #1010.  Eventually, you might choose to call this set the Bowline Set, but in getting there it might prove advantageous to forget names and simply look for group characteristics.

There are many ways of listing the characteristics that are required for membership of this set.  One way was from the purely operational direction I offered in the previous descriptions.

A working knot - i.e. it handles load
A fixed loop knot .
Containing the SbCore loaded as per #1010

But as Dan points out, this is too restrictive a description because the set only contains one member - #1010.

In contrast, Dan has offered a more encompassing set (if I might paraphrase) :-

A working fixed loop knot
Containing a stabilised turNip component loaded between the SP and one loop leg.

This set encompasses #1010 together with a significant array of other turNip containing fixed loop knots.  This set might legitimately be called the turNip Loop Knot Set - or, because it contains #1010 you might even be comfortable in calling it the Bowline Set, even though it might contain knots that challenge any sensible association with #1010 and could just a s legitimately be called the Myrtle Set...

I think the point here is, being a member of the turNip Loop Knot Set, is exactly that, and nothing else - it does not mean that a member of the set is a Bowline.  Rather, it is a member of a set that shares some of the characteristics / properties / methods etc. of the Bowline.

Yet others have defined the set as :-

A fixed loop knot with a collar around the SP.

Again, it is a completely legitimate set, and we could call it (amongst many other names) the Bowline Set.

But this leaves me with questions: -
WHY?
What have we gained by describing these sets?
What can we infer or project about members of these sets from the set characteristics?

It seems to me that we are falling into the realm of the kiddies colouring book, seeking pretty patterns - just because they look nice.  We are at risk of pushing working knots into the blasphemy of Decoratives...

Or is there a practical reason for seeking a rational Set that includes #1010?  If such a reason can be identified, it might point more clearly to the characteristics we need to identify in order to define the Set.

Derek

Dan_Lehman

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #324 on: January 20, 2016, 08:28:00 PM »
(I have a problem calling anything other than #1010 a Bowline)
Even Ashley's #1034.5 ("left-handed"/tail-outside bowline) ?!


Quote
But this leaves me with questions: -
WHY?
What have we gained by describing these sets?
What can we infer or project about members of these sets from the set characteristics?
X. would respond that the point (should be obvious; "I must say again...")
is to have knots that don't bind (such as an overhand-based one
might) and don't *linger* upon untying (such as leaving a fig.8
after pulling out the tail part, and then ... SOMEtimes it has
caused careless rockclimbers problems, pulling this end-w/knot
line and getting it stuck --oops/curses).

But I suspect we can find jamming knots that fit the definitions,
and things that aren't quickly tied, and so on.

Quote
Or is there a practical reason for seeking a rational Set that includes #1010?
If such a reason can be identified, it might point more clearly to the characteristics
we need to identify in order to define the Set.
Yes, as just noted : sure grip & quick tying & easy
untying & decent strength ... --are sometimes-#1010
qualities sought in derivatives.  And the left-handed bwl.
and "carrick loop" bwl. #1033 deliver these, both with
more resistance to capsizing, IMO.

But can one write a definition that ensures such qualities
in qualifying knots?  --or doesn't get bogged down in the
reality of materials & forces ... ?!
Probably not, but maybe the effort to form such a group
at least gives a reasonable set of things to offer for those
wanting such qualities, neverminding that the set should
be seen as stocked with much else.


--dl*
====
« Last Edit: January 21, 2016, 05:28:56 PM by Dan_Lehman »

DerekSmith

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #325 on: January 21, 2016, 10:14:33 PM »
oted : sure grip & quick tying & easy
untying & decent strength ... --are sometimes-#1010
qualities sought in derivatives.  And the left-handed bwl.
and "carrick loop" bwl. #1033 deliver these, both with
more resistance to capsizing, IMO.

But can one write a definition that ensures such qualities
in qualifying knots?  --or doesn't get bogged down in the
reality of materials & forces ... ?!
Probably not, but maybe the effort to form such a group
at least gives a reasonable set of things to offer for those
wanting such qualities, neverminding that the set should
be seen as stocked with much else.


--dl*
====

It seems to me that this is starting to go in a circle - picking knots to define the group.  Not particularly useful as a tool to project characteristics, or propose 'missing' combinations.

Also, depending on how you draw #1033 up, its most stable form (drawing up the SP and its opposite corner loop leg) is a Carrick input component, stabilised by a turNip between a loop leg and the WE  (i.e. the SP does not feed the turNip, which is only loaded one side...).  This would fail just about all the proposed characteristics of a member of the Bowline Set.

Shame really, because Fixed loop knots which start with the load entering via a Carrick Component are generally strong, stable, and esy to untie.

Derek

Derek

DerekSmith

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #326 on: January 22, 2016, 12:30:06 AM »
I just went back to the original document and spotted that by the Set descriptors now being used, the three knots on page 10 fail to belong.

The first is the Myrtle, it does not have a loaded collaring bight, instead it has a second turNip (plus, I think the image is of one of the 'false' Myrtles, this one I think has two 'S' twist turNips instead of an 'S' and a 'Z' - can you check pls. Dan.).

The second is the Eskimo, which as soon as it is loaded dresses itself correctly as a Carrick input Component.

And the third, although it has the correct loaded bight collar, the nipping turn has been replaced by a Carrick Component.

One step forward, two steps back...

Derek

Dan_Lehman

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #327 on: January 23, 2016, 03:07:25 AM »
as noted : sure grip & quick tying & easy
untying & decent strength ... --are sometimes-#1010
qualities sought in derivatives.  And the left-handed bwl.
and "carrick loop" bwl. #1033 deliver these, both with
more resistance to capsizing, IMO.

But can one write a definition that ensures such qualities
in qualifying knots?  --or doesn't get bogged down in the
reality of materials & forces ... ?!
Probably not, but maybe the effort to form such a group
at least gives a reasonable set of things to offer for those
wanting such qualities, neverminding that the set should
be seen as stocked with much else.


--dl*
====

It seems to me that this is starting to go in a circle - picking knots to define the group.  Not particularly useful as a tool to project characteristics, or propose 'missing' combinations.

Also, depending on how you draw #1033 up, its most stable form (drawing up the SP and its opposite corner loop leg) is a Carrick input component, stabilised by a turNip between a loop leg and the WE  (i.e. the SP does not feed the turNip, which is only loaded one side...).  This would fail just about all the proposed characteristics of a member of the Bowline Set.
This just shows some bias of familiarity/unfamiliarity :
the bowline --our seed exemplar, here-- can also be cast
as a "carrick component"'d knot --just SS369 it as you suggest
for #1033.  Yes, loading works against even such hard-set
tying, and the "carrick component" thus realized is reversed
in orientation (S.Part has in one what "ongoing eye leg" has
in the other, of this "carrick component"), but still, it's all there.

(To see this in the bowline, you might try setting by pulling
ongoing eye leg vs. tail --yeah, hardly normal, I know.
But I suggest this because doing the same --same parts,
but more naturally positioned for such opposition--
with #1033 will set things quite nicely for a *bowline*
--which I only just realized in considering this post!
(Hmm, well, one can go too far in this setting; doing it with
some moderation, though, has the effect of drawing down
the (half-)collar around the S.Part, and cannot fold the
ongoing eye leg into the "carrick component" position
--but going too far will do that to the S.Part!)
)

In short, one must realize that the bowline (#1010) has
this quite-UNsnugged "collar" bight, as we call it.  And
that is so ingrained in us that we might be overlooking
the oddity of it, as we elsewhere want to snug things
up into "most stable" forms, and so on.

As for determining the group by some "*seed*" knot,
or working the other direction --of having a group in
mind after collecting desired fruit--, it gets back to one
of the fundamental questions, about the whole point
of such classification; about how one wants "to speak
of ... things", and so on.

I'm at least happy enough to let ideas develop in an
iterative manner of proposition, seeing what follows,
and tailoring refinements based on desire.  In that I
surmise that we are building a sort of *tool* and not
mining Trvth.   :)
But we should already realize at this point that the
vagaries of setting and geometry changes via that
and forces upon various materials makes cataloging
knots by geometrically determined/defined components
a challenge, to say the least.  I've suggested "appearances"
in hopes that some canonical point of assessing these can
lead to some reasonable classification, even admitting that
in practice, significant changes can occur --the "loop" can
be opened into a "helix" or folded into a "carrick comp."
and so on.  I don't think we can do much about that
other than recognize it.


Btw, re snugging up the bowline et al or not ::
I have various small cords tied to my keys ring
(in theory for occasional knot fiddling or use; in practice,
I don't like to mess with these and have other bits of
cordage for use), and the main one --of small binding
cord (hollow braid nylon)-- is joined with a zeppelin
bend
, for decades(!!).  The small (3/16"?) solid-braid
nylon ("hardware store")  cords have had moderately
well-set grapevine bends loosen, and most recently it
was an offset 9-Oh that has now twice/thrice loosened.
So, I thought about how IMO the mirrored bowline
--that "Janus'd" variation with a larkshead base--
although not set tight (not "SS369'd") nevertheless seems
resistant to loosening much, and so I tied a corresponding
twin bowlines bend --one with each tail reeved through
both turNips.  Seems darned loose, yet no looser than tied;
now to see how long it so endures ... .

--dl*
====

ps : no "20-30inches" of snow, YET; but my world is whitened.
« Last Edit: January 27, 2016, 06:05:39 AM by Dan_Lehman »

DerekSmith

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #328 on: January 24, 2016, 11:53:50 AM »
A chap called Wordsworth once wrote --

"For oft, when on my couch I lie. In vacant or in pensive mood,. They flash upon that inward eye. Which is the bliss of solitude;"

Well, I don't know about the Daffies or the couch bit, but I can certainly accord with that 'flashes upon that inward eye' moment.  Bron has often come crashing through my mental cogitations with - "Derek ! are you twiddling again ? ? ?  Isn't it time you got on with -------- (insert any item from 'The List of Things that Women Think are Men's Duties')".  And yes, I was probably sitting there with a  vacant expression on my face and a favourite length of twiddling cord in my fingers...

And what was I doing?  Yes, you got it, I was Knot Bothering....  I am a Knot Botherer...  and I think, on this Forum, I am in good company.

That was perhaps a tedious preamble to get to the point that fellow KBs will all be totally aware of the fact that we can take virtually any knot, and after a bit of twiddling, transform it into any desired form plus a tangle.  Yes, I can rework a #1010 into a Carrick component plus a tangle.  I can go yet further and work the #1010 into a Noose plus a tangle.  I can take the simplest of completed knots - the OH Knot - and with the minimum of change, I see it is but the Carrick Component with a tucked tail.

But - if I dress and set a #1010 I do not get a Carrick Component, and if I dress and set a #1033 into its most stable form, I get the SP leading straight into a Carrick Component.

Our dilemma, I would suggest, is that as KBs we both know that a totally different knot is only a twist and a flick away...  Yet, although this transform might only be subtle, it means the death of one knot with the creation of another.  As the turNip in #1010 gently elongates, the Fixed Loop Bowline is destroyed and a Noose is born in its place.

You and I know these transforms are so close, so subtle, so hard to ignore, but I would suggest that the knot does not know this...  it only knows what it is and in order to find as simple a means of classification as possible, I would suggest that we have to see the knot 'as it is' and not as 'what it might be'.  We need to turn a blind eye to our knowledge of 'what might be' and adopt the KISS approach.

#1010 as it is intended to be, meets our definition of belonging to the Bowline Set.
#1010 as it might become, does not meet our definition and does not belong to the Bowline Set.
#1033 in its simplest and most stable form does not meet our (present) definition, and so does not belong to the Bowline Set.
Eskimo Bwl. does not meet the (present) loading pattern, and so does not belong to this Set.

Having said that, I have to fully agree that this Set Definition we are constructing, is not some Fundamental Truth, rather, it is simply an agreed set of characteristics which might allow us to draw some common characteristics about its members and perhaps, map in 'missing' members.  But then, as we have not even agreed a purpose for such a Set Definition, we could just a easily ignore the 'working knot' aspect and declare the Set to include any knot that looks remotely Bowlinesque, has ever been called a Bowline, or any of a myriad of subjective aspects.

My personal preference would be to start with a reasonably simple and essentially rational  definition such as the one already outlined based on the SbC and a defined loading pattern, then see what problems it creates and work from there...

PS - what is SS369ing
PPS - I hope you are well stocked with provisions - it looks pretty grim in your 'neck of the woods'.

Derek

agent_smith

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Re: Analysis of Bowlines paper uploaded for review and comment (PACI website)
« Reply #329 on: January 26, 2016, 04:34:47 AM »
Speaking of Carricks...

Quote
#1010 as it is intended to be, meets our definition of belonging to the Bowline Set.
#1010 as it might become, does not meet our definition and does not belong to the Bowline Set.
#1033 in its simplest and most stable form does not meet our (present) definition, and so does not belong to the Bowline Set.
Eskimo Bwl. does not meet the (present) loading pattern, and so does not belong to this Set.

I'm not sure that I entirely agree.

Clearly, a fundamental property of a Bowline is that it is an 'Eye knot'. If there is no 'eye' - it is automatically ruled-out as a Bowline.

There must also be a nipping structure (ie nipping loop - or you seem to like the term 'turNip' which I should point out was disliked by many on this forum). In my personal view, there are 2 further qualifying requirements:
1) The 'nipping structure' must have a compression zone - and where there is no compression, it is non-functional and therefore ineffective; and
2) The 'nipping structure' must be loaded at both ends.

So for me, the Sheet Bend (#1431 ) does not have a functional 'nipping loop' - as it fails to meet the qualifying elements.

I am also of the view that there must be a 'collar-capstan' structure. Indeed, if this structure is absent - it again automatically disqualifies it from being a Bowline. A further qualifying requirement is that the 'collar' must form around the SPart. If it forms around an eye leg instead of the SPart (eg an 'ongoing eye leg') - this earns it the title of 'Anti-Bowline'. So the badly named 'eskimo' bowline is an 'anti bowline'. So the difference between a Bowline and Anti-Bowline is with respect to where the 'collar-capstan' is formed.

...

An example of a non-functional (ineffective) 'nipping loop' is with the Carrick eye knot (#1439 derived) prior to being transformed.

Compare the transformed image - Carrick Eye knot #1439 derived - does this structure have a functioning (effective) 'nipping loop'?

It has similar form to a munter hitch - and indeed reminds me of the nipping structure in the 'Karash loop / eye knot' in its single eye form.

Another interesting point is that the 'collar-capstan' is not formed around the SPart...it is formed around an eye leg - in this case the 'returning eye leg' - similar to an 'anti-bowline' (aka poorly named 'eskimo bowline'). Although I should point out that in the 'anti-bowline' - the collar forms around the 'ongoing eye leg' and not the 'returning eye leg'.

And of course - does the Karash eye knot have a functioning 'nipping structure' (ie to be functioning and effective - it must have a compression zone)?

Edited: Grammar and text changes to make it clearer...
« Last Edit: January 26, 2016, 05:13:11 AM by agent_smith »

 

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