International Guild of Knot Tyers Forum

General => Chit Chat => Topic started by: alpineer on March 20, 2013, 11:04:10 PM

Title: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 20, 2013, 11:04:10 PM
   Some months ago I became intrigued by a special Bowline variant comprising a "double-loop" nipping structure which forms a single tresse - or braid - around the knot's Bight. The structure could also be described as an open i.e. torsionless Elbow, referring to it's two-dimensional likeness to the proper Elbow, and where open means "containing no overall line torsion" (proper Elbow = 720 deg.). The tressed Nip is the key to this Bowline's working attributes and is why I prefer to call it the Tresse Bowline. If prior documentation exists (under another name?) for the Tresse Bowline I've not been able to locate it.

   Tying the Tresse Bowline is easy. One method involves making an Underhand loop and laying an Overhand loop on top of it. Treat the paired loops as a single loop and continue tying as you would for ABoK #1010. The knot's nipping structure should be dressed in it's signature elbow-like tressed form for easy identification. This last step is not critical to the function of the knot, but serves to confirm that it has been tied correctly.

   The Tresse Bowline was tied in a variety of materials and natures thereof.* Informal tests - some involving forces of up to 350 lbs. - were conducted and in all cases the knot performed admirably while demonstrating an ability to maintain a good balance of the most desirable knot attributes. The tests (which included shaking, whipping, flipping, flopping, and dropping) indicated that the Tresse Bowline is:
Stable
Secure
Not prone to jamming
Not prone to ring-loaded failure
Easy to untie after heavy loading

   With respect to some simple static load testing, the Tresse Bowline was indicated to be weaker than Bowline #1010. By how much? I can't say. Knot efficiency tends to be the least important of desirable knot attributes due to the high unknotted breaking strength of modern lines.

   IMO more [rigorous] testing is warranted for the Tresse Bowline. Of particular interest to me is how the knot would perform in HMPE Spectra/Dyneema. Any takers?

   It's doubtful that a particular Bowline will ever be discovered that would achieve "Holy Grail" status, but I would argue that the Tresse Bowline can come closest to the ideal "Bowline for all Reasons", more than any other.

   

*Tests were conducted using 3mm(?) nylon cord, 6-7mm accessory cord, 10.5mm dynamic kernmantle rope, slick braided PP, stiff laid PP, 4mm shock cord, and other unspecified cordage of small diameter.



WARNING!  It should go without saying, but nevertheless it cannot be overstated, that any knot which might be considered for applications where life is on the line must undergo rigorous testing procedures in a safe, secure and controlled environment by experts or professionals qualified individuals in order to prove it's worthiness for such applications. I accept no responsibility for any injury, or death, caused to any person(s) resulting either directly or indirectly from the use of (in any situation) the Tresse Bowline. USE THIS KNOT AT YOUR OWN RISK.

Brett McConochie
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: SS369 on March 21, 2013, 01:25:42 AM
Hi Alpineer.

I gave your construct a whirl using some Titan (BlueWater) 5.5mm Dyneema and as well I used 1/4 inch solid braid nylon.

I like the compactness of this bowline and it lives up to your claims, almost.

The knot was dressed as tightly as my hands could do, using all the parts individually till I had the affair as snug as possible.

What I find is that the during the ring loading, the parts migrate to the point of the collar almost being drawn into the the upper nip using hand strength and body weight, so I can only imagine what serious loading (both slow or sudden) would do.

The biggest drawback, to me, is that after loading it to 300 lbs and then bouncing using body weight, I had to use round nose pliers and a spike to untie it.

I believe that the double nipping coils act very much like double overhand or perhaps a constrictor. No doubt very secure!

Based on my quick unscientific tests I would say it would be a satisfactory tie in loop, except for the untie-ability factor. In my opinion.

Thank you for sharing this.

SS
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 21, 2013, 10:02:48 AM
Hello SS369,

Thanks for giving the knot a test and I hope you will continue to experiment with it further. Were your findings the same for both the Dyneema and the nylon?

In the context of knot testing, ring-loading* refers to the end result of such an event causing the capsizing or catastrophic failure of a knot, and generally not expected or intended to be part of a normal working scenario, but rather serving as a means for assessing a knot's ability to maintain it's effective working form in the event that it does suffer a ring-loading event. Still, were you not able to pull the Standing Part and the Tail simultaneously and thereby gain some of the collar back? Flipping the collar back is the key to breaking the knot's grip, as you know. If you can roll the outer part of the upper nip down and away from the collar you will gain more range for flipping the collar back. Still again, it's not necessary nor advisable to draw the collar up so close to the nip. The collar will not draw up when loaded and will remain easy to untie. Did you intentionally push the nip towards the collar before testing? Your photo shows a perfectly tied Tresse Bowline. Or is there something peculiar to Dyneema's nature that causes the collar to move towards the nip as load is applied in the usually intended manner? Sorry for the questions.

alpineer     


*Ring-loading as an event refers to a knot's Eye being loaded from within it's boundaries as if it were a sling. 
     
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Sweeney on March 21, 2013, 12:42:34 PM
HI Alpineer

Yesterday I tied a mirrored bowline (using a girth hitch as a base) in some 1.1 mm monofilament nylon (strimmer line in the UK). This stuff is very stiff and springy and a real PTA to tie a knot in - most just spring apart so this was to see how well a mirrored bowline held together.

Anyway the mirrored bowline seemed unchanged today so I tied your Tresse Bowline in the other end of the same piece of mono and pulled until the line broke. The break came at the Tresse Bowline, the mirrored bowline was unchanged visually but importantly neither showed any sign of slippage. As this material is prone to slip fairly easily it does point to the Tresse Bowline being very secure and as you say in modern rope breaking strength is rarely an issue.

This was hardly a scientific test but it was interesting that once set both of  the bowlines showed admirable resistance to springing loose as well as having high security - life's too short to start undoing knots in this material  though.

Barry
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: SS369 on March 21, 2013, 01:35:53 PM
Hello SS369,

Thanks for giving the knot a test and I hope you will continue to experiment with it further. Were your findings the same for both the Dyneema and the nylon?

In the context of knot testing, ring-loading* refers to the end result of such an event causing the capsizing or catastrophic failure of a knot, and generally not expected or intended to be part of a normal working scenario, but rather serving as a means for assessing a knot's ability to maintain it's effective working form in the event that it does suffer a ring-loading event. Still, were you not able to pull the Standing Part and the Tail simultaneously and thereby gain some of the collar back? Flipping the collar back is the key to breaking the knot's grip, as you know. If you can roll the outer part of the upper nip down and away from the collar you will gain more range for flipping back the collar. Still again, it's not necessary nor advisable to draw the collar up so close to the nip. The collar will not draw up when loaded and will remain easy to untie. Did you intentionally push the nip towards the collar before testing? Your photo shows a perfectly tied Tresse Bowline. Or is there something peculiar to Dyneema's nature that causes the collar to move towards the nip as load is applied in the usually intended manner? Sorry for the questions.

alpineer     


*Ring-loading as an event refers to a knot's Eye being loaded from within it's boundaries as if it were a sling. 
   

Hi Alpineer.

I try to tie all the member's offerings and wanted to give yours a good effort too. It looked deserving!

I did find the same effects in both the Nylon and Dyneema, the Dyneema being the more difficult. It is a truly stout cordage. If you get it tight it stays tight like an anaconda snake!

As I wrote I dressed the knot as snugly as I do all knots at "test" time. It's my standard.
Yes, I could have left the collar part as you say (loose), but then that would be outside my norm.
I will try it using both to verify what you've said. I suspect it will be easier to untie, but then it won't be loaded nearly as much or even near the working limits of the material.
I tentatively suspect that it would deform and the tail would feed into it till it was consumed (Dyneema).

Ring loading is a concern for climbers, though not necessarily for the climber himself (actually yes ultimately), but for the belayer who is supposed to be anchored. And if the loop was to be used in some other form of anchoring scenario as well. Things do have a drift towards Murphy-ism unfortunately.

If my photo had been of better quality you would see that my snugging had indeed bent the standing part fairly hard by the collar. This is where I suspect a break to occur if the load was hard and sudden.

Barry: Is this where your break occurred?

I am certainly not writing it off. I'm hoping to help find its limitations, pros/cons with you.

I've recently acquired some 10.5mm ProTac static (now used once!) that I'll drag out and give it a go with and see what happens.

SS
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Sweeney on March 21, 2013, 04:08:31 PM

If my photo had been of better quality you would see that my snugging had indeed bent the standing part fairly hard by the collar. This is where I suspect a break to occur if the load was hard and sudden.

Barry: Is this where your break occurred?


Scott

As far as I can tell from the pieces left it probably did, the break happened too quickly to be able to see it coming. This might have been a contender as a fishing knot but for the reduction in breaking strength which would not be acceptable. Could be useful as a permanent mooring loop though rather than a splice especially in kernmantel. It would not be so likely to loosen under repeated loading/slackening as the standard bowline (ABOK 1010) and is small and neat once dressed.

Barry
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 21, 2013, 05:13:33 PM
As I wrote I dressed the knot as snugly as I do all knots at "test" time. It's my standard.
Yes, I could have left the collar part as you say (loose), but then that would be outside my norm.
I will try it using both to verify what you've said. I suspect it will be easier to untie, but then it won't be loaded nearly as much or even near the working limits of the material.
I tentatively suspect that it would deform and the tail would feed into it till it was consumed (Dyneema).

I've recently acquired some 10.5mm ProTac static (now used once!) that I'll drag out and give it a go with and see what happens.

SS

I'm looking forward to the results of your testing. So far, your tests (as well as mine) have indicated that ring-loading the T. Bowline does not cause catastrophic knot failure. 

HI Alpineer

Yesterday I tied a mirrored bowline (using a girth hitch as a base) in some 1.1 mm monofilament nylon (strimmer line in the UK). This stuff is very stiff and springy and a real PTA to tie a knot in - most just spring apart so this was to see how well a mirrored bowline held together.

Anyway the mirrored bowline seemed unchanged today so I tied your Tresse Bowline in the other end of the same piece of mono and pulled until the line broke. The break came at the Tresse Bowline, the mirrored bowline was unchanged visually but importantly neither showed any sign of slippage. As this material is prone to slip fairly easily it does point to the Tresse Bowline being very secure and as you say in modern rope breaking strength is rarely an issue.

This was hardly a scientific test but it was interesting that once set both of  the bowlines showed admirable resistance to springing loose as well as having high security - life's too short to start undoing knots in this material  though.

Barry

Hi Barry. Thanks for giving the Tresse Bowline a go. 

   
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Dan_Lehman on March 21, 2013, 07:01:24 PM
The structure could also be described as an open i.e. torsionless Elbow,
referring to it's two-dimensional likeness to the proper Elbow, ...
/ /
The knot's nipping structure should be dressed in it's signature elbow-like
tressed form for easy identification.  This last step is not critical to the function
of the knot
, but serves to confirm that it has been tied correctly.
I'm having trouble with this "Elbow" [capitalized!] structure :
should it be familiar to us?  --else, any references to cite?

As for "not critical ...", there should be something definite
said here about dressing --not an either/or/anything-goes
indication, as this seems to be.  (E.g., one could ask for one
form --for checking correct crossings--, and then specify that
this more open form be set into something more compact.
And, yes, it might be that the entanglement tolerates open
or compact dressings --which could be helpful if working with
such stiff rope that compactness was not easily achievable
(thinking of some ornery BW II old rope I have beside me!).)


Quote
The Tresse Bowline was tied in a variety of materials and natures thereof.*
Informal tests --some involving forces of up to 350 lbs.-- were conducted
and in all cases the knot performed admirably while demonstrating an ability
to maintain a good balance of the most desirable knot attributes.  The tests
(which included shaking, whipping, flipping, flopping, and dropping) ...
/ /
With respect to some simple static load testing,
the Tresse Bowline was indicated to be weaker than Bowline #1010.
And among these tests was one (or more) that entailed breaking
the knot, such that your assertion of strength compared with the
(common / #1010) bowline has a basis?  --surprising my guess.
What material was used, and how many tests (for strength)?
(And did you set the knot so (overly) snug as SS369 shows?!)


Quote
indicated that the Tresse Bowline is:
Stable
Secure
Not prone to jamming
Not prone to ring-loaded failure
Easy to untie after heavy loading

But missing from this set of qualities is the one most important
to rockclimbers (& other life-critical uses) : slack security
(unless "security" is to mean this --but then it should be noted,
as security-under-strain is the usual sense (and has become
more relevant with some modern fibres!)).

Quote
Knot efficiency tends to be the least important of desirable knot attributes
due to the high unknotted breaking strength of modern lines.

It's unfortunate that "efficiency" has been introduced into
the knotting literature as a synonym for "strength" : it should
serve more generally, not only indicating how much of tensile
strength is *consumed* in the knot, but how much material
is used, and maybe how much time --as for some applications,
this might be critical.

As for "strength of modern lines", I don't buy this : one hopes
to preserve whatever strength one has, usually --you don't
replace 3/8" double-braid polyester with 3/8" HMPE and take
consolation that the lines have roughly equal knotted strength;
no, you hope to replace the thicker & much heavier (and stretchier)
line with much lighter & thinner (sometimes thinness is a problem,
though!) but possibly more costly line which suffers no greater
loss of termination (knotting or, as we know, splicing) strength
efficiency.

Quote
Of particular interest to me is how the knot would perform in HMPE Spectra/Dyneema.
Any takers?
For starters, there is the doubt that knotting such material
is at all worthwhile in terms of strength --all testing of it
so far has cast doubt as to knots being anywhere reasonably
strong as we would expect, from historical materials.
Of particular interest should be this video of Brion Toss's test
of not-quite-my-recommended "mirrored bowline" --he omitted
the reflected collar, alas--:
www.youtube.com/watch?v=Fy6Y2Xoo4Ak (http://www.youtube.com/watch?v=Fy6Y2Xoo4Ak)  [ in 5/32" HMPE 12-strand ]
.:. the eye knot holds, but breaks at what Toss guesses
is not-so-high load --the device wasn't calibrated(?!).

Quote
It's doubtful that a particular Bowline will ever be discovered
that would achieve "Holy Grail" status, but I would argue that
the Tresse Bowline can come closest to the ideal
"Bowline for all Reasons", more than any other.
Firstly, one could ask why one puts "bowline" into this
quest for a Holy Grail --why not simply leave it open to
whatever meets the presumed requirments.  Then, one
can question that any set of requirements can be agreed
upon as constituting Holy Grail!  --more likely, it will be
shown that different applications simply don't need
some such included qualities, but they might not be in
conflict with ones that they do need.

But I'll question how you see this variant as superior to the
mirrored bowline, which to my mind has demonstrably
better security when slack (and is easier to tie in that BW II !)?

Somewhat similar to what the OP shows was discussed
some years ago as a follow-on version to the OP's knots
presented here
http://igkt.net/sm/index.php?topic=1080.0#msg7298 (http://igkt.net/sm/index.php?topic=1080.0#msg7298)
&
http://hilarynelson.com/Hobbies/Knots (http://hilarynelson.com/Hobbies/Knots)
--the "improved" knot, i.e..

I'd tend to give this (as is noted) an additional binding
wrap; there might be some tweaking in the dressing
stage to enhance strength, but that's pointing towards
a dubious quality if indeed such care is needed; it otherwise
seems to have blood-knot features, and maybe the tight
turn of the SPart doesn't play so important a role in strength
as one might fear --that the tightening coil of wraps around
this will help.  (untested, to my awareness)


Quote
WARNING!  It should go without saying, but nevertheless it cannot be overstated,
--from none to all !!   ::)

Quote
... that any knot which might be considered for applications where life
is on the line must undergo rigorous testing procedures in a safe, secure,
and controlled environment by experts or professionals in order to prove
it's worthiness for such applications.

"professionals or experts" : I might prefer just the latter,
however they might fit the former.   ;)
But can you truly say that this is the case for state-of-the-practice
knots?  E.g., we heard not so long ago from a British caver about
the use of the bowline on a bight with regard to some French testing
that showed it to have a vulnerability to spill, in a special case.

.:.  It would behoove some group of experts to build a check list
of testing that could be regarded as rigorous.  I think that in most
cases one will find that testing amounts to some form of strength
testing --be it static or dynamic loading--; and that says not much
regarding slack-security, and other qualities; and even regarding
strength, the testing might be less than rigorous.  (E.g., the slow-pull
loading of a test device doesn't well model the holding-a-mass loading
one would have, say, in abseiling --where, if the offset water knot
"rolls", it gets a sort of "shock" loading, not a delay while the device
regains tension !)


--dl*
====
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Dan_Lehman on March 21, 2013, 07:34:21 PM
The knot was dressed as tightly as my hands could do,
using all the parts individually till I had the affair as snug as possible.
/ /
The biggest drawback, to me, is that after loading it to 300 lbs and then bouncing
using body weight, I had to use round nose pliers and a spike to untie it.

Which begs the question Why set the knot so tightly, of the collar?!
IMO, if you cannot untie any "X"-bowline --i.e., one with a "proper"
collar--, you've gone wrong in its setting --the collar being the
key to easy untying.  (Now, in some cases of heavy loading,
there could be some slippage in material whose diameter
has been reduced in tension such that upon the removal
of force the knot's strands *swelled* and left the collar
unusually tight around the returned-diameter SPart!)

"300 pounds" suggests a 2:1 pulley and body weight
--is that so?  --and a good pulley (I count my 5:1 as
rather poor, so need the bouncing to convince me that
I've at least surged towards its theoretical force (and
then realize that the crummy friction should hold it at
that extension/tension))?
It's certainly a force able to show effects that might
surprise one vs. manual loading, and make one take
care before testing some knot --if untying is desired,
without tedious use of tools (and even then)!

Quote
I believe that the double nipping coils
... aren't so well described as that, given the actual
geometry of the knot : that it's a helical part more
than some definitely circular turn, doubled.

Alpineer asks:
Quote
Were your findings the same for both the Dyneema and the nylon?

This surprises me : there was no "Dyneema" here, in any effective
presence for this sort of testing --i.e., it was core material, not
contributing the slickness of fibre to points of contact that
would show effect in mere stress testing.  (The stiffness of
the cord is another matter.)  Conceivably, the core can slip
within the mantle so that there is effect --and effect not
often suspected / recognized-- in full break testing, or maybe
in some repeated usage where the slippage accumulates,
but that requires such testing to reveal it.  (There have been
reports of a polyester/nylon sheath breaking and the hi-mod
core pulling out, e.g. ; or images where the core remains
intact at a broken sheath.)

The Brion Toss video I URLinked to previously (above) shows
bare HMPE 12-strand cord being tested.  He has one also
showing a dbl. bowline just slipping out through the nub,
collapsing the eye --a marvel to behold!


--dl*
====
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Dan_Lehman on March 21, 2013, 07:42:50 PM
A bowline similar to the OP's, which can be seen as but
a re-dressing of the double bowline into a helical geometry,
is presented here.  I had it tested some ages ago, and it seemed
to perform okay, though sub-sensational (to my hopes :P ).

The design goal was to have the SPart make a gradual curve
into the knot before making its U-turn.  Insofar as I can deduce
where the break came (nb: no unreasonably tight collar),
it was somewhere along this turn, and in the strand (1 of
3 of the 1/4" nylon rope, i.e.) on the inside of the curve.

[OO  :o OOPS, as one could SEE --if one were paying attention!--,
the break in this knot was in two of the three strands,
whose best-guessed positions were more inside than
outside of the curve, vis-a-vis the unbroken one.
It is interesting to note that the very similarly curved SPart
of the knot (my "#56" shown in my next msg.) broke only
1 strand but had the same strength; one might have thought
that if the forces could be so evenly apportioned to break two,
it would almost necessarily be at a greater force!  (Perhaps
there are other factors at work to explain these results.)]

Here are 3 views, including a sketch.  Figured break strength
was 71% or 68%, depending upon whether the eye splice's
strength was used as 100% or the commonly given 95%
as the basis of tensile.  (Note that I tied the eye knots on
either end of the specimen in opposite handedness --I don't
think that was my intention, alas.)


--dl*
====

postscript : The rope in the photos is held by either a
railroad spike --handy to hammer, pry (maybe screw),
and sometimes tear (this one having a sharp point)--
and some old big link of a chain or other device, well
worn/grooved and *aged* (and appropriately sized
to be a frame to the knotted rope here).
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on March 21, 2013, 08:08:34 PM
   I am glad you have discovered this very tight, efficient double "nipping structure", that I have called " double, crossed coils nipping loop ". Its great advantage is that it is very table, almost self-stabilizing, even without the presence of any "collar structure" ! However, I believe that this advantage manifests itself mainly in the case of the "Eskimo" variation, where the whole nub lies perpendicular to the axis of loading, not parallel to it. ( See the first attached picture ). I have tied the most simple bowline-like (post-eye-tiable) "Eskimo" (-)bowline that uses this structure, and I have seen that, indeed, it is a very stable and secure knot ( See the third and fourth attached pictures). When the knot s nub lie parallel to the axis of loading, as in the knot you show, the two legs of the collar do not have any "handle" or "step"  that can provide additional support for the standing end s and returning eye leg s grip on them. So, in contrast to the "Eskimo" variation, I feel that a large portion of the constricting power of this nipping structure is "wasted" in constricting itself, and it is not exploited by those straight legs of the collar.
   Moreover, when one decides to tie such a double nipping structure, it is almost irresistible to proceed just half a step further, and tie the most well-balanced, self-stabilizing, tight and secure Constrictor bowline ( shown at the fourth attached picture). At the end of the day, a more balanced knot is, most of the time, a more symmetric knot, and a more good-looking knot, too. That is my main objection to this bowline : It is something less, functionally and aesthetically,  than the Constrictor bowline - without any reason  ;).
   Another objection I have with this kind of bowlines, is that, although their double nipping loop structure is fine, their collar structure remains simple - which is fine in the case if the simple nipping loop of the common bowline, but not when one has decided to go to a next level. Also, one can not just "add" a second collar structure to get a double nipping loop / double collar eyeknot, a condition that I believe is sine qua non for something that could replace the retraced fig.8 knot. The "Pretzel" nipping structures, for example, the simple and the twisted forms of it, are even more balanced and self-stabilizing than the shape "8" nipping structure of the knot you show - but my attempts to add a second collar on the corresponding eyeknots have not produced any good-looking knot.
   Having said that, I believe that this is a fine, secure crossing knot bowline, easy to remember and to tie, that is worth of a further study.   
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Dan_Lehman on March 21, 2013, 08:12:05 PM
With the same design goal as above,
I also discovered a knot in which the SPart
simply *helixes* its way through the nub,
as does e.g. the Bimini twist --but this
lacks the reassuring feature of the above-shown
"my#97" bowline of a U-turn : i.e., one can
fear that the tail's knotting around the helix
might slip, under high loading (and that one
must in any case somehow anticipate the
material's transformation under load to get
just the right degree of curvature ...
(to *win* the knot-strength prize!)).

At least I was consistent in handedness, here.

The 2nd photo tries to give a close-up of the presumed
break point --the best guess point where one can run
back the fibres to where they must've been at rupture
(those on the SPart side got sprung way out into the
rope!).

NB: in the several knots tested in this quarter-inch,
moderately soft-laid nylon (hardware-store variety) rope,
most broke one strand and the testing was arrested upon
this felt loss of tension; a few broke two strands, and
these were strong.  #97 & "Hunter's X" & an end-2-end
knot with a blood-knot-like sharp u-turn (the break
being in the so-tightly nipped SPart by this turn, not in
the turn itself!); the like-#97's-helical knot here broke
just one strand (with equal force), and the eye splice
did so, as well; SmitHunter's broke just 1 but was only
3 %-pt.s weaker than the "X" version (given but ONE
test of each!).


--dl*
====
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Dan_Lehman on March 21, 2013, 08:31:19 PM
It's doubtful that a particular Bowline will ever be discovered that would achieve
"Holy Grail" status, but I would argue that the Tresse Bowline can come closest
to the ideal "Bowline for all Reasons", more than any other.


 :)   I'm remiss in not asking : do "all Reasons" go beyond practical ?!!

--for this thread to be in (mere) Chit Chat and not Practical forum!
(--or Explorations..., New...)


 ;)

Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on March 21, 2013, 08:34:35 PM
I also discovered a knot in which the SPart simply *helixes* its way through the nub,

  I wonder how you have not discovered the many helical knots that I have shown in this Forum ( shown, with pictures, not just talked about, with words...) -, in threads that you had participated, but had not said a word about them. Anyway, I am glad/happy we see some pictures, at last. Go on !
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on March 21, 2013, 08:57:47 PM
   One can tie those "Helical loops" using a simple S-shaped, a fig.8 knot, a double overhand knot / Strangle knot shaped, or even a fig.9 knot shaped "collar structure". In fact, any stopper can serve as a double-end core, within and around which the helical "open" nipping coil would be wrapped. Even if this collar structure is not a tightly woven knot by itself, the nipping structure, as a belt around it, can force it function as such - and keep its two openings at a close distance to each other.  See the attached pictures for some of the knots that have been shown in this Forum - without been "discovered" by anybody... :)
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: SS369 on March 22, 2013, 12:51:04 AM
The knot was dressed as tightly as my hands could do,
using all the parts individually till I had the affair as snug as possible.
/ /
The biggest drawback, to me, is that after loading it to 300 lbs and then bouncing
using body weight, I had to use round nose pliers and a spike to untie it.

Which begs the question Why set the knot so tightly, of the collar?!
IMO, if you cannot untie any "X"-bowline --i.e., one with a "proper"
collar--, you've gone wrong in its setting --the collar being the
key to easy untying.  (Now, in some cases of heavy loading,
there could be some slippage in material whose diameter
has been reduced in tension such that upon the removal
of force the knot's strands *swelled* and left the collar
unusually tight around the returned-diameter SPart!)

"300 pounds" suggests a 2:1 pulley and body weight
--is that so?  --and a good pulley (I count my 5:1 as
rather poor, so need the bouncing to convince me that
I've at least surged towards its theoretical force (and
then realize that the crummy friction should hold it at
that extension/tension))?
It's certainly a force able to show effects that might
surprise one vs. manual loading, and make one take
care before testing some knot --if untying is desired,
without tedious use of tools (and even then)!

Quote
I believe that the double nipping coils
... aren't so well described as that, given the actual
geometry of the knot : that it's a helical part more
than some definitely circular turn, doubled.

Alpineer asks:
Quote
Were your findings the same for both the Dyneema and the nylon?

This surprises me : there was no "Dyneema" here, in any effective
presence for this sort of testing --i.e., it was core material, not
contributing the slickness of fibre to points of contact that
would show effect in mere stress testing.  (The stiffness of
the cord is another matter.)  Conceivably, the core can slip
within the mantle so that there is effect --and effect not
often suspected / recognized-- in full break testing, or maybe
in some repeated usage where the slippage accumulates,
but that requires such testing to reveal it.  (There have been
reports of a polyester/nylon sheath breaking and the hi-mod
core pulling out, e.g. ; or images where the core remains
intact at a broken sheath.)

The Brion Toss video I URLinked to previously (above) shows
bare HMPE 12-strand cord being tested.  He has one also
showing a dbl. bowline just slipping out through the nub,
collapsing the eye --a marvel to behold!


--dl*
====

Wow! A whole lot of responses!

I set my knots snug because that is what I believe I should do for all good reasons.
It is a standard that I use when I investigate a knot of any kind. From that base I can  determine things for myself. After that baseline/benchmark other forms can be looked at.

I don't personally feel that my snugging all parts of the knot equals over tightening them. One fall can exceed my hand strength easily in tightening a knot.

As for my load test method that you inquire about Dan. I have a three hundred pound weight that I mount to my "test" knot by means of a shackle (in the case of a loop) or other non-detrimental means in the case of other types. With the weight suspended I some times climb on the weight and bounce my 180 lbs.
This gives me an understanding to some degree of what the knot is going to perform like.
No pulleys are used so it's pretty much one to one.

I climb and abseil quite often and I take some testing to the crags, though generally I have backup as warranted.

And yes there was Dyneema (core material) present and included in my simple test. No, not to destruction as my pockets are not quite so deep. I do believe that a sheath can influence things and of course we count on them to do just that. Hopefully positively.
And hopefully someone with some naked material will jump in here and give it a go.

SS
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: SS369 on March 22, 2013, 01:08:10 AM
Back to the OP.

Hi Alpineer, I tied your offering in two more ropes. The ProTac 10.5mm static and 10.6mm Dynagym (both BlueWater).

I did the same test procedure that I do across the board, regardless if some might think it superfluous or wrong or excessive.

What I found is the ProTac liked conforming to this knot and the Dynagym did not. The latter's construction is very springy and I really had to work the knot into shape and it took more time than I care for. My opinion only.
Another thing I found, using this particular rope (Dynagym) is that if the knot is a even a bit loose the tail will pull easily out of the coils.

The way I did this was to dress and snug the knot (overly so)  :), and then worked it loose (not too) leaving everything dressed as you showed it. Then I pulled the leg opposite the tail and caused movement. I have found this to be a tendency of stiff, hard ropes. It effects many well known and cherished knots so.
Another good reason to "overly snug" knots.  ;)

Btw, both specimens untied relatively easy enough.

Attached are some pictures of the test media tangled your way.

SS

Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on March 22, 2013, 01:16:52 AM
  Wow ! There is a miracle happening in the Forum !  :) Tests, and pictures of tested knots ! I can only keep my fingers crossed this will become the mainstream from now on ! We have too many knots, and too few tests - its time to balance the sheets. Thanks, SS369.
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 22, 2013, 03:20:36 AM
Hi Dan,
Thanks for your responsesssssssss. It's going to take some time for me to respond to yours and others (in no particular order), even the ones I choose to respond to.
Cheers,
alpineer
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 22, 2013, 01:31:27 PM
   I am glad you have discovered this very tight, efficient double "nipping structure", that I have called " double, crossed coils nipping loop ". 

Hi X1,
   Look closer, please. This " double, crossed coils nipping loop " shown in your photo is not the same structure shown in my photos, the difference being the degree of torsion present in each. It's an important difference, at least in the context of the Bowline. Your photo shows the double loop nipping structure typically found in the Double Bowline re-formed into what I call a closed Elbow, containing 720 deg. of torsion. My photos show the double loop nipping structure I call an open Elbow, which contains no torsion. The essence of my claim is this, that the Open Elbow is the most efficient nipping structure (for the Bowline), exhibiting the highest level of the combined attributes of simplicity, security, stability, and untiability, and in the broadest range and nature of cordage. [edit]: add compactness to this mix


    Moreover, when one decides to tie such a double nipping structure, it is almost irresistible to proceed just half a step further,   

I find no irresistibility in myself to do such. I want simplicity, married with the other attributes I've listed above.

Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on March 22, 2013, 07:18:31 PM
   Look closer, please. This " double, crossed coils nipping loop " shown in your photo is not the same structure shown in my photos, the difference being the degree of torsion present in each.

   I do not look the knots, I tie them and try to feel the forces that run through their body, as if it was mine s !  :) This is an "intrinsic" "view", which can tell us things that are not shown in pictures. Imagine you are a snake, and you are knotted and pulled by your head and tail - what do you feel ?
   The geometry of structure is the same, obviously, but you are right, this is never the whole story - not even the most important part of it. I can feel that the torsion in the structure you show in much less than in what I show, indeed. However, I believe that this is another advantage of the later in relation to the former !  :) This torsion is beneficial to the gripping power of the two wraps, because it works as an invisible "skeleton", it stabilizes the form of the "coil tube", and it will not allow it to lose its initial symmetry when it will be loaded in this eccentric way it is to be loaded. Torsion is a very effective force, and that is why the torsion springs were used in tanks and the VW beetle !  :) It is a good thing, if we can use it to our behalf. I know that there is a common misunderstanding, that torsion "absorbs", in some way, the tensile forces, so what is added in torsion should be subtracted from tension. This is not correct. You can have torsion forces alongside tensile forces- a rope or a rod can be "twisted" AND pulled/pushed, at the same time, without the amount of the twist absorb, and diminish, the amount of pull/push.
   So, the test I propose to you is not visual, it is corporeal !  :) Tie the two structures with a lose collar, and "see" / "feel" what holds better.
   The twisted / torsioned rope segments of the wraps of the knot I show will be constricting the encircled body of yours, like the turns of another snake ! The head and the tail of this snake will almost cut you in two, with this scissors-like action - the one pulling towards the standing end, the other towards the tip of the bight.
   I had tried the "common" application of this crossed coils double nipping loop many times, before I had discovered the "Eskimo" version...I agree that the visual simplicity of the "common" version is very attractive, while the "Eskimo" version looks like a ...whatever. However, I was amazed by the constricting power of the "Eskimo" version - which also utilizes the L-shaped continuation of the standing part and the returning eye leg, the "handle" and the "step" which facilitate the job of the nipping structure - and that is why I had preferred it. I can assure you that I have a soft point in the simplicity of the knot structure, and I would nt hesitate to sacrifice a reasonable portion of gripping power, to retain it. However, here we have a GREAT difference ! The one structure can work even without the collar, as an adjustable loop, while the other is only stabilized by the collar - moreover, the nipping structure is much more complex than the collar structure, which remains rudimental ... This discrepancy between the amount the ante-eye and the post-eye knotted structures is something that bothers me, and I always try to tie bowlines where the rope segment will be almost as much convoluted in the nipping part as in the collar part. If I see a bowline where the one part is elaborated, and convoluted more than the corresponding part in the common bowline, while the other part is left unchanged, I sense that the design of this knot has not been finished yet !  :)

the Open Elbow is the most efficient nipping structure (for the Bowline), exhibiting the highest level of the combined attributes of simplicity, security, stability, and untiability, and in the broadest range and nature of cordage.

    I have tied many nipping structures, if not ALL of them, in a systematic way, I can assure you. However, I can not confirm what you say - and I very much doubt it. However, you can persuade me VERY easily : Tie all the structures I propose, test them, and report your results !  :) Your very high-flying tone about the "Open Elbow Structure" will lower a little bid, but, in the mean time, we will have learned many thing we still ignore .. :) Is this structure more simple than the Water bowline s or the Mirrored bowline s ? No, of course not, and I would nt even argue about it. Is it more secure ? We have to test them to tell. Is it more stable ? Here, my dear alpineer, I will resist my temptation to lough loudly. It is a most unstable structure, that has to rely in the collar structure s belt to remain in one piece! It imposes a great strain on the base of the legs of the collar - I almost "feel" the pain they feel ! My KnotGod, it is but a poor loop-sided fellow that needs the collar stick to walk ! Is it untiable ? Yes, it is - but have you tried to untie the Twisted Pretzel structure, for example, to see the difference ?  :) "Broader range and nature of cordage" are not of much concern... I tie and try the secure bowlines in climbing ropes, 9-12 mm, because those are the ropes that will be used, if any of those is going to be used as a replacement to the retraced fig.8 knot. I do not tie and try them on small, soft cordage, or on monofilament fishing line, for example, because I see no point of using a secure bowline in non-critical applications - the common or the "Eskimo" bowlines are just fine for them.

   I want simplicity, married with the properties I listed above.

   Simplicity is imperative to me, too.. But tell me, please, alpineer, do you really believe that the asymmetric 8 shaped structure you show, is really simpler than the Girth hitch of the Mirrored bowline, or the Constrictor of the Constrictor bowline ?  Have you tied MORE times this almost crippled 8 structure ( which is beautiful only in the eyes of a blind mother... :)), than a Cow hitch, or a Constrictor ? Simplicity is depending upon the amount of information of something, that is needed in order to store or retrieve it. May be the simple Clove hitch is simpler than the Constrictor, indeed - or the Water bowline than the Constrictor bowline. However, the "Open Elbow", or the "Pretzel", are not - they are more complex, and an indication of this fact is that they can be tied wrongly in more than one ways !
   Perhaps you have not noticed my argument about the difficulty of adding a second collar in this structure. Do you believe that such a modification would be redundant ?
   Now, it often happens that we come to see a cup that may look like it is made of pure gold - or that it IS made of pure gold, indeed. Is it the Holy Grail ? You can believe it - but the prudent thing is to not bet anything you have on this... :)
    I would also like an experimental comparison of this bowline to the "similar" Locktight bowlines tied by Dan Lehman - because I can not find why they would be very different. I prefer the U-turn of the eye leg around both legs of the collar as at the structure you show, that is true, but this might not be the whole story (1).

1. http://igkt.net/sm/index.php?topic=1234.msg8419#msg8419
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on March 22, 2013, 08:25:09 PM
   I have read my previous post, and I feel that it sounds too critical... :) So, I have to repeat that this bowline is a very simple, easy to remember and tie eyeknot, with a very tight double nipping structure, that deserves further, detailed examination and evaluation. I do not say it is no good ! - I only doubt that it is "the best", the Holy Grail ... because there might be no such thing, and because I have met a number of other tight double nipping structures, of about the same complexity, that are as secure and simple ( and perhaps even simpler) than this.
   One of my concern is that the nipping structure is much more elaborated / sophisticated / convoluted than the collar structure - which remains the old "proper" bowline s collar, in a knot that is meant to go beyond the common bowline... One possible way to do something about it, without spoiling the character and the simplicity of the knot, is shown at the attached picture. Another similar solution to the same problem is the slightly different "braided" collar structure, offered by the very clever and original "Braided bowline", by SS369 (1).

1. http://igkt.net/sm/index.php?topic=4283.msg26651#msg26651

P.S. The interested reader might notice that the shown bowline, as well as a number of other similar eyeknots, can be derived by a simple modification of the Sennit, the Symmetric Simple Sinon (SSS) and/ot the Vice Versa/Versa Vice/Reever bends. Usually, an untucking of a limb of the one side, which afterwards is forced to make a U-turn and be connected with a limb of the other side to form the eye, would be sufficient.
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on March 23, 2013, 12:09:41 AM
   So, if we wish to go one step further, we will ask ourselves : why does the second leg of the collar ( the tail ) has to follow the same, first leg s path ? In the "Eskimo" versions ( there are more than the one I have shown), it passes in between the first leg ( the continuation of the returning eye leg)  and the standing part. That is the place where it is squeezed harder, so it seems reasonable to try to replicate this situation in the "common" version as well.  See the bowline at the attached picture, which is a modification of the knot presented at the previous post. The interested reader would recognize the symmetric bend which lies at the core of this eyeknot - it was published in this Forum some time ago, and it is a modification of another member s similar but more complex knot.
   
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on March 23, 2013, 01:37:56 AM
double, crossed coils nipping loop ". Its great advantage is that it is very table, almost self-stabilizing, even without the presence of any "collar structure" ! However, I believe that this advantage manifests itself mainly in the case of the "Eskimo" variation, where the whole nub lies perpendicular to the axis of loading, not parallel to it.

  I understand that many people would not understand what I am talking about here ...so I have to show some pictures.  :)
  One does not see any collar in the double, crossed coils nipping structure shown in the attached picture, does he ?  However, the interested reader who does not only look at knots, but also ties them, would be surprized by the holding power of this structure, even in the absence of any collar, even when it is deformed  That is why I say that we should better place and manage to maintain the shaped "8" structure perpendicular to the axis of loading, not parallel to it - where it would not be stable any more, and would need the active presence of the collar to remain in one piece. If the collar, for whatever reason, gets loose, the "perpendicular" double crossed coils nipping loop would still hold, while the "parallel" double crossed coils nipping loop would open up, like a peeled banana !  :) In any crossing knot bowline, we mainly seek one, and one only thing : to keep the form of the nipping structure closed, without much aid by the collar, in any loading configuration. We can not suppose that the two eye legs will always be equally loaded, or even that they will be loaded at the same time ! The one leg can be caught up somewhere, and be forced to carry the whole load, while the other will get loose. A more self-stabilizing nipping structure would be able to maintain its integrity, remain closed, and hold during this phase, while a structure that is heavily depending upon a loaded leg, would be deformed and lose its gripping power altogether, if this leg happen to be loosened.
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 23, 2013, 07:11:07 PM
   On Thursday a friend and I set up a pull-testing station in his back yard between two stout mature trees and at near ground level. Sorry, no photos. I forgot my camera. A ratcheting cable winch puller (1000 lbs. first layer capacity) was used to apply the forces, which were estimated as we had no means for measuring them accurately. But, really, all that we wanted from the tests was to see how well the Tresse Bowline resisted deformation under severe loading and thereafter how easy it was to untie. A large plastic tarp -  folded several times -  covered the entire setup when the forces were being applied. Even so, the high forces reached scared me, as this was the first time either of us has done something like this.   
   The tests were conducted in the normal loading mode. Only two tests were performed, one with 10.5?mm KM (brand unspecified) and the other with 4mm nylon accessory cord. The test pieces consisted of a Double Bowline tied on one end of each test piece and Tresse Bowlines tied at the other ends. The accessory cord was tested to near failure as best as could be judged [~600-750 lbs.], the knots were checked for movement and ease of untying, after which the knots were reset. The accessory cord was then loaded to failure, at which point the Tresse Bowline ruptured. Of course, the highest forces were reached when testing the KM and could have been as high as ~1000 lbs.
   The test results showed that the Double Bowlines and the Tresse Bowlines maintained their forms well under heavy loading and were similarly easy to untie.
   I would like to do more testing to gather some data points regarding movement at or near the knot. FWIW, I will also test the T.Bowline for ring-loading issues and see if I can get it to jam.

Cheers,
alpineer

The puller used was similar to this product.  http://www.texastooltraders.com/Contractor-Supplies/Pullers-Bars/Comalong-Pullers/Maasdam-CAL-1-1-Ton-Capacity-p8447136  (http://www.texastooltraders.com/Contractor-Supplies/Pullers-Bars/Comalong-Pullers/Maasdam-CAL-1-1-Ton-Capacity-p8447136)
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Sweeney on March 23, 2013, 10:16:53 PM
The test results showed that the Double Bowlines and the Tresse Bowlines maintained their forms well under heavy loading and were similarly easy to untie.

Perhaps I'm missing something here but on the face of it the double bowline outperformed the tresse bowline in that the tresse bowline ruptured and the double bowline didn't. That would put the double bowline in pole position awaiting tests against say the EBDB? I have in mind something like the "knot wars" used for fishing knots but I don't have the kit to contribute to testing unfortunately.

Barry
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 24, 2013, 02:57:34 AM
Hi Barry,
   I indicated in my opening post that the tresse bowline appears to be weaker than ABoK #1010. Commercial and sport fishermen and climbers... value many of the same characteristics in their knots. Where each discipline can differ is in what specific characteristics of knots they must necessarily place greater - or lesser - focus on. For a climber, the threat of a knot causing a line to fail from being overloaded is simply unacceptable, so climbing ropes are necessarily overbuilt, and knot strength becomes a lesser factor in knot choice because the required strength is always there in enough measure. Even a weak knot is strong enough for any task, but for other undesirable properties... it may not be used in certain applications.
  One could argue that strength is the most important of all cordage properties. Knot efficiency isn't a major issue concerning climbing ropes because of the high margins of safety built into them. So the focus on specific attributes goes elsewhere.
   Fishermen are at the other end of the scale (haha). Their lines must necessarily be of smaller diameter for several reasons, I would guess (bulkyness, weight, cost, stealthyness, manageability...). Fishing requirements don't allow for overbuilt lines with high strength margins, in fact, in the case of sport fly fishing the name says it all. The focus naturally tends toward knot strength efficiency to get the most performance from their lines.
   So, did you miss something Barry? No, not really. You read correctly. But so what. It is what it is. I'm just reporting my observations as honestly as I can. Why come to conclusions about a knot based on one parameter when there's a host of others to consider? I've just begun the quest to test and prove my claims in a public forum. Pole sitters don't always win the race!
   Everyone here has an opportunity to engage themselves in evaluating this simple adaptation to the standard Bowline.

Cheers,
alpineer 
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 24, 2013, 05:55:20 AM
My thoughts on Bowline security:
   It would be most desirable to get the security feature of a Bowline derived knot up front rather than at the tail end of the tying process. There's a human psychology aspect to my thinking on this. Considering reports of accidents implicating failed Bowlines, I suspect that most were a result of not tying a tail security feature.  Better for the security feature to be first - before tying the Bowline -  rather than last, regardless of whether you feel the need to do something with the tail -  i.e. if you remember to after being distracted, say, by the scenery around you ;), or feeling rushed or for whatever reason. Perhaps those accidents, and the bad press that followed the Bowline, could have been prevented.
   In the tresse bowline's case the first nipping loop is the knot's security feature, after which you're tying ABoK #1010.

alpineer
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 24, 2013, 07:10:37 AM
I'm having trouble with this "Elbow" [capitalized!] structure :
should it be familiar to us?  --else, any references to cite?
--dl*
====

Really?

http://en.wikibooks.org/wiki/Knots/Components (http://en.wikibooks.org/wiki/Knots/Components)
http://www.ropebook.com/information/knots/terminology (http://www.ropebook.com/information/knots/terminology)
http://www.itstactical.com/skillcom/knots/knot-of-the-week-terminology/ (http://www.itstactical.com/skillcom/knots/knot-of-the-week-terminology/)
 
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on March 24, 2013, 02:03:05 PM
   It would be most desirable to get the security feature of a Bowline derived knot up front rather than at the tail end of the tying process. There's a human psychology aspect to my thinking on this. Considering reports of accidents implicating failed Bowlines, I suspect that most were a result of not tying a tail security feature.  Better for the security feature to be first - before tying the Bowline -  rather than last,

   You have a point here. However, why not have a secure nipping structure AND a secure collar structure, at the same time ? Regarding good things, most of the time "two" is better than "one". Bowline is a knot made by two good components : the nipping loop and the collar. If we decide to go forward, it seems reasonable to me to use both feet / to improve the nipping loop AND the collar. When you replace the tyres of your car, either of the front or the rear wheels, you replace both of them, don't you ? I never use one single anchor, or one single mooring line - and I admit there is a human psychology aspect in my thinking on this !  :)
   
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 24, 2013, 07:58:40 PM
   You have a point here. However, why not have a secure nipping structure AND a secure collar structure, at the same time ? Regarding good things, most of the time "two" is better than "one". Bowline is a knot made by two good components : the nipping loop and the collar. If we decide to go forward, it seems reasonable to me to use both feet / to improve the nipping loop AND the collar. When you replace the tyres of your car, either of the front or the rear wheels, you replace both of them, don't you ? I never use one single anchor, or one single mooring line - and I admit there is a human psychology aspect in my thinking on this !  :)

Simplicity, Simplicity, Simplicity. Complicating a structure further generally results in more bulk, more time required for tying, and more opportunities for mismanaging the tying process . At what point do you stop adding complexity to your structure? Do "we" decide to go "forward" further still, and take agent smith's cue and throw in a Yosemite finish? If you feel the need, you have those as options. 
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 24, 2013, 08:08:19 PM
  Simplicity is imperative to me, too

 :o  ;D You had me fooled, X1!
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on March 25, 2013, 05:37:10 AM
  At what point do you stop adding complexity to your structure?

  Good question !  :)
  "I" would say, when "we" decide to move, "we" have to move both feet, just one step each. "I" think that the bowline is a two-components knot - so if "we" decide to go forward,"we" have to tie a more complex nipping structure AND a more complex collar structure. How much "more complex" ?  Nec plus quam minimum.
  Simplicity is a most complex thing do define ! Is an astronomical model that explains the orbits of planets with dozens of more simple cycles and epicycles, more simple than a model that uses only a few more complex ellipses ?
   More to the point, "I" tend to believe that the more complex nipping structure offers safety in relation to strength, and the more complex collar structure offers safety in relation to slippage. "I" have not seen any experimental proof that a double nipping loop, of whatever shape ( be it an Open Elbow, an untwisted or twisted Pretzel, a Clove hitch, a Girth hitch, a Constrictor... ) nips the penetrating eye legs harder and more efficiently than a single nipping loop. "I" think that the double nipping loop is needed for its greater strength and self-stabilizing properties, rather than for its greater gripping power. The main obstacle against slippage is the collar - so, if "we" wish something beyond the common bowline, "we" have to improve the nipping loop AND the collar.
   The two collars offered by the Janus bowlines, the two collars offered by the Double Collar bowlines, like the Mirrored bowline ( a Girth hitch(ed) Double Collar bowline), the braided collar offered by the Braided bowline, the Yosemite finish bowlines, all are means to the same end, a more secure collar structure. The problem is how to combine one of those solutions with one of the solutions that throw the other shoe, that of the safer nipping structure.
    To me, the common or "Eskimo" bowlines are perfectly safe 99 % of the time - so I think we are talking only for the rare rest of the cases, for people that are not going to change their routine, the retraced fig.8, for the next hundred years (at least), for people that do not read any post in this Forum, and for ourselves. So, let us not get too exited in defending our personal beliefs about what would be the best mousetrap.  :)
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 25, 2013, 07:33:32 AM
As for "not critical ...", there should be something definite
said here about dressing --not an either/or/anything-goes
indication, as this seems to be.  (E.g., one could ask for one
form --for checking correct crossings--, and then specify that
this more open form be set into something more compact.
And, yes, it might be that the entanglement tolerates open
or compact dressings --which could be helpful if working with
such stiff rope that compactness was not easily achievable
(thinking of some ornery BW II old rope I have beside me!).)

I definitely prefer the open form, but expected tyers would "instinctively" scrunch the nip. But yes, I was not clear enough in stating that the nip should be left in the open form, although my photo #4 clearly suggests this dressed and set form. Or, I could have stated with more elaboration that it's definitely not critical :). I will try to confirm with more testing.
Were you able to tame that old ornery B W II stuff?   


And among these tests was one (or more) that entailed breaking
the knot, such that your assertion of strength compared with the
(common / #1010) bowline has a basis?  --surprising my guess.
What material was used, and how many tests (for strength)?
(And did you set the knot so (overly) snug as SS369 shows?!)

The first strength comparison tests, admittedly crude, were done with cotton thread of expectedly non-uniform nature (what I had at hand that I could break by hand). Maybe a half-dozen tests were done, enough to satisfy my curiousity for the moment and cause me some mild disappointment re the results. The higher load tests were done with a friend, and used small dia. nylon accessory. The test appartus consisted of a screw-eye in a ceiling beam and a 3 ft. long section of 2x4 placed through the test loop for us to stand on and create the necessary forces to break the knot. Only two strength tests were completed because of the lack of control we had over the test apparatus. A minor injury was sustained by the friend. For safety reasons alone this is not a good means for testing knots.
  Those tests are preliminary at best. I would like to conduct more testing that would support the gathering of more relevant data.

Re: the strength test results, I too, was surprised by the findings.
Re: SuperSnug369 test specs, I believe I did in the cotton thread. The results were the same. I'll retest at some point.


 

Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Dan_Lehman on March 26, 2013, 06:11:22 PM
I'm having trouble with this "Elbow" [capitalized!] structure :
should it be familiar to us?  --else, any references to cite?
--dl*
====

Really?

http://en.wikibooks.org/wiki/Knots/Components (http://en.wikibooks.org/wiki/Knots/Components)
http://www.ropebook.com/information/knots/terminology (http://www.ropebook.com/information/knots/terminology)
http://www.itstactical.com/skillcom/knots/knot-of-the-week-terminology/ (http://www.itstactical.com/skillcom/knots/knot-of-the-week-terminology/)

Really.  (To that first site I put in some corrections --no telling
whether they'll survive ("bitter end" my arse  >:( ).)

I see a helical structure, and don't succumb to dumbing down
to two-dimensional simplistic-ness.

You mention "no torsion" : I suggest that you do your loading
in braided rope and check this --I think you'll see obvious
torsion, with unloaded strands arc'd upwards in obvious
non-tension (there goes 50% !) and the opposite-handed
strands tight.  Once can see this in a fig.8 end-2-end/eyeknot.
Maybe this helps give #1010 its gain (it's lack of loss)?!
(Note that torsion in laid rope should affect the rope as
a whole --i.e., all of fibres gain or lose--, whereas braided
construction has fibres going in different directions!)

Now, the question of "Holy Grail"ness was put in particular
by seeking comparison of the OP knot with the mirrored bowline
--one that seems to have good slack-security and tested-in-HMPE
(lacking final tuck, alas) high-load (to rupture) security
(devoid of SuperSnugging!  ;D ).  --as one example.


--dl*
====
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Dan_Lehman on March 26, 2013, 06:30:09 PM
   It would be most desirable to get the security feature of a Bowline derived knot up front
rather than at the tail end of the tying process. There's a human psychology aspect to my thinking on this.
Considering reports of accidents implicating failed Bowlines, I suspect that most were a result
of not tying a tail security feature.
.:. Better for the security feature to be first --before tying the Bowline--  rather than last,

   You have a point here.  However, why not have a secure nipping structure
AND a secure collar structure, at the same time ? Regarding good things,
most of the time "two" is better than "one".  Bowline is a knot made by two
good components : the nipping loop and the collar.  If we decide to go forward,
it seems reasonable to me to use both feet / to improve the nipping loop AND the collar.

Heinz Prohaska --responding to the infamous (but often mis-told)
Lynn-Hill-falling-unknotted story (she didn't tie her intended bowine)
suggested using the anchor bend (fish.bend) as the base, which
would give a sort of Prohgrip /Blake's hitch grip to the tail inserted
through it --security at first closure of the tie-in eye!  His full knot makes
a "proper collar", IIRC.  Oh, the insertion of the tail to form/close the
eye is in the same direction that it goes in completing the base knot.
That sounds like about as "up front" as one can get --SOMEthing has
to be tied, after all.

For myself, I'm looking at two-stage knots, where the first stage
is some sort of hitch, hoped to be able to serve securely should
everything else somehow fall apart --though one must presume
that that situation implies that the base hitch too will be loose
(for how else ... ?) !  I've come to the conclusion that those
compound knots that don't look so good on this condition
nevertheless give slack-security so great that there is no need
for their being this back-up security element; but there is
one that seems secure when *open* --ironically, it is less
accommodating of forming so secure a compound structure!

These are ungainly and complex-looking, but their tying is
one of building upon simpler elements; the knowledge of
what one is doing should make this feasible.  The payoff
is having a tie-in that (1) securely endures to hold, (2)
might give better load absorption (in not so tightening
that is loses knot-compression), and (3) is easy to untie.


--dl*
====
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on March 26, 2013, 09:44:06 PM
t...wo-stage knots, where the first stage is some sort of hitch, hoped to be able to serve securely should everything else somehow fall apart --though one must presume that that situation implies that the base hitch too will be loose

 A hitch tied on the returning eye leg around the rim of the nipping loop can serve this purpose - so, even if the nipping loop itself opens up, something would still remain closed !

These are ungainly and complex-looking, but their tying is one of building upon simpler elements; the knowledge of what one is doing should make this feasible. 

  If the "nipping structure" and/or the "collar structure", as a whole, happens to resemble a well-known knot, there would be a real or virtual aspect and sense of "simplicity", which would help the average knot tyer to remember how to tie, and to tie, the post-eye-tiable eyeknot utilizing it/them easily - a ready-made pattern, a built-in mnemonic, so to speak. That is why it pays to examine each of the two parts, the "nipping structure" and the "collar structure", as separate entities, although their entanglement into the "compound" finished eyeknot is usually very complex. That is why I have argued that the Constrictor bowline is, in fact, not less simple than the Tresse bowline - or, at least, it is not much more complex, to the point one should not consider it as a practical and convenient solution.
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 26, 2013, 10:25:15 PM

Really?
http://en.wikibooks.org/wiki/Knots/Components (http://en.wikibooks.org/wiki/Knots/Components)
http://www.ropebook.com/information/knots/terminology (http://www.ropebook.com/information/knots/terminology)
http://www.itstactical.com/skillcom/knots/knot-of-the-week-terminology/ (http://www.itstactical.com/skillcom/knots/knot-of-the-week-terminology/)

Really.  (To that first site I put in some corrections --no telling
whether they'll survive ("bitter end" my arse  >:( ).)

I see a helical structure, and don't succumb to dumbing down
to two-dimensional simplistic-ness.

You mention "no torsion" : I suggest that you do your loading
in braided rope and check this --I think you'll see obvious
torsion, with unloaded strands arc'd upwards in obvious
non-tension (there goes 50% !) and the opposite-handed
strands tight.  Once can see this in a fig.8 end-2-end/eyeknot.
Maybe this helps give #1010 its gain (it's lack of loss)?!
(Note that torsion in laid rope should affect the rope as
a whole --i.e., all of fibres gain or lose--, whereas braided
construction has fibres going in different directions!)

Now, the question of "Holy Grail"ness was put in particular
by seeking comparison of the OP knot with the mirrored bowline
--one that seems to have good slack-security and tested-in-HMPE
(lacking final tuck, alas) high-load (to rupture) security
(devoid of SuperSnugging!  ;D ).  --as one example.


--dl*
====

   It's better for your health and well-being to succumb to "two-dimensional simplistic-ness" than to bitterness, Dan. ;D I stated at the beginning of this thread that the proper elbow contains 720 deg. line torsion. I also see a helical structure. The tresse bowline has no helical structure (certainly not in the same sense). The line's construction is of no matter in the context of this discussion.
   The tresse bowline's elbow is not a "proper elbow". Nevertheless, it's as legitimate a structure as any other elemental form from which knots are built, and deserves to be acknowledged as such. It needs a name, and because of it's two-dimensional resemblance to the proper elbow (but without torsion) I call it open elbow. It doesn't contain any torsion*. Have you not coiled a power cord using the alternating handedness method? The coils exhibit local line torsion only. Throw the coils back out and all that torsion diappears, period. The "tressed elbow" elemental form doesn't contain even local torsion.

* Unless you want to be nit-picky about the small amount of torsion initially required for a three-dimensional linear structure to cross itself, it's perfectly reasonable to ignore this incurred torsion.

 

Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: James Petersen on March 27, 2013, 02:06:57 AM
I'm having trouble with this "Elbow" [capitalized!] structure :
should it be familiar to us?  --else, any references to cite?
--dl*
====

Really?

http://en.wikibooks.org/wiki/Knots/Components (http://en.wikibooks.org/wiki/Knots/Components)
http://www.ropebook.com/information/knots/terminology (http://www.ropebook.com/information/knots/terminology)
http://www.itstactical.com/skillcom/knots/knot-of-the-week-terminology/ (http://www.itstactical.com/skillcom/knots/knot-of-the-week-terminology/)

Really.  (To that first site I put in some corrections --no telling
whether they'll survive ("bitter end" my arse  >:( ).)
==
... "in ignorance of its history" didn't make it through the review -- guess it wasn't politically correct.  ::)
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 27, 2013, 06:40:13 AM

Quote
WARNING!  It should go without saying, but nevertheless it cannot be overstated,
--from none to all !!   ::)
 

Wrong. "from none" would be "It goes". Such criticism! Over nothing. Or am I being too sensitive? :-\

alpineer
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 27, 2013, 06:54:05 AM
It's doubtful that a particular Bowline will ever be discovered that would achieve
"Holy Grail" status, but I would argue that the Tresse Bowline can come closest
to the ideal "Bowline for all Reasons", more than any other.


 :)   I'm remiss in not asking : do "all Reasons" go beyond practical ?!!

--for this thread to be in (mere) Chit Chat and not Practical forum!
(--or Explorations..., New...)


 ;)

 ;D Yes, you would be remiss! No qualms here over it being moved to Practical.
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 27, 2013, 08:08:34 AM
Of particular interest to me is how the knot would perform in HMPE Spectra/Dyneema.
Any takers?
For starters, there is the doubt that knotting such material
is at all worthwhile in terms of strength --all testing of it
so far has cast doubt as to knots being anywhere reasonably
strong as we would expect, from historical materials.
Of particular interest should be this video of Brion Toss's test
of not-quite-my-recommended "mirrored bowline" --he omitted
the reflected collar, alas--:
www.youtube.com/watch?v=Fy6Y2Xoo4Ak (http://www.youtube.com/watch?v=Fy6Y2Xoo4Ak)  [ in 5/32" HMPE 12-strand ]
.:. the eye knot holds, but breaks at what Toss guesses
is not-so-high load --the device wasn't calibrated(?!).

Yes Dan. But it's the Spectra Bowline 1 test video http://www.youtube.com/watch?v=ZFRQcExLA34 that I'm interested in for the very reasons you quote. I want to know; will the Tresse Bowline hold the eye's size and capture more of that elusive strength component?

alpineer

Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Dan_Lehman on March 27, 2013, 05:56:11 PM
Yes Dan. But it's the "Spectra Bowline 1" [= dbl.bwl + stopper] test video
http://www.youtube.com/watch?v=ZFRQcExLA34
that I'm interested in for the very reasons you quote.
I want to know; will the Tresse Bowline hold the eye's size and
capture more of that elusive strength component?

alpineer

Note that the double bowline shown in this video has its tail
stoppered (with what appears to be an overhand knot) ; IIRC,
that was not the case with the incomplete mirrored bowline (!).
Perhaps the "tresse bowline" --or the like knots I've shown above--
will tighten upon its SPart so as to prevent the material from
being drawn out under loading.  (Btw, I wonder how the knot
so slipping will behave in dynamic loading --I don't believe that
the slippage will become adequately fast ... !)  But one can't
hold much hope for strength, given the hard U-turn, I think.
(My hope for the "locktight" eyeknot's strength looks to there
being enough friction within the coil to draw off load over the
rather broad area of compression --perhaps something that,
if possible, varies with rate of loading : dynamic loading cheating
this hoped-for frictional assistance?)


When I saw this video, I was shocked --all bets were off,
my ideas of strength-building / material-behavior shattered :
"Huh, it can DO this??!".   :o
I could see that the gradual-bends tactic would amount to just
some wavy route to the U-turn w/o consequence (or maybe
there would be a price in torsion to pay!), just as running
a line over a good block puts in a U-turn but hardly diminishes
the force delivered beyond this point (i.e., no off-loading of
force in the block).

So, I didn't hold out much hope for what were already quite
inefficient-in-material-use knots of a tortuous SPart path
hoping to offload force over its long run --no, that would
all slide too well.  I did test one knot with such a *theme*,
but whereas I had in mind testing the fig.9 eyeknot (which
one test report suggested --knot name wasn't clear-- had done
well (for HMPE, which means about 50% !)), I opted to load
this structure in reverse, looking at that geometry being
one that gave a broader initial U-turn, and then ... <just hope?>.

In fact, this was my strongest knot in the test of 5 eyeknots;
but only by so much, and absolutely nothing to shout about
(= +/- 42% of "capwrap" tensile --a precise-looking value),
with others in the range from 33%-ish).

Interestingly, it appears that the break in the reversed fig.9
eyeknot came a little past the U-turn --or late in the turn--,
at a point where compression against the eye legs was great,
and maybe some movement added a kick of frictional heat?
(see attached photo of the broken & opp-end unbroken,
equally tied & pulley-set knot, thread-marked [nb, Agent_Smith :
Dan takes his own medicine!  :P  --to some benefit, yes?!] )

In the attached photo, one can see the absence of the
ruptured SPart (lower knot) in the void of the *interior*
of twin strands flowing from the left through twin collars
(these are the U-turn of the eye legs --remember, it is
the reverse of the better-known "fig.9"),
and around and up over the knot to wrap the eye legs.
It appears that the break comes after a half-wrap?!

My thread-marked points are color coded, and as follows:

W) white threads (bit yellowed in image, a white-balance issue)
mark the point where the SPart & resp. eye-legs exit the knot;
these will show how much material yield there is on knot
compression, and any slippage (I think that most reports
call this "slippage" which to me seems wrong-headed --there
must be some feed out of material when the knot compresses,
but I don't see that as "slippage", which has connotations
of insecurity --but perhaps its all a matter of balance, hmmm?!).

P) Pink-red threads --one per knot-- mark the suspected
point of rupture (my surmise (what have we learned if we
can't surmise accurately --and the guess & test game should
be an iterative one of improved surmise!).

G) Golden threads mark a 2nd-guess rupture point,
based on some surmise of the yield of material to compression.

What I see in this photo is that the SPart entered the nub,
moved rightwards -> upwards -> back downwards -> and
then in coming up around towards the viewer broke at
about the low point of this wrap, as viewed.  The puff of
white ruptured fibre ends will fold down to about this
point, and the examination of the broken SPart vis-a-vis
its markers with the intact upper knot similarly tied &
loaded also place rupture here.

The P threads started out nearly where the G threads are
at rupture --I'd say that they were just a little before
this point (i.e., slightly closer to exit, roughly right atop
the 2nd-crossed (SPart flowing into nub) twin eye leg).
And the break was even farther along the SPart's path
than this point, by about a half wrap (180deg).

Note that eye legs pulled out just a little, evenly.  And
perhaps the only real measure of "slippage" is the white
thread at the tail --was it pulled into the nub?  Here, it
is not; perhaps a mm or two at most.


--dl*
====
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: alpineer on March 30, 2013, 07:38:08 AM

It is interesting to note that the very similarly curved SPart
of the knot (my "#56" shown in my next msg.) broke only
1 strand but had the same strength; one might have thought
that if the forces could be so evenly apportioned to break two,
it would almost necessarily be at a greater force!  (Perhaps
there are other factors at work to explain these results.)]


I would surmise that a second strand was on the verge of failing just before the first strand failed. Beyond that, I would think there's not much to say which would be of any statistical significance from a single sample.
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on April 05, 2013, 01:45:06 AM
   I have tested the four variations of the Tresse bowline : the "left" and the "right" hand ones, and the "under" and "over" ones ( "under" / "over", regarding the way the first diagonal element of the "8" shape nipping structure crosses the second - the variation shown at the first post is the "under" ). I can confirm that this nipping structure is very stable, and grips the penetrating segments very efficiently, EVEN WITH A LOOSE COLLAR. The mere presence of the two legs of the collar, even if they are not tightened, is sufficient to keep the returning eye leg in place. I have seen that the "under" variation is better, indeed, because the standing part remains closer to the axis of loading of the returning eye leg, and does not twist it as much as it does in the "over" variation. I have also seen that the tail of the "left hand" Tresse bowline is squeezed more efficiently by the standing part s first curve, AND by the returning eye leg s first curve ( the variation shown in the first post is the "right hand", which I believe is a little inferior regarding that matter ).
   So, I believe that all that is needed in order to have a "safe" bowline, is a more safe collar. The only way I have been able to improve the collar, and retain the basic element of this bowline, its double nipping structure, is the braided collar shown in (1), copied from the ingenious "Braided Bowline" presented at (2).

1. http://igkt.net/sm/index.php?topic=4321.msg27020#msg27020
2. http://igkt.net/sm/index.php?topic=4283.msg26651#msg26651
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Luca on April 15, 2013, 01:41:28 AM
Hi,

A banal idea: to make Inuit/ Eskimo forms for the versions of the knot's nub of the Tresse Bowline:to do an example,the diagram below shows a(corresponding to type A(because I want to give a chance also to the losers)) Inuit/Eskimo "translation" of a left handed+"over"(or"improperly dressed"Doubled Cowboy Bowline) Tresse Bowline(OK I admit it: I did not feel more than continue to ruin the thread of Alan Lee, so I decided to start doing it with the thread of Alpineer, to which I apologize right away);I do not know if it adds something to a normal Inuit / Eskimo or to a "regularly dressed" Doubled Inuit / Eskimo.

                                                                                                                             Bye!

(http://)

Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Luca on April 15, 2013, 01:44:58 AM
I am not able to attach more than one image in one post: the complete knot is this:

(http://)
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on April 15, 2013, 12:29:45 PM
   Is this your loop, Luca, or not ? If it is, it is a fine variation of the 8 Loop, shown at (1), so I guess you should keep doing what you have been doing there ( you will be much welcomed !  :) )
   A problem with those tight "Eskimo"- like loops is that, even under moderate loading, they would clinch around their compact nub and they could jam - while the elongated common bowline - like loops, as the Tresse bowline, would not.

1. http://igkt.net/sm/index.php?topic=4340.msg27168#msg27168
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Dan_Lehman on April 15, 2013, 05:08:21 PM
I am not able to attach more than one image in one post: the complete knot is this:

Really?  I wonder why not --how does this IGKT
system fail to work for you (but works for others)?

The knot you show is an eye-knot correlate to one
variant of Lapp knot end-2-end knots.  You should
find that the variation jams.  A way towards getting
a knot that can be pried loose (by pulling tail and
tail-side eye leg apart, to pry IN some SPart material)
is to have the tail-side of its collaring bight --i.e.,
that part after its U-turn heading straight out
through the SPart's turn-- go outside of all of
the SPart wraps until its tuck out through the
turn.  The wraps, then, won't bing this tail,
enabling it a fighting chance at working as the
lever to pry out some SPart, and thus liberating
itself, and untying.

Conceivably, the SPart wraps will just bind too
tightly; but, often, the loosening is possible,
as one is pulling (initially) the SPart straight
out, with no deflections in its path to impede
such movement --and you need only enough
to free the nip on the tail.  In the end-2-end
knot, the SPart's tail won't be loaded, so there
should be a little less tightness in its wraps.



--dl*
====
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Luca on April 16, 2013, 01:11:26 AM
Hi X1,

   Is this your loop, Luca, or not ? If it is, it is a fine variation of the 8 Loop, shown at (1), so I guess you should keep doing what you have been doing there ( you will be much welcomed !  :) )
 
1. http://igkt.net/sm/index.php?topic=4340.msg27168#msg27168

I thank you again, I'm glad I made a decent knot for once!(well, after the cockroaches and various junk I have presented, you are fully empowered to think that I gave money to someone for secretly pass to me a knot to show it as "mine"...but I did not understand: If the loop is by someone else becomes something else? :D)
In fact I have started from a simple idea to make an Inuit/Eskimo version of the Tresse Bowline , and from there I started to fumble;now that you mention it, in fact, there are similarities with the 8 Loop; I noticed that just by appropriately changing the way the second leg of the collar enters the nipping turns I get a knot nub's very similar, but arranged in "common bowline sauce"(I did not expect this!).
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Luca on April 16, 2013, 12:32:55 PM
   Is this your loop, Luca, or not ?

Or perhaps yours was instead a reference to a couple of unfortunate loops that bear my name without having a guilt?

A problem with those tight "Eskimo"- like loops is that, even under moderate loading, they would clinch around their compact nub and they could jam

The knot you show is an eye-knot correlate to one
variant of Lapp knot end-2-end knots.  You should
find that the variation jams.  A way towards getting
a knot that can be pried loose (by pulling tail and
tail-side eye leg apart, to pry IN some SPart material)

It is true, I actually quite easily untie this loop, but not acting more immediately on the tail, as it should be the most direct and fastest way to untie a loop, but that in this case is too tight to be pulled out easily, if not before I act by pulling on the portion of the rope adjacent to the first eye leg,that passes through the collar's bight;but, thinking about it, if, during the loading of the loop, it happens that the second eye leg pull tight the collar's bight around this portion of rope,before the tail is closed (too) strong,as is more likely to occur in the bend version, also this operation may become difficult.

I am not able to attach more than one image in one post: the complete knot is this:

Really?  I wonder why not --how does this IGKT
system fail to work for you (but works for others)?

I do not know where I'm wrong! Saves only the last selected image

A way towards getting
a knot that can be pried loose (by pulling tail and
tail-side eye leg apart, to pry IN some SPart material)
is to have the tail-side of its collaring bight --i.e.,
that part after its U-turn heading straight out
through the SPart's turn-- go outside of all of
the SPart wraps until its tuck out through the
turn.  The wraps, then, won't bing this tail,
enabling it a fighting chance at working as the
lever to pry out some SPart, and thus liberating
itself, and untying.

Thank you!Is that so?(Below)

                                                                                                                           Bye!

(http://)


Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on April 16, 2013, 12:34:35 PM
  If the loop is by someone else, does it become something else? :D)

 I guess not !  :) There are many knot tiers who have not yet noticed this simple fact, I am afraid...

   Is this your loop, Luca, or not ?
Or perhaps yours was instead a reference to a couple of unfortunate loops that bear my name

   No, I was not sure about the spatial order of lines, at the point where three of them are superimposed, and it is difficult to tell witch goes over or under which... I believe it is better to draw the knots without such "triple" points.
   ( The Luca s TIB bowline, where the collar structure is a fig.8 knot entangled within the nipping loop, is a very secure / very nice post-eye-tiable AND tiable-in-the-bight eyeknot ! )
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on April 16, 2013, 12:59:08 PM
Thank you ! Is that so? (Below)

   I do not know who ordered this knot, because I have not been able to pay a visit to the Oracle of Delphi lately (1)...
   However, I think it is a very secure and nice knot - which will not jam so easily as the previous one.(*) ( Although it is not related to the Tresse bowline any more - it is a variation of the "Eskimo" bowline, where the single nipping loop is transformed into a 540 degrees coil ).

   (*) Noope ! It jams, as easily as the previous one ! I have now submitted it in the same torture as the previous one ( same amount and pattern of loading, same rope ), and I know !  :)

1. http://en.wikipedia.org/wiki/Pythia
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Dan_Lehman on April 16, 2013, 08:16:02 PM
I am not able to attach more than one image in one post: the complete knot is this:

Really?  I wonder why not --how does this IGKT
system fail to work for you (but works for others)?

I do not know where I'm wrong! Saves only the last selected image

This sounds as though you are clicking the wrong space
for the subsequent files --you need to click the spot
for attaching another file and not the one with a filename
listed beside it (which, as you've seen, will replace that
first-named file with the new (which can be useful to
correct a mistake)).  Look more closely at your options!


Quote
A way towards getting
a knot that can be pried loose (by pulling tail and
tail-side eye leg apart, to pry IN some SPart material)

is to have the tail-side of its collaring bight --i.e.,
that part after its U-turn heading straight out
through the SPart's turn-- go outside of all of
the SPart wraps until its tuck out through the
turn.  The wraps, then, won't bing this tail,
enabling it a fighting chance at working as the
lever to pry out some SPart, and thus liberating
itself, and untying.

Thank you!Is that so?(Below)

Close : I see myself tying to a bight, not a loop which
is more what your drawing shows in its crossed legs.
The draw of the SPart should bring the tail with it
up against the other parts.  And X1's exclaimed "nope"
can be discarded to the pile of his others; "yep" is fine,
but high loads and various conditions leave the judgement
to one of tools and forces for untying --"YMMV".  The
advantage is the pulling pretty well aimed at a part
running straight, although tightly bound w/wraps;
and just to gain enough material to enable loosening
--not immediately "loose" after merely prying.
(Elastic line might be the more difficult.)


--dl*
====
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on April 16, 2013, 08:47:48 PM
X1's exclaimed "nope" can be discarded to the pile of his others; "yep" is fine,
but high loads and various conditions leave the judgement to one of tools and forces for untying --"YMMV".

  The knot shown at the pictures I have shown, is not "yep, fine"... unless one belongs to the "over 105 kgr" weightlifting class (and use to bend coins with his fingers...), or belongs to the "light flyweight" wrestling class - although it would be more than "yep, fine", indeed, if one could belong to both those Olympic athletic disciplines- not possible under the present rules, I am afraid.
  I do not believe that there is an objective way we can tell if one knot jams or not - but I was under the impression that, when we are forced to use tools to untie it -any tools -, we are talking about a jammed knot. I had loaded the knot shown in the pictures ( tied on the same 8mm cord I had tied the previously presented one ) with my weight, and submitted it to 8 bounces / jumps - then, to untie it, I was forced to use a pencil as a marlinspike. Even when the "higher" turn of the coil is released, the "lower" one holds very tightly, because the "Eskimo" s collar does not allow any material be inserted into it - and it does not allow it, because itself it is constricted and immobilized by the tensioned standing part s first curve / bight, so it can not be eased even a little bid...
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Dan_Lehman on April 17, 2013, 04:48:13 PM
X1's exclaimed "nope" can be discarded to the pile of his others; "yep" is fine,
but high loads and various conditions leave the judgement to one of tools and forces for untying --"YMMV".

  The knot shown at the pictures I have shown, is not "yep, fine"...

Noting that that image shows the tail on the opposite
side from what I've recommended --and when, e.g.,
tying to an eye, whose legs are both loaded, one should
*model* a leg-free bight by putting such slack into
the side first drawn by the SPart--,
I'm a little surprised that you don't find enough
ability to loosen the SPart-side eye leg,
for I'd expect the collaring bight to not be drawn
so tightly given the SPart's nip of it; but you do say
"bouncing", and that can do the tightening!  (And
this way isn't what I see as the knot's "forcible
loosening" avenue, anyway.)

Quote
I do not believe that there is an objective way we can tell if one knot jams or not;
but I was under the impression that, when we are forced to use tools to untie it
--any tools--, we are talking about a jammed knot.

Well, I see "jammed" in a couple senses.  The first is
that the knot will stay tied when slack, which can be
a highly desired atrtribute; this need not exclude there
being a method for untying the knot, reliably.  THIS
knot's corresponding end-2-end knot I believe fits
this criterion pretty well, with some vagaries per
material(s) and forces.  And then there is the sense
of "welded", where tools and maybe not even tools
only can untie it.  (I recall being happy to find that
I could fit the fairly pointed tip of a pulley hook into
a part of a knot and use the 5:1 MA to haul it loose!)

There is some merit to being able to at least untie
using tools, maybe in a not so difficult manner,
but mostly to get one's man-sized force up to the
rope-sized forces (think, large lines).  --as contrasted
with the rather hopeless cases of "jammed".


Quote
I had loaded the knot shown in the pictures ( tied on the same 8mm cord
I had tied the previously presented one ) with my weight,
and submitted it to 8 bounces / jumps;
then, to untie it, I was forced to use a pencil as a marlinspike.

--a pencil qua marlinespike??!!!  Wow, that
sounds quite feeble!  * * S N A P * *

I'll later give this a try with relatively frictive (age)
7mm kernmantle, whose smoothness should enable
fairly severe tightening, yet whose frictiveness impede
the movement I hope to see.  AND, to show that I'm
not so confident of success, my pulley will be applied
deliberately at lower effect first, and only increase if
successful.

Still, I think that for many applications, one can already
see utility in the end-2-end version, where the main
goal is slack-security.  (In my pocket, this knot qua
bight-hitch in 3/16" silky flexible nylon solid braid
regularly loosens tied around thinner binding cord
--essentially, a knot that is a stopper-ish one tightened
by itself (the binder cord hardly adding much of bulk);
and #1425 joining the ends of the solid braid also
gradually loosens after being set tight.


--dl*
====
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on April 17, 2013, 09:40:37 PM
Noting that that image shows the tail on the opposite side from what I've recommended

   I have just followed Luca s interpretation of Oracle s "description" ...

   I'm a little surprised that you don't find enough ability to loosen the SPart-side eye leg, for I'd expect the collaring bight to not be drawn so tightly given the SPart's nip of it;
   but you do say "bouncing", and that can do the tightening! 

   It did nt move ( a hundredth of ) an inch ! The Standing s part nip immobilized it, and that, by its turn, was immobilized by the lower coil.
   The " bouncing" / alternating loading can make a difference, indeed. The jamming mechanism of the reversed Buntline hitch (1) was a revelation to me... The two ends of the jammed tangle ( the limbs of the Clove hitch) leave the nub towards opposite directions, while, at the same time, they are squeezed upon each other by the tensioned "bridge" ( the riding turn of the Clove hitch ) that encircles them. At each "bounce", any portion of the rope that, at the peak of loading, manages/suceeds to be pulled out of the tangle, however small it might be, reduces the remaining rope length inside the tangle a little bid more - so the "bridge" gets shorter and tensioned even more, and it pulls and then pushes the two ends of the tangle the one upon the other even more forcefully. With each "bounce', the friction forces between the two ends are getting stronger and stronger - in fact, they become so strong that the two ends themselves become almost "geared", and coupled to each other : any small portion of rope that is released / set free by the one, is automatically gathered / enslaved by the other : a rope-made racheting device, that can only reduce the total amount of rope length within the jammed tangle, just because nothing can get inside this most tight "gate".
  The jamming of the adjustable loop based on the reversed Buntline hitch, this rope-made racheting mechanism, has offered me a most valuable lesson that I was not able to receive from anywhere else. In the light of it, I can now understand / explain much better the "miraculous" ability of the Gleipnir to "lock" within its bights any accumulated tension inserted into them by the pull of the two opposing ends. I advice any interested kmot tyer to tie this most simple knot, the adjustable rev. Buntline loop (1), submit it to a heavy "bouncing' / alternating loading, and, for once, enjoy the jamming of a knot, that he will now understand / explain !  :)

--a pencil qua marlinespike??!!!  Wow, that sounds quite feeble!  * * S N A P * *


  Nooope ! No shear forces ! Just compression. Use the pointed conical shape of the pencil to pin it into the jammed knot s nub, i.e. use it as a nail, and so force the widening of a previously tightly shrank opening. We can consider a cone as a 3D wedge - and a wedge is a "simple machine", that uses its small angle to gain a mechanical advantage. I guess that this fact was implemented in sparrows, hooks and arrows, well before the tying of any jammed knot !  :)

   I do not deny that this is an interesting, secure and nice knot ! However, now we have its non-jammable twin, the original 8-loop, that is also very easy to remember how to tie and to tie ( to my view, it is even easier - but perhaps I am biased on this...), why we will ever have to risk by tying the jammable variation ?   

1. http://igkt.net/sm/index.php?topic=4347.0
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Luca on April 21, 2013, 12:16:08 AM
Hi,

I'm sorry, nothing significant to write, and I write it also delayed due to lack of time + connection problems that I encountered in these last days.

   Is this your loop, Luca, or not ?
Or perhaps yours was instead a reference to a couple of unfortunate loops that bear my name

 No, I was not sure about the spatial order of lines, at the point where three of them are superimposed, and it is difficult to tell witch goes over or under which... I believe it is better to draw the knots without such "triple" points.

Uuh.. just now I get it! Your doubts was related to whether the photos you showed in that post (with regard to them I have forgotten to thank you)were corresponding to my diagrams; now everything makes sense! (I'm sorry, I did not realize, I thought your were a joke,due to the fact that it seemed strange that I showed an acceptable loop!)

( The Luca s TIB bowline, where the collar structure is a fig.8 knot entangled within the nipping loop, is a very secure / very nice post-eye-tiable AND tiable-in-the-bight eyeknot ! )

It's just what I said: a deserving loop..which must bear my name ...poor fellow loop!


This sounds as though you are clicking the wrong space
for the subsequent files --you need to click the spot
for attaching another file and not the one with a filename
listed beside it (which, as you've seen, will replace that
first-named file with the new (which can be useful to
correct a mistake)).  Look more closely at your options!

Indeed it is written: "MORE ATTACHMENTS": I'm just a block-head! Thank you for having the patience to explain to me!

Close : I see myself tying to a bight, not a loop which
is more what your drawing shows in its crossed legs.
The draw of the SPart should bring the tail with it
up against the other parts.

OK, I take the opportunity to show a further correction of my diagram, + a diagram of what may be the corresponding "Common Bowline version" of the loop that I showed at reply # 46, performed with the intent to show (following the line of Alpineer in his first post) a(perhaps) useful way to prepare the nipping turns,and(as actually I only realized last night, due to a link posted by Sweeney from another thread!) then "modelling" to get  the # 97 http://igkt.net/sm/index.php?topic=4321.msg26999#msg26999 (i.e. it does not show the # 97 setting(is more corresponding as initially I set the knot,in a more "compact" manner,similar to the Inuit/Eskimo version), but a way that however might be helpful to get there).

                                                                                                                Thanks again, and bye!



(http://)





   
 
 



Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Dan_Lehman on April 21, 2013, 06:00:50 PM
... then "modelling" to get  the # 97 http://igkt.net/sm/index.php?topic=4321.msg26999#msg26999 (i.e. it does not show the # 97 setting(is more corresponding as initially I set the knot,in a more "compact" manner,similar to the Inuit/Eskimo version), but a way that however might be helpful to get there).

Oh, that's hardly my #97 --which is, after all,
a significant re-dressing of the double bowline
(so, one can see that dressing is critical to getting it right).

Glad you're now past one-attachment-per-post limit.   :)


--dl*
====
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on April 23, 2013, 04:17:03 PM
   The first two pictures show the Luca s Nice Jamming Loop - it is a pity that it jams, but it does jam, no question about it.
   The third picture shows Luca s Non-Lamming loop. Not very different from the Tresse bowline itself ( in fact, it may be considered as a variation of the Tresse bowline, where the tail and the continuation of the returning eye leg are crossed ) - or even from the 8 Loop, shown at (1) and at the fourth picture : more "common" bowline-like, in comparison to the 8 Loop, which is more "Eskimo" bowline-like. I hope Luca is going to actually test those two variations, and report his results to us.

1. http://igkt.net/sm/index.php?topic=4340.msg27168#msg27168
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Luca on April 24, 2013, 11:50:59 PM
Hi,

   The first two pictures show the Luca s Nice Jamming Loop

If Dan Lehman takes the matter with humour :D, I'd say that "Oracle loop" continues to go well as the name for this loop ...

A bowline similar to the OP's, which can be seen as but
a re-dressing of the double bowline into a helical geometry,

    "under" / "over", regarding the way the first diagonal element of the "8" shape nipping structure crosses the second

that's hardly my #97 --which is, after all,
a significant re-dressing of the double bowline
(so, one can see that dressing is critical to getting it right).

    The third picture shows Luca s Non-Lamming loop

Same thing for this other loop: "Dan Lehman # 97" or "Over Tresse Bowline" should be more appropriate names(I had also written: "improperly" dressed Doubled Bowline),since I personally have only reproposed the above scheme of this loop as an attempt to get the setting shown by Dan, through the construction of the nipping turns shown in this diagram,in imitation/aping of alpineer,as he did in his first post: http://igkt.net/sm/index.php?topic=4321.msg26983#msg26983

  I hope Luca is going to actually test those two variations, and report his results to us.

The tests that I am able to make myself, are worth very little, I believe, and then these loops actually are not "mine" ...I guess that  the onus of proof is competence of others in this case!(for what it's worth (nylon (I think), about 9mm braided rope):
-So called"Luca s 8 loop(poor fellow)":quite easy to untie (in one way or another, I swear!)
-So called"Oracle loop":very hard to untie even with tools (Dan, see above for the reliability of  my tests, but .. I swear!)
- # 97/Over Tresse:easy to untie
- Original 8 loop: quite easy to untie(but I also had feelings similar to those of SS369: I saw the tail "come alive" during the loading .. I swear!)(EDIT: Again, I'm not a good experimenter knots: After making further observations I concluded that in fact the tail of this loop does not behave in a manner substantially different from the  tail of a normal Inuit / Eskimo or other similar loops in tend to "move" or to "curl"during the loading.I apologize to X1.) )

                                                                                                              Bye!                                       
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Luca on May 20, 2013, 12:56:15 AM
Hi,

An attempt of "variation on the theme" of the Tresse Bowline (but I do not know if it really adds something) + relative Inuit / Eskimo version (a bulky loop, but not jamming with respect to the Eskimo-like loops shown on the previous page of this thread).

                                                                                                              Bye!



(http://)

Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on May 20, 2013, 08:33:32 AM
   You take a two-turn double nipping loop, and you "twist" the "higher" turn, and/or the "lower" turn, and/or both, 180 degrees. Then, you tie a common or an "Eskimo" bowline s collar. One of those variations is the ABoK#1013 - two others are the bowlines you show here. (*)
   A first problem is that those "twists" force the standing part to follow sharp curves, which absorb a large portion of the nipping loop s constricting power. Notice that the standing part s curves at the Tresse bowline, or at the 8-loop and the 8-8 loop, are much smoother.
   A second problem is that the nipping structure becomes much more complex, but the collar structure remains as simple as it is in the standard bowline. There is no theoretical reason or experimental proof that a complex double nipping structure would nip the tail harder than a simple single one. So, if this complex nipping structure is just wrapped around itself, but, at the same time, does not induce some severe deflexion on the path of the tail that penetrates it, its contribution to the bowline s security would be negligible, or even nil.  ( A tail that follows sharp curves inside a complex nipping structure slips less easily than a straight one - we can say that, in a way, it is "hooked" inside the knot s nub...),
   Sharp standing part s curves, smooth tail s curves, that is the problem !  :)     

(*) P.S.  In just the same way, the 8 - loop is not but a "twisted" Eskimo bowline - so, before we measure its behaviour, we can not say if it is more secure ( regarding a slippage of the tail ) than a simple "Eskimo" bowline, or not...
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: Luca on May 26, 2013, 01:04:27 AM
Hi X1,

Rather than the use in Common Bowline sauce of this nipping structure(The twisting of the turn(s) of a double nipping turn is a perfectly legitimate way of looking at it, although I personally have started from a 8 form, and thus giving it an elongated shape, so to soften the sharp curves, and so encourage greater bending of legs of the collar), which I too thought that did not add any advantage with respect of the Tresse Bowline, I was actually more interested in the Inuit/Eskimo version,which in each case  takes advantage of the curve that is formed when the second leg of the eye returns through the nipping structure.
I am aware of the fact that here I too modify ,making them more complex,the nipping  structures continuing to leave for these eye-knots simple collar structures,but this is because, at least here, I'm interested in maintaining for these loops, the same number of sequences that are necessary to untie a standard Bowline.
Also I was focused on avoiding that an Eskimo-like loop can jam , because sometimes I happened to have some little difficulty to untie even standard Inuit / Eskimo bowlines (of which tails move during a normal load, but without retreat ,as it seems to me, and so it seems to happen even with the 8 loop:so, nothing serious!),but in the above case of the so-called doubled crossing Inuit maybe this is equivalent to a lack of significant increase of security against the risk of slipping compared to normal Inuit / Eskimo bowlines.

                                                                                                                     Bye!
Title: Re: In Search Of The Holy Grail Bowline: A Bowline For All Reasons
Post by: X1 on May 26, 2013, 07:08:41 AM
   I ... have started from an 8 form

  Follow the tail-side eye leg, or the tail itself, in any of your two loops : it enters into the "first" eye of this 8 from the one side of the loop, say, the "front" side, it exits from the other, the "back" side - and then it enters into the "second" eye of this 8 also from the "front" side, and it exits also from the "back" side. Doing this, it passes by the "side" of the 8 s crossing point, it bypasses it, it does not go "over" or "under" it. That is the difference of your loops with the Tresse bowline and the 8-8 loop - which are not only "8" shaped, but "$" shaped as well !  :)