Author Topic: What defines a Bowline? - structure, characteristics, topology  (Read 127260 times)

xarax

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #15 on: July 13, 2011, 08:15:54 PM »
Tie an Overhand Knot on a bight....

   Is THAT the way you tie a bowline ? Well, 99,99 % of the bowlines tied each day are not tied that way...because they are used as end-of-the-line loops that :
1., can be tied by using only one end, and after this end has been driven through a ring, (or around a bollard), and
2., can be untied completely by removing the free end from any knot structure on the eye leg of the standing part,  
   If we can not do those two things,, then, of course, we do not have a bowline. But we can tie the Karash bowline that way, can t we ?
« Last Edit: July 13, 2011, 08:17:07 PM by xarax »
This is not a knot.

knot4u

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #16 on: July 13, 2011, 10:28:45 PM »
A lot of noise, dude...

Did you complete my tasks?

A Karash Double Loop is clearly not a Bowline, as explained by the tasks I gave in my last post.
« Last Edit: July 14, 2011, 03:13:35 AM by knot4u »

xarax

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #17 on: July 14, 2011, 12:24:45 AM »
A lot of noise, dude...

   Even the 1/30 th of it, that you manage to read ?  :)
   I had never characterized "noise" what another person is trying to tell me.
   A friendly advice : Some modesty does no harm to anybody. And some doubt about our beliefs/theories.
« Last Edit: July 14, 2011, 12:25:21 AM by xarax »
This is not a knot.

knot4u

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #18 on: July 14, 2011, 08:40:38 AM »
To further drive home my point, watch this video:
http://www.youtube.com/watch?v=6EyfYyJkZss

As shown in the video, you tie the Karash Double Loop by starting with a loosely tied Figure 8 on a bight.

Now, try this.  Instead of starting with a loosely tied Figure 8 on a bight, start with a loosely tied Figure 10 (Stevedore) on a bight.  Then, finish the knot as shown in the video.  If you are putting a Karash Double Loop in the Bowline family, then you also must put this knot I described in the Bowline Family.  If you continue with this same line of thinking (Figure 11, Figure 12, etc.), then the number of knots you must now include in the Bowline family is theoretically infinite.

That's absurd.  Let's not be absurd.
« Last Edit: July 14, 2011, 08:48:39 AM by knot4u »

agent_smith

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #19 on: July 14, 2011, 10:50:50 AM »
This thread is about what defines a Bowline.

From knot4u:
Quote
You cannot tie a Karash Double Loop if you begin as if you are tying an overhand knot (on a bight), but you CAN with every Bowline mentioned on this page:

and also:
Quote
you tie the Karash Double Loop by starting with a loosely tied Figure 8 on a bight.

I wanted to point out you do NOT need to begin from #1047 (figure 8 loop) to tie a Karash.

You can tie the karash by forming an overhand loop (doubled or 'on-the-bight') and then following the tying method depicted at #1080 and performing a 'backflip' maneuver.

However, after initially forming the overhand loop, you then need to induce an extra twist (or 180 degree U turn) by folding the working end back on top of itself (sort of like a Munter hitch on a double strand). Then you perform the #1080 backflip maneuver.

I think you are referring to #1081 and #1082 - which depict the use of an overhand loop on the bight as a starting point to arrive at a bowline on the bight. Both methods involve a 'backflip' maneuver however.

If I am understanding you correctly, your criteria is as follows:
All [double] Bowlines can be formed by starting from #1009.

My next step is to see if there is a way of tying the karash double loop from #1009. A theory is a 'proposed explanation' (or an "established explanation accounting for known facts or phenomena")...and all theories must be able to withstand attempts to prove otherwise.

Derek (the dunny man), what rationale are you using as the basis for your proposition that the karash is a Bowline variant? I thought your colored ropes idea had merit...

Mark
« Last Edit: July 15, 2011, 01:32:26 AM by agent_smith »

TheTreeSpyder

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #20 on: July 14, 2011, 01:37:40 PM »
To me, a Hitch made to line itself on a single line is a Half Hitch (in perpendicular pull on spar form).  But this Half Hitch, made to a bight/ eye is a SheetBend / Becket.

Can also have a Half Hitch pulling inline on spar (if slid off end leaves no knot); but makes Marl(if slid off end leaves OverHand Knot) if Half Hitch perpendicular pull form is used and free end just pulled.

Bowline, is then a SheetBend to self to form fixed eye.

BoB, does same on bight by sneaking an inversion in the back door, but must be sure to complete the inversion until Standing is deformed into Half Hitch locking into bight/eye of the end of the bight of the whole arraingemeant.

Karash would seem to give similar inversion, but not from OverHand (as in BoB); but rather fig.8.  Must still make sure to carry the inversion all the way across to deforming the Standing into more of a fig.8 Hitch (Abok 1666) SheetBend to self.

Weather using a 1666 in place of a 1662; because it is more towards a better Nip of 1663(more ref. thru 1707) + more Frictions; disqualifies the form as a Bowline, i really can't say.  Except that the main change in the mechanic is more of a fig.8 Hitch than Half Hitch as locking Nip formed from Standing's immediate tensions.

Line can only resist/ support on the inline axis, and then only in the tension direction.  A line is strongest/ at potential strength when totally inline / straight; but mostly must be bent/ deformed from optimal straight to be used.  There are only so many of these base bends/ deformities possible; and they should be named and mechanically understood.  Also, should see same lacing as different mechanic / name per direction of force/pull/ flow on lacing.

One of my favorite strength retention references in Abok is 1669.
« Last Edit: July 14, 2011, 01:45:23 PM by TheTreeSpyder »

xarax

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #21 on: July 14, 2011, 03:06:03 PM »
Bowline, is then a SheetBend to self to form fixed eye.

   TheeSpyder, it shows that you have gone to school, together with Derek Smith !  :)
   As I have already argued at Replies #2 and #6, this theory is falsified by the simple fact that a Bowline can hold even when the collar is very loose, while the Sheet bend can not.
   Have a look at ABoK#160 and ABoK#161. Do you see any elements of the Sheet bend there ? Do you see any elements of any hitch whatsoever ? Do you see segments of lines perpendicular to each other, as in the Sheet bend ? No ! But you see elements of the Bowline, of course ! And you see elements of the Bowline in the Gleipnir, too, which is nothing but a bowline-type of knot, where the capstan advantage of the collar has been replaced by the mchanical advantage of the second line.
   The false theory of the close relation of the Bowline with the Sheet bend was, in fact, initiated by Ashley, who had not paid much attention to ABoK160 and ABoK#161 as structures that could evolved even further : that is why he missed the Gleipnir ! Had he met the Gleipnir, I am sure that he would have seen its close relation with the Bowline, at once.
   The Gleipnir proved that the primary element of the Bowline is the nipping loop, and the secondary element the collar. If we did not know the Gleipnir, ( and the ABoK#160 and ABoK#161 ), we would be justified to see the relation of the Bowline with the Sheet bend, indeed, a relation that is more remote and less important that the relation between the Bowline and the Gleipnir.
This is not a knot.

knot4u

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #22 on: July 16, 2011, 02:41:43 AM »
I wanted to point out you do NOT need to begin from #1047 (figure 8 loop) to tie a Karash.

You can tie the karash by forming an overhand loop (doubled or 'on-the-bight') and then following the tying method depicted at #1080 and performing a 'backflip' maneuver.

However, after initially forming the overhand loop, you then need to induce an extra twist (or 180 degree U turn) by folding the working end back on top of itself (sort of like a Munter hitch on a double strand). Then you perform the #1080 backflip maneuver.

That's a slight of hand to avoid the issue...

Let's talk about single loops.  Tie a loosely tied Overhand.  Now, without without completely untying the Overhand, can you tie a Karash Single Loop on that Overhand?  I don't think so.  But I can tie other knots I know to be Bowlines.  Also, if I start with a loosely tied Figure 8, I can tie a Karash Single Loop on that Figure 8, but I can't tie other knots I know to be Bowlines.

Again, if you include the Karash Double Loop (or Single Loop) in the Bowline Family, then you must include an infinite number of other loops based on the Figure 9, Figure 10, Figurre 11, etc., as I explained in my previous post.


Karash Single Loop, Front


Karash Single Loop, Back
« Last Edit: July 16, 2011, 03:08:58 AM by knot4u »

agent_smith

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #23 on: July 16, 2011, 03:51:02 AM »
Quote from knot4u:  Posted on: July 13, 2011, 07:36:18 PM
Quote
Try these tasks:

Task A
1.  Tie an Overhand Knot on a bight.
2.  Without completely untying that Overhand Knot on a bight, can you tie a Karash Double Loop on that Overhand?
NO.


Actually, YES! You can.

Lets be 100% clear here. I am NOT stating that the Karash double loop is a Bowline! What I am stating is that your hypothesis does not hold up (at least with regard to your 'task A').

This thread is about defining a Bowline. I am seeking a robust definition - a workable theory. I think others would like to see such a theory also. I deliberately chose ABoK #1080 as a comparison to the Karash double loop because of the similar form. I thought this would be a great test of the theory. As I stated, you can tie a Karash double loop starting from ABoK #1009 (without untying #1009). I admit that you need to induce a half rotation to #1009 (sort of like a munter in form) before performing the #1080 backflip maneuver. But, you do not need to untie #1009!

I liked DerekSmith's hypothesis...that is until he did his own backflip ! DerekSmith's hypothesis was based on a particular form and structure which he was able to indicate clearly with the use of color.

knot4u, your hypothesis is based around #515 and #1009, in that, you must be able to tie a Bowline from one of these knots as a starting base. I think thats what your hypothesis is. Is this correct?

I am still hoping to hear more from DerekSmith in terms of argument/further theory on why he believes the Karash is a Bowline variant...perhaps with more coloration!

I am merely stating facts here...nothing more, nothing less.

Mark
« Last Edit: July 16, 2011, 03:53:08 AM by agent_smith »

DDK

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #24 on: July 16, 2011, 06:35:02 AM »
. . . As shown in the video, you tie the Karash Double Loop by starting with a loosely tied Figure 8 on a bight.   . . . Figure 10 (Stevedore) on a bight.  . . . (Figure 11, Figure 12, etc.), then the number of knots you must now include in the Bowline family is theoretically infinite.

That's absurd.  Let's not be absurd.

I believe knot4u has a legitimate point.  If the nipping structure is left out of the definition of a bowline, there is much that one could call a bowline.  This irreverently mocks the fact that the very simple bowline (ABOK 1010) is a relatively good start to a secure fixed loop.  As an example, the Karash SINGLE Loop is a lousy start to a secure fixed loop as it easily slips.  Those single loops that do not slip easily are, from what I've seen, more complex than the simple bowline.

DDK

Dan_Lehman

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #25 on: July 16, 2011, 03:27:47 PM »
Quote from knot4u:  Posted on: July 13, 2011, 07:36:18 PM
Quote
Try these tasks:

Task A
1.  Tie an Overhand Knot on a bight.
2.  Without completely untying that Overhand Knot on a bight, can you tie a Karash Double Loop on that Overhand?
NO.


Actually, YES! You can.
...What I am stating is that your hypothesis does not hold up
 (at least with regard to your 'task A').

While not buying into Knot4U's criteria,
I do believe his assertion in "task A",
so I'll need to see what it is you think disproves that.
the direction of certain parts is opposite between
the two cited starting knots, and I see no way
around that to achieve the same result.

--dl*
====

Dan_Lehman

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #26 on: July 17, 2011, 03:12:22 AM »
  I believe that it is a self-evident truth, that has no need for any other justification :
   If part of a knot is a bowlne, the whole knot remains a bowline - albeit a more complex one.
   As part of the Karash loop is a bowline indeed, ...

???  What is this part that is a bowline, please?


BTW, the single-strand structure corresponding to the so-called
"Karash double loop" is given in "Hensel & Gretel's" EKFR
as the "twist bowline" --for whatever that's worth (one might
surmise that they invented the name, if not the knot as well).

--dl*
====

Dan_Lehman

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #27 on: July 17, 2011, 03:20:45 AM »
As an example, the Karash SINGLE Loop is a lousy start to a secure fixed loop
as it easily slips.

???  In what material & force(s) are you finding slippage?
I've tried a couple of materials and used a pulley, but see
no hint of slippage.  (Btw, Mr. Karash had the twin-eye
knot tested to rupture, and it performed well, in some
low-elongation kernmantle (11mm or thereabouts) rope,
IIRC.)

--dl*
====

Dan_Lehman

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #28 on: July 17, 2011, 03:29:34 AM »
How do the debaters here classify Ashley's #1033,
the carrick loop --which begins exactly as #1010
through the turn around the SPart with the tail,
but then takes the tail (instead of immediately passing
back out through the nipping loop) over the SPart-side
eye leg and then out through the central nipping loop
but in the same direction (vis-a-vis loop's *side*)
as it entered (i.e., so that it could now trace the
first pass of the tail for a 2nd course).

--dl*
====
« Last Edit: July 18, 2011, 06:12:26 AM by Dan_Lehman »

alpineer

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Re: What defines a Bowline? - structure, characteristics, topology
« Reply #29 on: July 17, 2011, 05:58:52 AM »
As an example, the Karash SINGLE Loop is a lousy start to a secure fixed loop as it easily slips.   

In slick braided poly I've found the Cowboy Karash Single doesn't slip(under manual tension), however the Regular Karash single will. If the cowboy version doesn't slip under higher loading I would have to say that I am very impressed with this knot.  In nylon cordage my guess is the Karash Double does a good job of isolating each eyeloop from the other by very simple locking mechanism.  Even as a Cowboy Sheet Bend type of knot it seems to be a very secure knot.  In cyclic loading any slack in the collar is taken up by the loaded leg and not the tail. For the record I don't consider the Karash to be a Bowline. It doesn't have Derek's cited SB Core form. In the Knotting world "function follows form".

alpineer
« Last Edit: August 24, 2013, 11:15:19 AM by alpineer »