Author Topic: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes  (Read 146032 times)

agent_smith

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #60 on: December 29, 2008, 03:49:30 AM »
Dan, I have read one part of your post in detail...

Quote
GRATUITOUSLY COMPLEX ;  TOO CLEVER BY HALF ! !
--especially regarding tying it:  the more tucking you require, the more of a pain in the ass
it is to do, and the people who will do it, and fewer times they do so!  And, not so effective re security.

and;

Quote
The EBDB's end-binding wrap doesn't work so well on a single Bowline, as it wraps around
just 2 diameters, which is a poor, non-circular-like bending.  One CAN orient the end so that
it wraps around the end-side eye-leg, and thus gains a diameter, and holds better.  But if one
is going to this trouble, I think it's worthwhile to use the EBDB, which should still hold better
(and itself allows for the inclusion of the eye-side eye-leg, but that I think goes into excess
bulkiness and diminished/dubious returns in behavior).

Okay, I am looking closely at the structure of the EBSB. The binding loop appears (to me) to wrap around 3 rope diameters. I am counting the tail as one of the diameters. My tying method illustrates that the tail passes underneath the binding loop and then exits through the collar. I see this as three rope diameters.

I also don't think it is that complex. I find the janus variant more complex! There are degrees here.. and I think it might be a spacial/geometrical problem solving issue - with some people being better at solving 3D geometric problems than others. I tend to think that since the Yo/Bowline is already so popular (particularly in USA), the concept of tying a yosemite finish is well known and proven to work in the field. Adding the extra binding turn through the structure should not present too many technical difficulties for the masses. Again, these are only my views...

I also agree that there will never be just; one knot to bring them all and in the darkness bind them! There will always be a need for several knots within a toolbox of knots. I see the successful variant bowline as having perhaps several roles - one being a tie-in method for climbers. Other uses could include; stretcher attachment knot, and method of anchoring a rope to a tree.

Which brings me to a point about the key salient features I am looking for in this 'holy grail' of knots:

[ ] A desirable trait appears to be the tactic of placing more than 2 rope diameters into the nipping loop(s) re Dan Lehman's technical genius of his EBDB variant.
[ ] The knot must be easy to untie, even after repeated high loadings
[ ] The knot must not be too bulky
[ ] The knot should have the least possible number of tucks/turns and/or movements to complete its structure - that is, be of relatively low tying complexity (which in turn makes it reasonably easy to learn)
[ ] The knot should have a relatively high knotted to unknotted strength ratio - ideally greater than or equal to 70% strength remaining in its knotted form
[ ] The knot must actually be stable and secure
[ ] The knot must look and feel stable & secure(these are tacit factors)
[ ] The tail should ideally be clear of the eye (this is a controversial objective but one I feel should be included as a desirable outcome)
[ ] The knot must perform well in EN 1891 and EN 892 kernmantel rope construction

ABoK #1047 will always be a prominent knot in a climbers/rescuers toolbox. I personally have used #1047 for 20 years with countless numbers of lead falls on a range of rope diameters (all EN 892 certified). At no stage have I died or the knot catastrophically failed. I will readily admit that as ropes have become thinner and lighter over the years, there has been a corresponding degree of difficulty in untying the knot (I weigh 100kg). I have never had a situation where I couldn't untie the knot - but it has taken some considerable effort in some instances. And this was in a warm climate - not a snow and ice environment.

The fact remains that the Yosemite bowline is popular and gaining more popularity every year amongst climbers. My question is; Is there a better way? Is the Yo bowline the best choice? Perhaps its a question with no answer, like how big is the universe. Perhaps I want to build a better mousetrap. What has spurred me on is the concept behind the EBDB and increasing the radius of the nipping loop. This is a great concept - and the Yo/bowline doesn't have this benefit. And one comment I would like to add is that we have been focusing on putting 3 or more rope diameters into the nipping loop - but not much has been said about putting 2 rope diameters through the collar. The yosemite finish does increase the radius of the collar - if curvature (specifically a tight radius) is a factor in rope stress and strain, then anything that increases the radius of bends is surely a good thing? The EBSB with Yosemite finish therefore also acts to increase the radius of the collar. Again, I know that this may be an untested and controversial feature.

I am still leaning toward the EBSB with Yosemite finish... look, I know that by making outright/bold comments as I have just done will immediately draw everyones attention. If I am popping up on your radar screen and I have your attention, then I am another step closer to crossing the finish line (which seems to always be just over the horizon!)...

In relation to the EBDB - I see this knot as a demonstration of engineering par excellence. But, for me, it fails on the tacit features of "looks" and "feels" secure and stable. I also am of the opinion that it may tend to work itself loose after cyclic loading (load on, load off, then load on and load off...ie tension, then no tension, then tension again...repeat the cycle). This might also be more pronounced in stiffer brands of EN 1891 and EN 892 ropes. I would be happier if the tail was tucked somewhere to lock it all together. I should point out that I am speaking in relation to mission critical applications in life support context (eg vertical rescue and climbing). I would have NO hesitation in using the EBDB in any other non mission critical application - eg for use in rigging/lifting with a crane, camping, boating, etc...

The Janus also fails on these points (for me). It doesn't look and feel stable and secure to me. I can also foresee that it may work loose when subjected to cyclic loading.

A paradox is that the standard Yosemite bowline does look and feel stable and secure to me! But it could benefit from having a third rope diameter inside the nipping loop, blah blah blah...

...

Be that as it may, I am still reading through all the posts...

And by the way, I still would like a definitive answer re the EBSB with yosemite finish - has it been published anywhere before? Has it been described or documented in any way?

...

To answer DerekSmith's question re the fall factor of my 1.0m lead fall... There was 10m active rope fed out from the belay device and I had a 1m fall. This equates to a fall factor of 0.1 (three fifths of sweet bugger all). But, it did act to put some stress and strain on my knot. Remember, I weight 100kg. The figure 8 eye knot was very difficult to untie with the joker 9.1mm diameter rope - in that I had to apply some considerable effort to work the knot loose. The EBSB with Yosemite finish was easy to untie - in that I did not have to apply any force or significant effort to loosen the knot.


agent smith

« Last Edit: December 29, 2008, 05:56:54 AM by agent_smith »

Dan_Lehman

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #61 on: December 29, 2008, 06:52:11 AM »
Quote
GRATUITOUSLY COMPLEX ;  TOO CLEVER BY HALF ! !
--especially regarding tying it:  the more tucking you require, the more of a pain in the ass
it is to do, and the fewer people who will do it, and fewer times they do so!
And then, it's not all so effective re security.

Quote
I also don't think it is that complex. I find the janus variant more complex! There are degrees here ...

The EBSB with yosemite finish does require a couple of tucks to finish but this is just conditioning in my view.

First off, the name "EBSB" belies the actual degree of variance with the EBDB;
implicit in the EBDB is an EB(s)B, which is the undoubled-loop/hitch knot,
to which you have added both a further tuck through the "EBinding" AND the Yo.finish.
I call "foul"!

It is more than adding further tucks to an already mind-boggling extension for the masses,
but that tuck cannot be well made--drawn tight, as it should be--without attentive and
difficult working !!
  Yes, your AEBSB (Adulterated) w/Yosemite sparkles involves
a 3rd diameter within the end-binding, but that diameter is the tail and must be added
prior to tightening the wrapping but then the tail is going out and tucked yet again and
there is nothing left to haul the binding tight with, unless you budget just enough bonus
rope ... --which is a waste of material, and might beget a "safety" knot just to remove
the annoyance of a long flapping tail!  --which would OTHERWISE be a ready alert
to the knot having lost some tying and been coming loose:  you remember, that thing
you might see when glancing down just before you lunch for your crux move!

To see this as no more complex than any of the Janus variants is to seriously fail
to assess the knots reasonably.  In the little space that one has between a couple
and a few more wraps, this is a huge difference.

Which brings me to the point of your illustrations (photos):  they are good for seeing
pretty much what is entailed in each knot (again, getting that proper facing prominent
is a help), but they in some cases leave unshown what the knot should look like
DRESSED & SET--which is, afterall, what the belayer should be double-checking
for, not for the slightly intermediate form.

I set the EBDB by:  quickly giving some tug to the whole knot, and barring some gross
imbalance in looseness, I tension the EndBinding, and haul tight the SPart-side eye-leg
(which , were the EBinding not adequately tight, would be in vain--any tensioning
immediately lost back into a loose knot), which puts the clamp  upon the EBinding,
which then gets a final setting, and finally the collar is sized to try to anticipate its
stretch such that it will see the SPart firmly pressing around the knot:  coming sort
of around over the double turns as it flows into them, some pressure put on them
and not all upon the constricted legs of the bight.

And you simply canNOT do this direct, full setting of those knots with the tail tucked
through the EBinding--not easily, not marketably  to a user community resistant
to change and skeptical of the bowline.

-----
For the Janus-ii let's call it--one you got verbally and put into a photo (Fig.32-3)--,
tying flows from the quick-tie's HH/loop-forming maneuvre to selective collaring
that yields a Cowboy/1034.5 Bowline base, and then the end is swung easily
behind the eyelegs to come back  over/around them and back down into the
central nipping HH/loop, making a symmetricly formed (aiding inspection) knot;
setting proceeds much like for a common Bowline with the added hauling tight
of the eye-leg collar--set tighter than the SPart's collar, for a bend in this only
half-loaded part is not a liability, and the eye leg needs to be snug to the nub
to press secure the SPart's turn in the HH.  --same finish to a Dbl.Bowline of
"Cowboy" orientation gets good results.

--------

Btw, re the history of the Janus Bwl attributed to Prohaska, please see
http://charles.hamel.free.fr/Alpine_journal/
and note Wright & Magowan's well prior such knot, which I think differs
only in the passing/crossing of the end with itself on final tuck-exit,
which is a trivial thing.  And THAT is a 3-diameter bowline.

And that is, the knot must appear to be secure. ...  for example, when I momentarily peer down at my rope tie-in
while executing a tricky sequence of moves on a difficult climbing route, I like to see that all is in order - dressed, compact, shape and form, etc.

Un-huh:  and in a stressful quick glance you can see at most whether a seemingly
longer tail is dangling--hardly whether the right tucks/wraps have been made,
which is a pre-climbing check, arguably done jointly with the belayer (who doesn't
want to catch you in the lap!).

Quote
Your first bowline variant has merit DerekSmith,
but I just can't see it being adopted in mission critical life support applications
- for the simple reason that it doesn't look secure! This is ...

... absolute poppycock:  why, it doesn't LOOK secure because it won't even stand still
for a picture, let alone a walk up the wall!!  What in the world are you tying this knot
in that in any way gives the slightest disguise to its considerable INsecurity?  I cannot
let this pass w/o rebuke, for the knot is VERY lacking in security in the climbing rope
I've tied & re-tied it in now several times, completely baffled by its recommendation
and now a seconding.   ???

Quote
As for the Joker rope, I failed to mention that I climb with 'double ropes' - that is 2 x EN 892 category 'half' ropes.

Which is something I've never quite understood, since diagrams of half-rope use show that
many falls can essentially be on JUST a half-rope, the other being unclipped relative to that
particular fall point.  In any case, relevant to this discussion, what IS the tie-in method:  TWO
tie-in eyeknots (so, two strands of rope running through the harness)?  --conceivably, one
rope could be tied into the 2nd and the 2nd alone tied to the harness.  If two strands ... ,
then one wouldn't be wanting to use a twin-eye/redundant-eye eyeknot!

--dl*
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agent_smith

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #62 on: December 29, 2008, 07:58:33 AM »
VER 1.8 is up... still have enough fuel in the gas tank to spur me on...

Dan, I have deleted the last two grotesque variants as I agree with you in that they are not in the same engineering class as the other variants in this paper.

I have had a second go at photographing what I'll tentatively call a cowboy janus variant...hope it looks better this time!

With regard to cinching up and dressing all of the knots - I am trying to strike a balance between obtaining high quality images and still being able to follow/understand the knot geometry. I agree that maybe I should indicate that none of the images are properly cinched up & dressed - they are all generally loosely tied.

... with regard to climbing with double ropes - there are numerous and significant benefits to be had, particularly if you are establishing new long multi-pitch routes in wilderness areas. This subject perhaps is best let for another thread (but then it wouldn't be a knotting topic).

And I am still not hearing definitive argument as to why the for want of a better name EBSB with yosemite finish should NOT be used...

agent smith
« Last Edit: December 29, 2008, 07:59:28 AM by agent_smith »

Dan_Lehman

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #63 on: December 29, 2008, 08:19:02 AM »
Quote
[ ] The knot must look and feel stable & secure(these are tacit factors)
[ ] The tail should ideally be clear of the eye (this is a controversial objective but one I feel should be included as a desirable outcome)
[ ] The knot must perform well in EN 1891 and EN 892 kernmantel rope construction

The first is silly (and how would you expect to test for that?).
The second is without a compelling rationale for a tie-in knot.
And then there's that issue of what a "mantel" is, contrasting with what the rope has.
(But we've been over that previously.  Google has interesting counts on this.)

Quote
The fact remains that the Yosemite bowline is popular ...

A variation is more easily made by bringing the tail across UNDER itself (given the
"front" view), in which case it would bend around 2 rather than 1 diameter; this is also
an easier knot to tie and to tie as a Single Bowline in the Bight.  --something for your
blank pages, maybe.  But with all your going astray, you're still due to figure out at
least one of the various "mirrored" bowlines--ones with the Clove, Cow, or --how to
say-- "split Clove/Cow" bases.  (The "split" cases loose on the easy understanding grounds,
but I do like one of them!)

Quote
but not much has been said about putting 2 rope diameters through the collar. The yosemite finish does increase the radius of the collar
 - if curvature (specifically a tight radius) is a factor in rope stress and strain, then anything that increases the radius of bends is surely a good thing?

But I have addressed this:  that extra material in the collar could simply shift such that the two diameters
aligned to become a 1-diameter bend with the 2nd strand just, so to speak, "standing in the shadow"
of the 1st (recall my point that 3 diameters better approximates a circle).  I think that should push come
to shove, the end will shift out of any helpful compression--though it just occurred to me if in fact it
could possibly provide enough compression on the SPart to give Connally's asserted strength gain
--something I've not seen otherwise documented (and Prohaska claimed brief testing to show his
Janus being stronger).  The collar around the SPart isn't desired to be enlarged--that is no way
a weak point--; it might be beneficial to have an end snugged into it, but not for the purpose of
making the collar bend less.

Quote
I am still leaning toward the EBSB with Yosemite finish...

Yeah, and you thought Derek's 1st had "merit", too.  I'm getting a feel here.
That "EBSB" is DOA in anyonElse's consideration, believe it.

And yet YOU think, quite a surprise, given the post it was in reply to:
Quote
And I am still not hearing definitive argument as to why the ... EBSB with yosemite finish should NOT be used...
So, I'll put the entire sentence (vs. part done before) in bold--to wit:

It is more than adding further tucks to an already mind-boggling extension for the masses,
but that tuck cannot be well made--drawn tight, as it should be--without attentive and
difficult working !!


Now, it does give good grip on the end to resist loosening, but at a price of
tying, setting, and inspecting (and some material).  And in the face of simpler
alternatives that can win acceptance.  (One can take the A_S aspect of the
extra tuck a step further, with slightly different-than-Yosemite wrapping and
tucking and gain a 3rd partial cover to the end.  But one can work much
more happily with Mirrored Bowlines and other variants.)

Quote
... the EBDB ... fails on the tacit features of "looks" and "feels" secure and stable. I also am of the opinion
that it may tend to work itself loose after cyclic loading (load on, load off, then load on and load off.

Maybe you're not setting it adequately?  Is there some reason that this knot might be vulnerable
to cyclic loading loosening?  --can we see some action at a point where relaxed strands will
work something loose?  I don't.

Quote
The Janus also fails on these points (for me). It doesn't look and feel stable and secure to me.
I can also foresee that it may work loose when subjected to cyclic loading.

A paradox is that the standard Yosemite bowline does look and feel stable and secure to me!

"Paradox" is one word one might use for it; others are suggesting themselves.
My shake test (in hand) is better than mere looking; how to get uniformly distributed shaking
for some duration to test a set of knots, that's a quest.

Quote
And by the way, I still would like a definitive answer re the EBSB with yosemite finish
- has it been published anywhere before? Has it been described or documented in any way?

Are you looking for someone who has read everything ever published?
The EBinding and the Yosemite tuck have been described.  Some people, though
not all, can add one plus one and get to two.  (Some can see one plus another
certain one leading to zero, too.)

Quote
But, it did act to put some stress and strain on my knot. Remember, I weigh 100kg.

I'll wager that you can do as much with a pulley, and more easily.
Which will tell you nothing about security & stability, and maybe not much re strength,
unless you know what to look for.

--dl*
====

DerekSmith

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #64 on: December 29, 2008, 12:20:17 PM »
Thanks for all of your considered feedback and critique DerekSmith.

snip...

What concerns me is that your words may be taken as advice since you might be perceived to be an expert on the subject.

snip..

agent smith

Thank you for the reminder AS, you are quite correct, I am not an expert in climbing safety and I certainly am not giving advice by stating what in my considered opinion is the the best course for myself.

However, I would post caution to you. 

You clearly are taken to be an expert and are called upon to give expert testimony and particularly, your project is also clearly intended to be promoted as advice.  Yet you are ever more repeatedly using terms like "It feels Like" or "It gives confidence" or "A desirable trait appears to be".  You seem to be focussing on a solution which 'feels good in your opinion' but you are not developing any factual basis (assuming any exists) for this position, simply propounding and compounding 'likes' and 'feel goods'.  Yet because you are taken to be an expert, your findings will be taken seriously and will not be questioned in detail or understood in context (by climbers or legal people) as they might be by the very focused expertise of the members of this forum.

Expertise is a two edged sword my friend, wield it carefully.

Derek

DerekSmith

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #65 on: December 29, 2008, 01:31:05 PM »
This topic is generating so many sub issues, each warranting a sub thread of their own in order to retain focus on the sub issue within the overall issue.  Sadly, these sub issues are being lost in the rapidly growing volume of replies (I went to sleep and a whole new page has been added).  At times like this one wishes for a forum facility to spawn off sub threads from within the primary thread, but this does not seem to be possible.

Perhaps we should consider making some 'hand made subs' by calling them 'Janus Bowline Sub... etc'

Some subs might be ...

Janus Bowline Sub... Strength
Janus Bowline Sub... Security
Janus Bowline Sub... Aesthetics
Janus Bowline Sub... Grail definition / requirements


I particularly have issues with the Strength aspect which I would like to develop in more detail, so unless you are in complete disagreement, I will post them into a new subthread.

Derek
« Last Edit: December 29, 2008, 01:33:52 PM by DerekSmith »

DerekSmith

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #66 on: December 29, 2008, 02:29:01 PM »
Thanks for all of your considered feedback and critique DerekSmith.

As for the Joker rope, I failed to mention that I climb with 'double ropes' - that is 2 x EN 892 category 'half' ropes. When the joker rope was released to public, I immediately adopted it as one of my double ropes. I try to clip the joker rope into protection in crux sections of a route - so in the event of a fall, it will be the joker 9.1mm rope that takes the initial impact. My other rope is a standard 9.0mm diameter 'half' rope.... double ropes offer many advantages over single rope systems but I wont go into detail here as it is off-topic...

agent smith

Absolute off topic here, so I will make it short.

You stated that you climb on double ropes, one of which is the Joker - i.e. they are different ropes.

From memory, normal dynamic ropes have a ca 8% - 10% extension factor, but when I looked at the Joker spec. it stated 37% extension (AKA bungee cord).

Isn't this a bit like mixing radial and cross ply tyres on the same axle?

When you fall, your second will have both ropes through the belay and will check both at the same time, so your falling force will go roughly equally (protection permitting) into both ropes.  But if one of those ropes has a high modulus of elasticity (ME) it will extend without taking an equal share of the load - essentially, the lions share of the load will go into the stiffer of the two ropes.

Imagine the analogy of climbing on one static and one dynamic rope.  As you fall, all the force would be taken by the static rope and either your back would break or your protection would be smashed while the dynamic rope was only starting to think about taking any load.

Have I misunderstood the technical spec for the Joker or does your other line have a matching ME?

Derek

Dan_Lehman

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #67 on: December 29, 2008, 09:48:46 PM »
You stated that you climb on double ropes, one of which is the Joker - i.e. they are different ropes.
From memory, normal dynamic ropes have a ca 8% - 10% extension factor, but when I looked at the Joker spec. it stated 37% extension (AKA bungee cord).
Isn't this a bit like mixing radial and cross ply tyres on the same axle?

When you fall, your second will have both ropes through the belay and will check
both at the same time, so your falling force will go roughly equally (protection permitting)
into both ropes.  But if one of those ropes has a high modulus of elasticity (ME) it will
extend without taking an equal share of the load - essentially, the lions share of the load
will go into the stiffer of the two ropes.
...
Have I misunderstood the technical spec for the Joker or does your other line have a matching ME?

Yes, you've grossly misunderstood:  the UIAA limit on extension on the drop test is 40%; if you'd
looked at some other ropes you'd seen a range e.g. from 29% to 35%.  THIS IS FOR THE DROP,
and IIRC for some subsequent drops, depending on the richness of the information given.
Your recalled figures make sense only for "static elongation"--stretch from bearing "body weight",
again using 80kg for that.  What is sadly often omitted from 6,7, & 8mm accessory cord ropes is
just such information, which is relevant to abseiling, which is often done using a climbing rope
joined to a thin haul line--and I've seen it presumed that the latter will stretch more, being
weaker, but being non-dynamic I'm not so sure that this is true--but a sort of *simulated*
stretch can obtain via the thin rope's slipping through the belay device more easily.

Also, in the use of " H A L F "  ropes--in contrast to using " T W I N " ropes (and "Joker" name
is won by qualifying for both of these AND qua SINGLE rope to boot!)--, it should often be
the case that only one rope bears the fall (which aspect has really puzzled me), as e.g. the
paradigm of use is where a route zig-zags up a wall, and each rope stays to its respective
left/right side, and so on any given fall, one rope is likely fetching up on the high anchor
point while the other's latest/highest anchor is well lower & away; I guess, the harder
the fall and longer the stretch, the more the 2nd rope will get to pitch in.  YMMV per climb.
TWIN ropes are touted as being best for durability and resistance to cutting (qua twin),
as well as being their own 2nd-rope abseil partner.

--dl*
====


agent_smith

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #68 on: December 29, 2008, 11:00:53 PM »
Again, I wish to personally express my gratitude for all the considered responses in relation to the bowlines... thank you.

Another point i wish to make is that I am trying not to direct anything as a personal attack against anyone on this forum. For example, I respect DerekSmith's bowline variant with the tuck under and across the bight. I used the word 'merit' out of respect for the man. Depending on application (perhaps in non mission critical applications involving human life support) perhaps it does have merit. I am trying to be respectful at all times...DerekSmith does have expertise in knotting matters...so I listen very carefully when he speaks/writes in this forum.

The same can be said of Dan Lehman. His technical genius at times overwhelms me. I feel that I am merely a member of parliament sitting and debating with eminent politicians of considerable power and stature...so I listen and take it all in and try to add my opinion here and there.

On the subject of the clip-in method of attaching a climbing rope to a persons harness - I have been involved in investigating several horrific cases where children have had their lives virtually destroyed - and I guess it pulls some of my heart strings. I do get emotional on this subject...sorry.

I will say that in some climbing contexts - eg indoor climbing facilities and fixed outdoor challenge ropes courses, a clip-in method can work - provided staff had accurate and well directed training and assessment. There are certain conditions that MUST be met in order to reduce the risk levels down to what I'll refer to as an 'acceptable' level (in many Australian legal jurisdictions, the phrase 'acceptable risk' appears from time to time).

In the State of New South Wales (where Sydney is located and the Opera house and all that..) a simple clip-in method has effectively been eliminated by court precedent. So what some climbing gym operators have done is to use a combination system using both a carabiner clip-in together with knot tie -in. This is now back on the subject of knots.

The clip-in + tie-in combination offers many advantages and fewer disadvantages. The State does not specify which knot is required - that is left to the owner of the workplace (or climbing gym proprietor). I have seen ABoK #1047 (figure 8 eye knot re-threaded) and ABoK #1053 (Butterfly knot). But I have yet to see ABoK #1010 (Bowline) or its derivatives.

Personally, I prefer the Butterfly since its geometry allows for tri-axial loading.

DerekSmith, I sense in your replies that you are firing a shot across my bow. I do not mean to offend - but I have an opinion (like you do). In your expert hands, you have the depth and breadth of knowledge and skill to overcome any inherent residual risk when using a clip-in method to your climbing harness. I meant to say that others in this forum may not have your climbing AND knotting skill. As I indicated, provided certain actions are taken to reduce risk, the clip-in method can and does work in top rope climbing applications (I would never recommend the method in LEAD climbing applications) and on fixed challenge ropes courses. Human error is a factor and this is what occurred in the accident involving the schoolboy who sustained horrific injuries. The carabiner was a locking design with a captive pin. I'm happy to email you the (edited) report.

Other than that, I am still actively searching for the ultimate bowline and when I use words like 'leaning toward' or 'prefer' it means just that. It is not an outright declaration of affirmation. Its just that the evidence collected thus far - makes me lean this way or that. It doesn't mean I have hit the jackpot.

As more new technical data is gathered (from experts such as Dan and DerekSmith and Co.), I might lean another way!

So far, I have stated that the EBDB is a demonstration of engineering excellence. But, I tried to point out tacit criteria (tacit is something which cannot be measured by ordinary means) plays a role for me. And I knew that this would land me in hot water. I cannot find any better words in the English dictionary to explain myself... for me, there are certain aspects of evidence and criteria which can only be explained by using the word tacit.

I can't foresee that I would use the EBDB as a tie-in method for lead climbing.. but thats only MY reaction and it may well be based on flawed logic.

I am still trying to understand WHY the Yosemite Bowline (YoBowl) has become so popular... perhaps there are tacit factors at play which I do not yet understand. For example, if a YoBowl can gain widespread acceptance, why can't an EBDB? Why do I not see the EBDB in widespread use in climbing and rescue communities? Perhaps if I could answer that question, I could find my holy grail knot...

agent smith


agent_smith

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #69 on: December 30, 2008, 01:03:02 AM »
Just found this link:

http://www.dickeyfamilyresearch.com/knot_pics/bowline_list.htm

and this related link at same site:

http://www.dickeyfamilyresearch.com/knot_pics/bowline_pics_0.htm

and of course there is always one of my favourite sites (which is known to all IGKT members): http://www.layhands.com/Knots/Knots_DoubleLoops.htm

While you've got time, have a quick look at this site: http://members.tripod.com/johnnycl/CLIMBINGKNOTS.htm

Note the 4th image down (described as a "double bowline follow-through"). It uses a yosemite finish and makes a claim that 'many sport climbers prefer this knot'). Interesting comment!

And I also found this site - http://www.globalsecurity.org/military/library/policy/army/fm/3-97-61/ch4.htm  while not directly Bowline related - its got some knot terminology and other information.

Will sift through all the Bowline variations therein...

The hunt goes on...



agent smith
« Last Edit: December 30, 2008, 01:22:20 AM by agent_smith »

Dan_Lehman

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #70 on: December 30, 2008, 01:17:28 AM »
I respect DerekSmith's bowline variant with the tuck under and across the bight. I used the word 'merit' out of respect for the man. Depending on application (perhaps in non mission critical applications involving human life support) perhaps it does have merit.
..DerekSmith does have expertise in knotting matters...so I listen very carefully when he speaks/writes in this forum.

I don't care if the angel Gabriel came down and blew his horn over it,
you need to call a spade a spade, and be willing to put to test the assertion.
You have the material(s) to do that.  And that lame tuck-through-collar/SPart-space
Bowline is an obvious dud in climbing rope; and, quite frankly, with little to recommend
it for anything, given the NUMEROUS better alternatives!  Didn't you get the story
about the king who was naked?  (Or the Bush administration who were lying?)
And then the wild conjecture about the Bowline vs. Sheet Bend,
in the face of ages of evidence to the contrary (in testing & usage),
and i.p. cited test data exactly relevant to the OP given in the discussion?

Quote
On the subject of the clip-in method of attaching a climbing rope to a persons harness - I have been involved in investigating several horrific cases where children have had their lives virtually destroyed - and I guess it pulls some of my heart strings. I do get emotional on this subject...sorry.

I had left this alone, but it strikes me as most dubious to find a failure in
a 'biner--ANYway loaded--with the falls that should be occurring in a climbing
gym, which I think was the scenario--esp. of young (read "light") children!?
--at their weakest, most 'biners should be amply strong enough.

You've not responded about how a climber with Half (or Twin, for that matter)
ropes ties in:  what exactly is done (in the latter case, which end (bight/ends)
has the climber?) ?!  (As remarked above, I could SEE a Fig.8 eyeknot as one
end's attachment, as usual; and then the 2nd rope is tied into this Fig.8,
as though making a bend to join ropes.)

Quote
The clip-in + tie-in combination

... begs the question:  why ... ?  Is it that the facility has pre-tied all ropes
to the 'biner, and is sure of their security, and so sees the clip as a back-up
to possible mis-tied knots (and the latter to some back-up to 'biner failure)?!

Quote
Personally, I prefer the Butterfly since its geometry allows for tri-axial loading.

Ha!  Nice rumor, but hard fact ... ?  Interestingly, in data published in the CMC Rope
Rescue Manual, the through-loading difference between the Butterfly & Fig.8 was
small (one can see ranges for the B. from lousy to super (Richards's, e.g., are good);
I have to wonder at the exact geometry (a question others ignore)).

Quote
Other than that, I am still actively searching for the ultimate bowline

Here's another, which seems more snug in set form than some,
and is no more cumbersome.  From the Common Bowline (#1010) start,
as you present it, pg.2 fig.1,
take the tail right over the Spart-eye leg,
and back around it leftwards under BOTH eye legs,
and up around the left-/bight-side eye leg
to be tucked down BETWEEN END & HITCH CROSSING PARTS (Derek's red zone);
   - -  you have now formed a loop around the eye legs - -
and finish by tucking the tail down through the just formed loop,
parallel to the eye legs, working this loop as snug as possible.

.:.  This version gives a GOOD curvature to the SPart, and good friction against
various parts to help keep the knot from loosening and from loosening much
(even if it loosens some).

Quote
I can't foresee that I would use the EBDB as a tie-in method for lead climbing..
but that's only MY reaction and it may well be based on flawed logic.

Well, yes, the Janus'd Cowboy Bwl is simpler & quicker, I agree.

Quote
I am still trying to understand WHY the Yosemite Bowline (YoBowl) has become so popular

Monkey see, monkey do.  If the knot gets the press, it can get more
in a nothing-succeeds-like-success fashion.  Why was the "cordelette"
anchor structure so popular?  It had some popular, big-name advocates
(viz., John Long), and as such things typically don't get pushed to the
extremes that might reveal deficiencies, who really knows ... ?  To me,
and to some others, it seemed obvious that in many cases one would
be loading a single anchor point rather than distributing force to three;
but only upon doing testing for the 2nd edition of his Climbing Anchors
book did John do testing that documented this shortcoming.  (Heck, I even
had a special cordelette powerpoint knot published in Outdoor Knots,
which, btw, was a bowline of sorts.)  So, the YoBowl gets known and
insofar as there are non-Fig.8-eyeknot tyers, it gets some popularity.
Authors do a lot of copying, too--uncritically--, which is vastly easier
than researhc.  E.g., the --as GBudworth-titled article leads me to call it--
Wot?knot was repeatedly published and botched or modified over a
century by many authors, and none of the variations made a decent
knot--and some were outright comical--, but if one were to measure
sucess by publication, the Wot?knot succeeded for much longer than
it should have (it shouldn't have received any press).

Quote
Will sift through all the Bowline variations therein...

That's a very lame sight, geesh.

You are "still searching", but I've yet to see your attempt at the Mirrored
Bowlines.  How hard of a search is this?  Take the Cow /Girth Hitch as
a base; do the bowline maneuvreing with the tail on both sides, in the
fashion of the slow-tie method ("rabbit round the tree"); this is child's
play, and I'm impressed that the Search for the Holy Bowline hasn't
managed it yet (a bowline with two rabbit holes, no less!).  Alice in
Wonderland, it might put a Cheshire Cat smile in your spirit!  This is
a loose-looking knot (various versions) w/good resistance to untying;
might have a bit of shock absorption, to boot. (AND it can give Derek
TWO GeeWhizSpots to color!)

--dl*
====

agent_smith

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #71 on: December 30, 2008, 02:23:21 AM »
Thanks for this,

I don't have your depth and breadth of knowledge and skill Dan - and it takes me a while to understand the geometry of your creations...but I am a reasonably fast learner.


Quote
You are "still searching", but I've yet to see your attempt at the Mirrored
Bowlines.  How hard of a search is this?  Take the Cow /Girth Hitch as
a base; do the bowline maneuvreing with the tail on both sides, in the
fashion of the slow-tie method ("rabbit round the tree"); this is child's
play, and I'm impressed that the Search for the Holy Bowline hasn't
managed it yet (a bowline with two rabbit holes, no less!).  Alice in
Wonderland, it might put a Cheshire Cat smile in your spirit!  This is
a loose-looking knot (various versions) w/good resistance to untying;
might have a bit of shock absorption, to boot. (AND it can give Derek
TWO GeeWhizSpots to color!)

Attempting to tie and photograph this variant for you now...

Got it - I think. Wow, another example of your engineering genius! I just hope that I don't make a fool of myself and post the wrong damn image!

Dan, please advise if I am on the right track.


Respectfully,

agent smith

Dan_Lehman

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #72 on: December 30, 2008, 03:35:45 AM »
p. 4, Fig.8 (no, not that "Fig.8"--a real figure ) Yosemite bowline variant?

This page is currently blank.  A good candidate for a YoBowl variant is the #1010 Bowline
with an Overhand-shaped vs. Fig.8-shaped (YoBowl) extension.  Which is as follows:
reverse the 1st crossing of the bight's end (the tail) over the bight's other leg--i.e., make
the tail cross UNDER it (between it and loop);
and then--presto--tuck it out through the collar, YoBowl-like, ta-da!
We might call this a Single Bowline on the Bight; it (and the YoBowl, for that matter)
can be TIB (Tied Inthe Bight).  Note that in this variant, the Overhand's finish entails
a 2-diameter wrap, vice the YoBowl's 1-dia. wrap.

----------
And as long as the collar is getting this gratuitous traffic, I should note that the
collar could be made with a round turn through which the Yo'd tail would be
squeezed for that tacit feel-good quality.  (And it kinda resembles a wrong-way
Dbl. Bwl.)  ((And this version + round-turn'd-collar is still TIB.))


Quote
Dan, please advise if I am on the right track.

I sense a Yosemite finish aching to come out.

 :D

agent_smith

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #73 on: December 30, 2008, 06:10:19 AM »
VER 1.9 is uploaded...

Same link: www.paci.com.au/IGKT/Bowlines.pdf

I have added what I am tentatively calling a girthed bowline (see figures 34 & 35). I think this is what Dan Lehman was describing... I noted that the geometry did not provide for 3 rope diameters placed inside the nipping loop...so I added figures 36 & 37 in a hasty attempt to provide this benefit... which may be totally screwing up Dan Lehman's creation! Anyhow, I'm sure I'll receive feedback in close to light speed...

My initial reaction was excitement over the girthed bowline but this is now tempered with thoughts that it could still be improved either by adding a third rope diameter into the nipping loop and/or a combination of locking the tail in some fashion (perhaps in some type of Yo/Bowl geometry..!).

I have also tried to incorporate DerekSmith's knot terminology to better describe a knots anatomy. Hope this is an improvement! Am seeking guidance here...


Quote
A good candidate for a YoBowl variant is the #1010 Bowline
with an Overhand-shaped vs. Fig.8-shaped (YoBowl) extension.  Which is as follows:
reverse the 1st crossing of the bight's end (the tail) over the bight's other leg--i.e., make
the tail cross UNDER it (between it and loop);
and then--presto--tuck it out through the collar, YoBowl-like, ta-da!
We might call this a Single Bowline on the Bight; it (and the YoBowl, for that matter)
can be TIB (Tied Inthe Bight).  Note that in this variant, the Overhand's finish entails
a 2-diameter wrap, vice the YoBowl's 1-dia. wrap.

No comprendi...trying to tie this but getting confused.. I am starting from #1010 via its front orientation right? Not exactly sure what to do with the tail...

agent smith
« Last Edit: December 30, 2008, 07:17:45 AM by agent_smith »

Dan_Lehman

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #74 on: December 30, 2008, 08:21:32 AM »
VER 1.9 is uploaded...
Faster than a speeding bullet!

Quote
I have added what I am tentatively calling a girthed bowline (see figures 34 & 35).
I think this is what Dan Lehman was describing... Anyhow, I'm sure I'll receive feedback in close to light speed...

Turnabout is fair play!
"Mirrored Bowlines" was the given name (you didn't need to search for that),
and heed the words:

1) "Take the Cow /Girth Hitch as a base;
CHECK, YOU GOT THIS.  (I will note that in the COW base, unlike the CLOVE, one can reverse-orient ends.)

2) "do the bowline maneuvreing with the tail on both sides,"
BUT YOU DID >>>NOT<<< do this.  We see thus only the one, usual collar.   b o r i n g  .  --a Water Bowline-like knot.
You need this "on both sides":  recall the moniker, "MIRRORED"--that means as though
a mirror was the dividing plane across (perpendicular to) the mid-section of the nub,
bisecting the Cow/Girth hitch base.  The collars *reflect* each other (each around an
end of the Cow H.).  I guess we could say it's a Janus-ing of a Clove/Cow/... base, then!?
And the reflection naturally provides the third diameter through the loops
(which strictly speaking breaks pure *reflection*).

And I'll remark:  if you back the end out of the 2nd loop (2nd half of Cow),
and then haul hard that loop to capsize/straighten it,
you'll put the loop into the other eye leg; you can then continue with the
tucking & collaring from here.  In some orientation of this added-on/reflected nipping loop,
you can get a good jamming on setting the knot (re security, not serious jam-cannot-be-loosened);
and with the loops now one in each leg of the eye, I suspect there should be some
better **spring** in the structure to absorb shock (though still ONE of the trio of
diameters running through the core is purely straight, without any hope of some
*mechanical stretching*).
Put another way re this splitting the loops, it's probably easiest (re torsion, e.g.) to start
with a common bowline, then in bringing the tail back to the nub, first make the desired
HH/loop around the 1st/SPart-side eye leg, then reeve up through original loop,
collar SPart, back through both loops now, collar end-side/bight-side eye leg,
and back ("up", as AS orients knots; "away", for a climber tying in) through the loops.
Position of the trio of diameters matters only for the 1st-formed, heavily loaded loop,
for strength.

-----------

It should be seen in this long-winded exploration of bowline variants that various mechanisms,
rope component structures, can be used in all sorts of combinations:  e.g., the extra turn in the
common Dbl.Bowline can be combined with the "EBinding" of (for the EBDB) or with the
eye-leg collaring of the Janus Bowlines or with either of the Yosemite-like tuckings; so, too,
with the Clove or Cow or Rolling Hitch base; and then of those bases, as I just noted,
the turns can be split between parts rather than in the single/same strand).  In short,
there are sufficient components here to project into a great many knots.
(And a Janus'd Dbl. Bwl. looks much better than the Yo'd variant!  The extra turn,
you see, directly affects the Janus's tucking the end back through the loop(s),
but not the Yo's sending the end over them through the collar.  .:.  Invest where
your investment gains interest!

And this great variety is much a doublEdged sword, though for many its sharper edge
will be a dangerous one of confusion in instruction and "KISS"--in keeping the user's
knot repertoire to a manageable and commonly understood set.
  --great ambivalence--

--dl*
====

 

anything