Author Topic: ABoK 1408, 1409 & what it means for the Ashley Bend  (Read 16681 times)

roo

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ABoK 1408, 1409 & what it means for the Ashley Bend
« on: June 25, 2010, 10:35:45 PM »
Quote from: jcsampson
ABOK #1408 appears to be somewhat related to the Zeppelin Bend's design--if you do not cross the tails as shown in the diagram. What do you think of this ABOK #1408?
To my eye, it looks much more like a minor variation on the so-called Ashley Bend.  I've attached an image so others know what you're referring to.  Reading a little further in the Ashley Book of Knots we find something of interest:

1408: Here is another bend with the same untrustworthy features as the "Whatnot", yet in the form shown here it ranks among the securest of bends known.

1409: But in this second form it is one of the least secure knots known, its only rival being the Whatnot.  The change from one of its forms to the other may occur accidentally or intentionally.  So the knot is quite untrustworthy.


Tying this in more elastic material, you get a dramatic demonstration of what Ashley is talking about.  It rolls apart. (Update:  I also had such a single-pull rollout experience in some twisted polypropylene loaded only by hand.  The rolling action destroyed the twist of part of the rope.)

So it becomes quickly evident why 1408 and its shifted form in 1409 are neglected.  

This has implications for the Ashley Bend that I did not consider before.  It is a very easy error to mistie the Ashley Bend and get the scary 1408/1409!  They even look like the Ashley Bend.  For 1408/1409, the "q" initially goes through the "b" from above.  For the Ashley Bend, the "q" initially goes through the "b" from below.  

Poor Ashley; getting his name tacked to a bend in a way he might not appreciate, especially considering this relationship.

cf:  
http://notableknotindex.webs.com/butterflybend.html
http://igkt.net/sm/index.php?topic=1892.0
« Last Edit: July 12, 2010, 07:28:04 PM by roo »
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knot4u

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #1 on: June 25, 2010, 11:05:10 PM »
Thanks, I'll continue to ignore these knots.

jcsampson

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #2 on: June 26, 2010, 02:18:46 AM »
Quote from: roo
"It rolls apart."

Ah, now I understand the relationship between #1408 and #1409. Ashley wasn't exactly clear about this. The diagram for #1409 shows one tail crossing over the other in a way that is opposite to that for #1408. I tried #1409 and saw that it rolls, but Ashley didn't explain clearly that tying #1408 could easily enough shift into #1409--and roll.

I made #1408 looking only at the very first of the two diagrams and tightened it without any crossing, and it appeared to hold well. Then, I tried to figure out what Ashley was getting at, with respect to the crossing tails and saw that #1409 does in fact roll. It rolled almost as easily as a Granny.

Yup: Knots that roll or MIGHT roll will have to stay off the menu.

It seems that #1408/9 has a "design flaw," and that the Zeppelin Bend has REMOVED this flaw, so that what does remain with the Zeppelin Bend could very well be the part that results in "the securest of bends known."

Quote
"Poor Ashley; getting his name tacked to a bend in a way he might not appreciate, especially considering this relationship."

Well, since he said, "Make only one change . . . and either an entirely different knot is made or no knot at all may result," he's officially off the proverbial hook.

Don't tell anyone this, but I recently made an Ashley Bend and found it to be even more diagonally lopsided than the Zeppelin Bend. I'm afraid that the Ashley Bend will have to stay off the menu, too.

JCS

roo

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #3 on: June 26, 2010, 04:09:46 AM »
Quote
"Poor Ashley; getting his name tacked to a bend in a way he might not appreciate, especially considering this relationship."
Well, since he said, "Make only one change . . . and either an entirely different knot is made or no knot at all may result," he's officially off the proverbial hook.
I never really thought of him as being on the hook.  I'm not sure what he'd be on the hook for.

Quote
Don't tell anyone this, but I recently made an Ashley Bend and found it to be even more diagonally lopsided than the Zeppelin Bend.
Could you clarify what you mean by "diagonally lopsided"?
« Last Edit: June 26, 2010, 04:10:52 AM by roo »
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Dan_Lehman

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #4 on: June 26, 2010, 05:03:41 AM »
At the risk of violating the old maxim Where ignorance is bliss,
'tis folly to be wise,
this post begs some obvious questions and redress.

Quote from: jcsampson
ABOK #1408 appears to be somewhat related to the Zeppelin Bend's design--if you do not cross the tails as shown in the diagram. What do you think of this ABOK #1408?

You have a good eye; but this version/dressing of #1408 doesn't
perform all so well, as it both worryingly sucks in tail and rolls out
material in some slippage, and in doing so makes its collars tight,
so loses the very aspect that a properly dressed #1408 is to provide.

With the correct dressing, the collars have an openness like that
of Rosendahl's bend, and the knot loosens easily.

To my eye, it looks much more like a minor variation on the so-called Ashley Bend.

Indeed it has much similarity to #1452, with the interlocking of the SParts
and nipping of tails brought together up through the SParts' joint nip.
"So-called" "Ashley's Bend" comes from CLDay, a friend, and has been
adopted by the echo chamber thereafter.  As it's not his only end-2-end
knot, I usually follow the moniker with the number (and might sometimes
have another number, for some other of his knots).  And "Zeppelin" (not
sure re "bend" vs. "knot") comes apparently from some magazine-article
authors (or even merely a headline writer!), with no apparent competing,
original name (unless that interviewed subordinate referred to it by
"Rosendahl" ?).


1409: But in this second form it is one of the least secure knots known, its only rival being the Whatnot.  The change from one of its forms to the other may occur accidentally or intentionally.  So the knot is quite untrustworthy.

One might wonder at "intentionally" !  As for security, I've just put some serious
load on a couple ropes with this dubious version and had it hold -- rather hard
and slick PP, kernmantle (monofilament) & laid.  In shock cord --ha!-- it hardly
slows down (spilling), giving a lot of torque to the feeding-out material.
--as you note:
Quote
Tying this in more elastic material, you get a dramatic demonstration of what Ashley is talking about.  It rolls apart.

But this is a non sequitur:
Quote
So it becomes quickly evident why 1408 and its shifted form in 1409 are neglected.

Much/most of ABOK is neglected --surprisingly, to my mind, Ashley's
stopper--, and one can only wonder why (even if good reasons exist).

Quote
This has implications for the Ashley Bend that I did not consider before.  It is a very easy error to mistie the Ashley Bend and get the scary 1408/1409!  They even look like the Ashley Bend.  For 1408/1409, the "q" initially goes through the "b" from above.  For the Ashley Bend, the "q" initially goes through the "b" from below. 

WOW, so easy to do this, huh!!!  But doesn't this fear also d-q your Zepper?


Quote
Poor Ashley; getting his name tacked to a bend in a way he might not appreciate, especially considering this relationship.

Maybe the modern detection devices can check whether
he's turned over in his grave.  (But then would we know it
was over this fear?)

--dl*
====

roo

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #5 on: June 26, 2010, 07:08:06 AM »
But this is a non sequitur:
Quote
So it becomes quickly evident why 1408 and its shifted form in 1409 are neglected.
I think it very much follows that people leave problematic knots alone.  When you have as many knots listed as Ashley does, most of them are going to have serious or at least significant drawbacks, as Ashley himself points out.

Quote
Much/most of ABOK is neglected --surprisingly, to my mind, Ashley's
stopper--, and one can only wonder why (even if good reasons exist).
??? Why would you wonder about neglect due to good reasons for that neglect?

Quote
But doesn't this fear also [disqualify] your Zepper?
Quite the opposite.  I find it extraordinarily hard to botch a Rosendahl Bend and end up with something that looks like the real article while being otherwise deficient or problematic.  I seriously think it could be impossible for a novice (or perhaps anyone) to do.  Indeed most common or easy botches end up in near nothingness and couldn't reproduce the perfect and distinctive point symmetry of the Rosendahl Bend that is clearly apparent on both sides.

Give it a try.  It's a very good challenge.
« Last Edit: June 26, 2010, 07:14:38 AM by roo »
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Dan_Lehman

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #6 on: June 27, 2010, 12:33:15 AM »
But this is a non sequitur:
Quote
So it becomes quickly evident why 1408 and its shifted form in 1409 are neglected.
I think it very much follows that people leave problematic knots alone.

While that might follow, it doesn't count as evidence -- just conjecture.
As I said, there is much that is neglected that has not even this
hint of a rationale; and there is the ubiquitous Reverse Groundline Hitch
of commercial-fishing knotting that has been neglected in literature;
here, we have evidence before us of both circumstances.

Quote
Quote
Much/most of ABOK is neglected --surprisingly, to my mind, Ashley's
stopper--, and one can only wonder why (even if good reasons exist).
??? Why would you wonder about neglect due to good reasons for that neglect?

--not what I meant:  we don't know, but only can "wonder" about this.

Quote
Quote
But doesn't this fear also [disqualify]was 'd q', purposefully!} your Zepper?
Quite the opposite.  I find it extraordinarily hard to botch a Rosendahl Bend and end up with something that looks like the real article while being otherwise deficient or problematic.  I seriously think it could be impossible for a novice (or perhaps anyone) to do.  Indeed most common or easy botches end up in near nothingness and couldn't reproduce the perfect and distinctive point symmetry of the Rosendahl Bend that is clearly apparent on both sides.

Give it a try.  It's a very good challenge.

The evidence is already here, I've no need to replicate it; but I did cleverly
point to it with my double-entendre "d q", which you replaced with but
one sense --the other is the point of SPart geometry, and "d q" is the
common enough botching of "d p" orientation.  In my notes where I
first recorded it, having derived it from my first invention, SmitHunter's,
I remark that Percy Bandford has it botched like this in one of his books.
Recently, the same mis-tying was presented by someone in an on-line photo.

"Point symmetry":   as though this is somehow a tying guide to anyone?
Oh, as to symmetry, Xarax, I should think that the Granny has more, as
it's the same knot if ends are swapped w/SParts?!"

--dl*
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roo

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #7 on: June 27, 2010, 12:45:10 AM »
The evidence is already here, I've no need to replicate it; but I did cleverly
point to it with my double-entendre "d q", which you replaced with but
one sense --the other is the point of SPart geometry, and "d q" is the
common enough botching of "d p" orientation.  In my notes where I
first recorded it, having derived it from my first invention, SmitHunter's,
I remark that Percy Bandford has it botched like this in one of his books.
Recently, the same mis-tying was presented by someone in an on-line photo.
I'm not seeing this.  b&q: OK...  p&d: OK... same idea, but d&q or q&d?  How?  Don't your ropes come one from the right and one from the left?  Do you have a picture?

Quote
"Point symmetry":   as though this is somehow a tying guide to anyone?
Actually I was thinking of it more in terms of explaining the nature of the plainly evident, but not quite mirror-like, symmetry in the end product that people use to check the result.

I suppose keeping the general idea of symmetry in your mind could help as a tying guide without explicitly thinking of point symmetry.

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jcsampson

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #8 on: June 27, 2010, 02:30:23 AM »
Quote from: roo
"Could you clarify what you mean by 'diagonally lopsided'?"

Ya.

lop-sid-ed [lop-sahy-did]
--adjective
2. leaning to one side.

di-ag-o-nal [dahy-ag-uh-nl, -ag-nl]
--adjective
2. having an oblique direction.
--Related forms
di-ag-o-nal-ly, adverb

I mean, ". . . leaning to one side . . . in a way that is . . . having an oblique direction."

o-blique [uh-bleek, oh-bleek; Mil. uh-blahyk, oh-blahyk]
--adjective
1. neither perpendicular nor parallel to a given line or surface; slanting; sloping.

- http://dictionary.reference.com/

JCS
« Last Edit: June 27, 2010, 02:32:26 AM by jcsampson »

jcsampson

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #9 on: June 27, 2010, 02:41:11 AM »
Quote from: xarax
". . . we have { L X R } = { ( 2 X 2 X 2 ) X ( 2 X 2 X 2 ) } = 64 possible combinations, 64 possible bends. Many of them are identical, because of the symmetries involved . . . so 64 is reduced to 8."

I like your algorithmic--as shown in some of your previous posts--and combinatorial thinking.

Have you, by any chance, tried Hunter's Bend WITHOUT interlocking and discovered that it comes out sideways? I humorously call this one "The Sidewinder." (It doesn't appear to be very stable or secure, and THIS one genuinely jams.)

I recently tried tying all the popular bends using waxed dental floss. I hate to say this, but they all slipped, with repeated tugs, to some extent. Not that I'll be using waxed dental floss for any application anytime soon, mind you.

JCS
« Last Edit: June 27, 2010, 02:51:33 AM by jcsampson »

roo

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #10 on: June 27, 2010, 04:11:43 AM »
Quote from: roo
"Could you clarify what you mean by 'diagonally lopsided'?"
Ya.
lop-sid-ed [lop-sahy-did]...
I regret asking.  I understand the "leaning" aspect of both "diagonal" and "lopsided".   In earlier context you wrote as the last paragraph:

Quote
Don't tell anyone this, but I recently made an Ashley Bend and found it to be even more diagonally lopsided than the Zeppelin Bend. I'm afraid that the Ashley Bend will have to stay off the menu, too.
You seem to tie this vague "leaning" attribute into rejecting a knot.  Why?
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Dan_Lehman

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #11 on: June 27, 2010, 07:49:28 PM »
The evidence is already here, I've no need to replicate it; but I did cleverly
point to it with my double-entendre "d q", which you replaced with but
one sense --the other is the point of SPart geometry, and "d q" is the
common enough botching of "d p" orientation.  In my notes where I
first recorded it, having derived it from my first invention, SmitHunter's,
I remark that Percy Bandford has it botched like this in one of his books.
Recently, the same mis-tying was presented by someone in an on-line photo.
I'm not seeing this.  b&q: OK...  p&d: OK... same idea, but d&q or q&d?  How?  Don't your ropes come one from the right and one from the left?  Do you have a picture?

Hmmmm, the issue is whether one knot vs. another has some greater
chance of being mis-tied:  I'm pointing to one evidenced mis-tying of
Rosendahl's, as published in a book and on-line.  JCS above I think
points to just this knot as an un-interlocked SmitHunter's variant
(and gratuitously denies the jamming of the same, argued elsewhere).

Quote
"Point symmetry":   as though this is somehow a tying guide to anyone?

Actually I was thinking of it more in terms of explaining the nature of the plainly evident, but not quite mirror-like, symmetry in the end product that people use to check the result.

I suppose keeping the general idea of symmetry in your mind could help as a tying guide without explicitly thinking of point symmetry.[/quote]

But ALL of these knots discussed (except the Butterfly) are symmetric.
The SquaREef is symmetric, but that doesn't preclude one from obtaining
the (more?) symmetric Granny (or Thief, but this takes work).  The *kin*
of Rosenthal's I'll guess are line symmetric -- able to be envisioned
as following the course of a line perpendicular to and bisected by (with
varying length) some reference line?

--dl*
====


[/quote]

roo

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #12 on: June 27, 2010, 09:46:07 PM »
JCS above I think points to just this knot as an un-interlocked SmitHunter's variant

So I think you mean b&d with the non-interlinked Zeppelinesque start.  Let's examine this candidate for an Evil Impostor knot.  I will assume for the sake of argument that b&d is an easy or likely error.

First, as we draw up this knot we notice it radically changes shape in a way that the Zeppelin does not.  Next, as this weird shift occurs the big giveaway occurs.  It sticks out like a sore thumb, quite literally.  I've never seen such a sideways bend.  "Hammerhead" comes to mind.  

We're not done.  There are more giveaways.  Not only do the front and back look different, but as we remove more slack, the free ends often start pointing in the same direction in contrast to the famous cruciform shape of the real Rosendahl bend.   In certain ropes, the impostor eventually becomes truly grotesque in shape.

If this is the best Evil Impostor candidate, then the Rosendahl bend is sitting pretty.   It is such a poor impostor, there's not much point in asking if it is even Evil (insecure or unstable).



« Last Edit: June 27, 2010, 09:48:17 PM by roo »
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jcsampson

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #13 on: June 28, 2010, 12:33:43 AM »
Quote from: roo
"You seem to tie this vague "leaning" attribute into rejecting a knot. Why?"

First, I should say that a more direct way of my describing the situation could simply have been my use of the word "diagonal." But, I wanted to inject (a connotation, which is) my general dislike of knots that are diagonal, so I added the word lopsided (to take advantage of the inherent negative connotation of the word "lopsided") and turned diagonal into an adverb. It seems to work semantically. That's why I looked it up: to verify that it works semantically.

I find that knots that are NOT diagonal and DON'T have the same front and back offer . . . more options--or at least the kinds of options that I can see myself taking advantage of one day. . . . What are those options? Well, I don't have the energy at the moment to expound: It can get complicated. . . .

Let me see whether I can put it in a general way: For all of my knotting life, I have noticed that what I might WANT to do with rope was always more important than what any established knot WAS ABLE do. So, instead of choosing knots because they are known for being one thing or the other, I tend to choose knots that I can see will allow me to do what it is that I might want to do with rope. And, I tend to avoid those knots that I can see might get in the way of what it is that I might want to do with rope. That's how I stumbled upon the Fixed-Gripper Knot: I needed, one day, to meet demands that no established knot could meet, so I experimented and noticed that the result had certain unique properties that I WANTED. As the years went by, I figured out how to exploit those unique properties in ways that I feel are important and would simultaneously allow me to do what I might WANT to do with rope.

See? . . . "complicated."

I hope you don't ask me, "So, just exactly what is it that you want to do with rope?" That's TOO complicated.

Remember that we cannot eat our cakes and have them, too; so, certain properties must be sacrificed for certain others. . . .

JCS

jcsampson

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Re: ABoK 1408, 1409 & what it means for the Ashley Bend
« Reply #14 on: June 28, 2010, 12:46:00 AM »
Quote from: Dan_Lehman
"JCS . . . gratuitously denies the jamming of [Hunter's Bend] . . ."

I recently had a thought about this: I almost always make my Hunter's Bends stopper-flush (by pulling the tails in before tightening). Do you think that this might have something to do with my perspective?

I don't deny--at all--that Hunter's Bend compresses. However:

- I LIKE the properties that compression brings
- The compression allows Hunter's Bend to win the "relative differences" waxed-dental-floss slippage test (This is a controversy, to be sure!)
- Hunter's Bend retains an easy way to decompress the compression, which many seem to constantly ignore

Quote from: roo
". . . the [b and d] impostor eventually becomes truly grotesque in shape."

I notice that the "b and d" imposter knot jams as a result of its becoming grotesque in shape. By contrast, Hunter's Bend compresses, but does not become grotesque in shape. Owing to its eventual grotesqueness, the "b and d" imposter knot retains NO easy way to decompress the compression, and so is a genuine jam.

But if Hunter's Bend really does jam for anyone, then you shouldn't stop using Hunter's Bend--you should stop using thin, stretchy cord!

JCS