Author Topic: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes  (Read 153933 times)

[Inkanyezi] gone

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #120 on: November 07, 2009, 10:23:06 AM »
Eskimo Bowline simply is a name for a knot; we can leave the discussion of anthropology somewhere else. No matter who ties it, it is an eskimo bowline, which evidently may be tied in four different ways, The Tugboat Bowline, Flying Bowline or Angler's Loop ABoK #1017, also is just a name for a knot, which tells those that knows it by such a name which knot we're talking about. Whether it was ever used on a tugboat or by an angler is irrelevant. In verbal communication, it helps to have common ground in nomenclature.

I'm sorry to say that from there, I lost you completely, I don't have the slightest idea of what constitutes a dropper loop, and I cannot decipher the meaning of "form a loop and twist it around the overlap" once or twice or in what sense.

That's why pictures often are so helpful. Ashley designed his great book around pictures, as they indeed sometimes say more than a thousand words. Words without pictures often cannot be reliably interpreted. So much verbosity, so little information conveyed.

It should also (firsthand)  be considered, that all these variations violate an important prerequisite; namely ease of remembering and tying correctly without risk of erroneously introducing a fatal error. It's the KISS principle that we must adhere to. If we are to teach a knot to which we will trust lives, our own and other's, then it is important not only that the intended knot is secure, but also that we indeed tie the correct one and do not mistie it, forming some other contraption that may not be secure.  

What we are looking for is not a smorgosbord of knots that may be formed out of a simple start, but one simple knot that may be securely tied every time, and that will serve the purpose under demanding conditions, including flogging, ring loading and extreme load. The Janus Bowline http://i3.tinypic.com/wjwh1t.jpg may be an answer to this, and my preferred knot would be the Wave Loop, which is built upon the Carrick Bend pattern http://igkt.net/sm/index.php?topic=434.msg3568#msg3568. Testing should be undertaken with both of those. It should also be considered that mistying the Wave Loop is possible, making the first turn in the standing part (as in the bowline) instead of in the leg of the eye, making another form of the Carrick, a different knot, which also has to be tested. Possibly both will be secure and strong. If so, one may consider teaching this second way, as its resemblance with the start of the bowline will make it easier to memorize. This latter variation might also be drawn up by ring-loading, making another different knot which will also have to be tested in the same way. This last one is probably the easiest to tie in a consistent way.
« Last Edit: November 07, 2009, 02:40:10 PM by Inkanyezi »
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[Inkanyezi] gone

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #121 on: November 07, 2009, 03:41:42 PM »
I hoped you should not return to the erroneous conception of eskimo/Inuit. There are various populations of Alaska, Northern Canada and Greenland, and the term eskimo (raw meat eater) might be frowned at by all of them, just as a French person might be intimidated by "frog-eater". Several of those might not object to be called inuit, as it just means people, but in that sense I am just as much inuit as they are. If they would want to be identified by their tribe, it would perhaps be Yupik, Inupiat, Aleut, Athabaskan, Tlingit, Haida or Tsimshian. Of course I would not call a Yupik eskimo, but by his name, which might be George. That discussion surely is anthropologic. But referring to the Eskimo Bowline, it is only a name of a knot, nothing else, and there is no reason for anyone to feel offended. My grandma would also not be offended because a certain knot is called the granny. And I recognize only one human race, regardless of skin colour. So I am not calling a Yupik neither eskimo nor inuit, but I call the knot commonly known as Eskimo Bowline so, because then people reading it might understand which knot it is, and the knot would not feel offended. I would not suggest changing the name of the knot for reasons of political correctness.

But the subject at hand is that of a secure loop for rescue work. That loop must be reasonably simple to tie, withstand any possible kind of offset loading and also be rather easy to untie. Moreover, it shall not be prone to errors in tying or drawing up, and if there are different ways of doing it, they must all be safe. i think the best would be to start testing those knots that might work for the subject at hand; the proposed Janus Bowline and maybe the Wave Loop.
« Last Edit: November 07, 2009, 07:15:34 PM by Inkanyezi »
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roo

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #122 on: November 07, 2009, 07:44:32 PM »
 
.  But the Zeppelin loop, a knot that is topologically identical with the Zeppelin loop, is violating the KISS principle, because its tying method is so complex, prone to many errors, and difficult to memorize. So captain Rosendahl, who used the Zeppelin bend was clever, and the next guy who used the Zeppelin loop was stupid ! :) What we have here is two almost identical knots, the one obeying the KISS principle and the other not.

I don't think it's "so complex".  Overhand Knot.  Follow Down.  Follow Up.  It's pretty simple if it's practiced.  Most knots need some practice to master.

http://notableknotindex.webs.com/zeppelinloop.html
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[Inkanyezi] gone

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #123 on: November 07, 2009, 08:00:14 PM »
Xarax, maybe you missed that I don't call anyone eskimo, just as little as I would use the derogatory term "frog" for someone from France.

I did try your way of tying a bowline, and a double twist delivers the bowline proper, left- or right-handed depending on which way it is twisted. That knot already has been ruled out, because it is regarded not safe enough. With another twist, it becomes a different knot with double collars and the "working end" making a second turn around the nipping turn of the bowline. It's quite as easily done while tying the bowline in the ordinary way, and it is not very far from the Janus Bowline shown here. Easily tied, yes, and I have tried that extra turn before for further securing a bowline. Whether it is safer than the Janus Bowline has to be tested. I have doubts about its resistance to ring-loading.

All of these of course are worth trying.

The objection to all these knots might be the ease of checking what one has done. How do I know what knot would result from certain actions. In that way, the bowline with either an extra turn added or an extra collar on one leg has a clear advantage, because knowing the bowline, one would know how to make either the Janus Bowline or the one with just one round turn where the end comes back once more through the HH/TurNip.

The variations of the Wave Loop are a bit more difficult to evaluate, but for someone that knows the Carrick Bend well, less so. However, doing them as a pattern, will give consistent results, while the "drop-loop" method will not give the same result each time unless you always do the same number of twists in the same direction.
« Last Edit: November 07, 2009, 08:13:03 PM by Inkanyezi »
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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #124 on: November 09, 2009, 06:58:52 AM »
If a knot like the Zeppelin loop may be considered; i.e. a two step operation, then perhaps some other well known knot might also be considered for the ease of tying and checking. The latter is not unimportant. After dressing the knot, anyone in a team should be competent to check the knot. That might outrule the drop loop variants, because their topology is too complicated even for an expert to know what has actually been tied.

If we are not bound by restrictions on physical size of the knot, the simplest one that I could think of that includes two well known knots done in two step operation would be an eye tied in the bight, to which the end is attached with a double becket hitch. The knot would allow easy inspection, and it would resist offset loading and be fairly easy to untie. For example a Butterfly Loop formed with a conveniently long end that can be thrown around the object that it should attach to, and then the end joined to the Butterfly with a double becket hitch, which I think would be safe enough to use and allow for easy inspection. The Butterfly should be known to all mountaneers, and the double becket hitch is a straight-forward thing easily inspected with little risk of mistying. One advantage over the Zeppelin Loop is that the Butterfly may be tied in the bight at any position along the rope. One may even tie more than one butterfly and leave in place if the rope is relocated frequently, to allow for different size loops.
« Last Edit: November 10, 2009, 12:35:43 PM by Inkanyezi »
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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #125 on: November 09, 2009, 02:42:03 PM »
Trust should not be taken too far. Easy inspection of a knot is a boon, and I would appreciate if my partner took a look at my knot and told me whether he had any doubts about it, before putting my life at stake. So I still think that anyone that might use a rope should also be able to inspect the knot and its anchorage. If I tie one for myself and go down, I have only myself to blame, but sometimes more than one person will descend on the same rope. They should all be able to inspect the knot before descending. If the knot is doubtful, it would have to be retied. A Butterfly is easily inspected, and a Becket Hitch as well. It even has the advantage of being easy to open and relocate, without undoing the whole structure. And importantly, it includes two well known elements that should already be in anyone's toolbox. The cue is that we already know it, nothing new has to be learned, just a somewhat different practice with two objects that are already available.
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DerekSmith

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #126 on: November 10, 2009, 10:35:00 AM »
If a knot like the Zeppelin loop may be considered; i.e. a two step operation, then perhaps some other well known knot might also be considered for the ease of tying and checking. The latter is not unimportant. After dressing the knot, anyone in a team should be competent to check the knot. That might outrule the drop loop variants, because their topology is too complicated even for an expert to know what has actually been tied.

If we are not bound by restrictions on physical size of the knot, the simplest one that I could think of that includes two well known knots done in two step operation would be an eye tied in the bight, to which the end is attached with a double becket hitch. The knot would allow easy inspection, and it would resist offset loading and be fairly easy to untie. For example a Butterfly Loop formed with a conveniently long end that can be thrown around the object that it should attach to, and then the end joined to the Butterfly with a double becket hitch, which I think would be safe enough to use and allow for easy inspection. The Butterfly should be known to all mountaineers, and the double becket hitch is a straight-forward thing easily inspected with little risk of mistying. One advantage over the Zeppelin Loop is that the Butterfly may be tied in the bight at any position along the rope. One may even tie more than one butterfly and leave in place if the rope is relocated frequently, to allow for different size loops.


While we all "consciously or unconsciously" add further simple knots to a basic one in order to add security, the quiet act of realising the principle of compounding simple knots to contribute the component for which they are each exceptional, while each compensates for the weaknesses of the others, coupled with the deliberate announcement of this idea - is nothing short of pure genius and for me, is one of life's very occasional 'EUREKA' moments.


Our intuition to take an already 'goodish' knot and further complicte or compound it to reduce its weaknesses, is turned completely on its head - instead we start with a simple knot which is particularly good at perhaps only one aspect of what we want the final assembly to achieve (i.e. ring loading), then finish the knot with an equally simple knot yet ideal for a totally different function.  It is said that 'simple things please simple minds' - I then must have the simplest mind going, because this Oh-so simple concept is giving me goosebumps over its potential.

Props to you Inkanyezi - you are a genius.  Perhaps I could coin The Inkanyezi Principle - 'Why use one complex knot when two simple knots can do the job better'

Now we can think about divorcing the various functions we have previously attempted to design into a single knot, perhaps now we can start asking questions like-
What is the simplest way of forming an inline loop that has the least impact on strength reduction?  We want to tie a loop which is :-  Strong, Resistant to ring loading, Secure, Simple, Easy to untie - a big ask to get all of those into a single knot.

Now we can think in terms of taking out security and concentrate on the rest, then add the security as a second simple easy to untie knot - such opportunities abound...

Derek

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #127 on: November 10, 2009, 07:20:08 PM »
Mine is a Taurean, and I have already found her (multi functional? I'll say, she is writing a shop for a web site at the moment...).

"a problem that is not yet solved, I believe, and possibly it will never be solved, isn't it that so ?"

Once you have a problem in perspective and can see a way forward, then solutions (if they exist) can be found - isn't that so?

Derek

roo

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #128 on: November 10, 2009, 07:36:44 PM »

If we are not bound by restrictions on physical size of the knot, the simplest one that I could think of that includes two well known knots done in two step operation would be an eye tied in the bight, to which the end is attached with a double becket hitch. The knot would allow easy inspection, and it would resist offset loading and be fairly easy to untie. For example a Butterfly Loop formed with a conveniently long end that can be thrown around the object that it should attach to, and then the end joined to the Butterfly with a double becket hitch, which I think would be safe enough to use and allow for easy inspection. The Butterfly should be known to all mountaneers, and the double becket hitch is a straight-forward thing easily inspected with little risk of mistying. One advantage over the Zeppelin Loop is that the Butterfly may be tied in the bight at any position along the rope. One may even tie more than one butterfly and leave in place if the rope is relocated frequently, to allow for different size loops.


A double becket isn't terribly secure.  Then beside using two knots, the amount of rope used is going to make adjusting loop size, position, and excess a chore.

As far as "any position along the rope", aren't we talking about end loops?
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Dan_Lehman

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #129 on: November 10, 2009, 09:26:18 PM »
Somewhere I think I posted the attached images in this forum,
but Search doesn't grab attachment labels and I'm not up for
more work re that; besides, it will help to put them in place for
this thread.

There is some aspect of the problematic concept/definition of knot
in these discussions:  it would help here if instead of looking to what
some general geometric structure purportedly does --how it
behaves, in general-- that one spoke/thought of How should
this material be knotted?
   For in many instance previously,
and now w/Xarax's here-proposed "bowline" complexity, I find the
advocated knotting of particular materials absurd -- and must believe
that those structures wouldn't have been proposed had the relevant
material been employed (vice the thin, flexible stuff shown)!

We are here talking about knotting typical nylon (also PES) kernmantle
ropes
as are used (and have been used for years) in rockclimbing,
caving, SAR, & --more newly-- canyoneering.  Although there is some
reason to be chary of recent additions to such cordage --the sometimes
firmer, HMPE-/aramid-cored cords & ropes (canyoneering!), and maybe
also the polyester (PES) ropes.  These ropes range from highly elastic
to highly inelastic; from slick & smooth-surfaced to less smooth (i.e.,
worn by use, sometimes to fuzziness) & less slick.  In most cases,
they tend to be fairly firm, though here too have a range from
those whose cross section flattens somewhat at bends to those
so packed with core strength and snug mantle that they hold
a round cross section and bend only grudgingly.

As Roo noted, the Sheet bend is not all so secure, and esp. not
so in some kernmantle ropes.  (Paradoxically, I think that one of
the ropes tested by Dave Richards was less secure in this than in
the single form!)  It is not secure-when-slack (Richards shows
that it can slip at high loads).  And as one of if not the main
use for the subject eye knot is tying to a harness, there one
will typically want a small eye, close knot; the knot-within-eye
scheme thus cannot meet this need.

The End-Bound Double Bowline which is shown in the TinyURL'd
sketches Inkanyezi noted seems amply secure in the cordage domain
of interest here.  Surprisingly --IMO--, it was not secure in a firm,
soft-laid, slick polypropylene (monofilament) cord; whereas looser
knots could hold their (loose) form better.
But for simplicity and use of extant knowledge (well, this is a bit
debatable as to how "extant" it is) --i.e., the Bowline base--, the
simple wrap-&-tuck with the end used for the various "Janus"
bowlines seems a good, simple solution.  It remains to be seen
what help a 3rd diameter of material in the main, nipping loop
is re strength --early test results from Agent_Smith suggest it's little--,
but strength is in any case adequate; security is key, and ease of
untying.

So, I'll show what I now regard as a preferable version on the "Janus"
theme --a moniker of my choice to connote the symmetry of the knot--,
as well as one going a bit more complex, being a sort of Water Bowline
(which has been seen to hold in super-slick HMPE 12-strand rope).
This latter knot can be rather loose and yet get no looser, which
perhaps will have some benefit for those "sport climbers" who take
repeated falls in working out some "problem", for which the ability
of the knot to shed tension --to relax somewhat-- could help
(but regard:  could lead to abrasion/heat damage?).  This latter
knot sure looks "sloppy", but climbers aren't tying knots as art,
but to do a job.

These are both PET (post-eye(formed) tiable) knots, unlike the
standard eye knot, the Fig.8, which must see a Fig.8 tied in the
S.Part prior to completing the knot -- an awkardness in some
situations (but not so much for tying into a harness).

--dl*
====

Note that this "Janus" Bowline is based on what Ashley called
"Left-handed"; this resists ring-loading.

The 2nd knot I call a "Mirrored Bowline", as it can be regarded as
a bowline with a mirror placed across the eye legs perpendicular
to the axis of tension (to the rope), showing like knotting on
both sides.  This can be pretty loose (but keep the Cow Hitch
base reasonably snug), and yet resist shaking to further loosen
-- so many parts abutting and inhibiting turn expansion & material flow.

The upper (grey (Spectra 12-strand)) rope shows the knot at an
intermediate stage, essentially a Water Bwl but w/Cow vice Clove
structure; in the lower knot, the continuation is shown with a
white (cotton) cord serving qua instructional-arrow where
the end is finally tucked -- a particular position here, for hoped-for
strength boost (nicer shape of S.Part curve), which is not important
in general use.  In short, this general knot can be formed with a
variety of particulars --just get in the two S.Part TurNips and the
three end-tucks.  I tie it by the rabbit-&-tree-&-hole method with
the base formed in the S.Part -- a timely method perhaps but not
overly complicated and too much to ask when you're about to go
spend a lot of time climbing & (re-)falling (or to put heavy load
on serious rope for which easy untying will be much valued!).


[Inkanyezi] gone

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #130 on: November 10, 2009, 10:28:26 PM »
End loop is the proposed usage, but I envisaged that it might sometimes be used for tying around a rather large object, where ring-loading would occur. For tying into the harness, I would prefer another knot. My own climbing has only been in masts, and I always used a bowline, which never has failed for me. On the other hand, I use an 11 mm hollow braided nylon cord that has a very good grip and I have so far never taken a fall with that kind of equipment. I have tried the fig8 rethreaded but think it's overly complicated without adding anytning for me. In situations with repeated dynamic load the bowline might behave differently, and kernmantle rope is a very different animal when it comes to knotting.

So I guess it must relate to the job at hand. I know that the single becket hitch does the same job as the double, but I usually make it double. The double can sometimes be easier to untie. The becket hitch is somewhat different from the sheet bend, but of course different cordage may fare differently. The rope I am used to is a lot softer than kernmantle, so it might behave differently.
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Dan_Lehman

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #131 on: November 11, 2009, 07:13:25 AM »
...it would help here if... one spoke/thought of How should this material be knotted?

kernmantle ropes range from highly elastic to highly inelastic; from slick & smooth-surfaced to less smooth (i.e., worn by use, sometimes to fuzziness) & less slick.  In most cases, they tend to be fairly firm, though here too have a range from those whose cross section flattens somewhat at bends to those so packed with core strength and snug mantle that they hold a round cross section and bend only grudgingly.
 
So, of WHAT rope material are we speaking of ?

Common nylon kernmantle climbing & SAR ropes, principally.
The main characteristic that they do NOT have is the supple flexibility
of even trawler hawsers (some), which can lazily be folded back upon
themselves.  For the most part, I guess that some of the notoriously
stiff ropes --either well-used old ones, or the PMI "pit"? ones-- should
be regarded as special cases, though we might adequately handle them.

Quote
 The more complex bowlines I proposed ... Been used by the professional fishermen from times immemorial,]

 ???  So far as I'm aware, they are "new" knots as of your
presentation here; I have never seen mention of such eye knots.
And the dropper knot that is formed in the bight doesn't
begin with a Slip knot, but with many wraps, the bight
tucked only later; this knot is to be set so that it resembles
the Blood knot properly set in monofilament fish line -- I must
add this last clause because the Net (and books) have shown
a misformed knot, S.Parts twisting from center outwards,
vs. going straight to opposite ends and coming back with
overwraps to be tucked through the center.

(Incidentally, I've never seen it pointed out that, as the dropper
formed in the bight (vs. making an Overhand), it is asymmetric,
and might be better oriented one way than the other (as it is
not such a strong knot -- some authors make it seem odd that
it isn't as strong as its lookalike Blood knot kin w/o noting the
obvious difference in loading from the eye).)

Quote
And I have to repeat, ... that one of those knots that can be tied with the same dropper loop "base" method
is the Janus bowline itself, in its mirrored form, a not-so-absurd knot that lies in between the "normal" and Eskimo
bowlines and the "dropper loop bowline" I proposed.

I've re-read your posts and don't see quite this particular assertion
realized -- you state it, but you show something different:  it has a
"Myrtle" bowline S.Part collar, not a (regular/Janus) collar formed of
a bight extending from the nipping loop.

And I have had quite some time trying to tie the knot in some softish
laid 3/8" nylon rope, which adds to the difficulty its grooves/ridges,
yes.  But I simply do not find the slip-knot tying method all so easy
or so reliable (esp. w/vagaries of the capsizing to the ultimate geometry).

I have played with a similar knot, formed by collaring Eskimo-wise first
and then collaring the S.Part -- and thinking that as long as one collars
both, the order isn't critical, and this might help those who sometimes
do the Eskimo by mistake.  But, then, it's a rabbit-around-tree tying method,
for the quick-tie by capsizing turNip into S.Part orients the end with wrong
entry (an anti-bowline entry is needed).


Quote
the EBSB and EBDB with a Yosemite finish ( fig. 24, 26 ), are also more complex and
less easy to be inspected forms of  bowlines , but supposedly more secure end-of-line knots, too.

I've tried desperately to kill Agent_Smith's infatuation with the @&*&@ "Yosemite finish"
-- but so far he carries on as if it were handed down from On High.  The EBDB devoid this
gratuitous finish is plenty inspectable/respectable, though it's yet to receive much of either.

--dl*
====

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #132 on: November 11, 2009, 09:01:57 AM »
I can see the virtue of the Janus Bowline in stiff round-profile rope, where the nip may be poor due to stiffness, so that the nipping loop tends to be kept open by the springiness of the rope itself. The Janus Bowline has better fill in the nipping turn, while at the same time providing more friction and securing the end. I cannot see how an eye tied into the harness would receive offset load, and when I have tried the Janus, it is not extremely good at handling ring loading. It can pull a considerable part of the end back when it's ring-loaded, so I'd go for a long end if ring loading is expected.

It resolves a puzzle for me, because it seems as the springiness and resistance to bending in addition to the round profile is what resists knotting that works well in other materials, and maybe that is the reason for preferring knots as the water knot and double fig8, as they have more fill and work with larger bight radius. The same properties help a lot in keeping a knot from jamming and to facilitate untying, by simply pressing the parts into the knot to open it.

I have played around a little with a stump of discarded kernmantle that I got, and one of my old lines displays some of those properties. That line is not safe for tying a bowline, because it will not nip unless deliberately dressed to nip and maintained so until load is applied to it. Water knot however works fine as well as the Janus Bowline.

I use the slipknot method extensively for tying the bowline, because for me, it is the fastest and simplest method of tying, and it is consistent and will form the knot dependably, provided the end is held away from the SP when the knot is drawn tight. This works in any material, but the doubts about kernmantle and how it would provide nip remain. It springs back and releases the nip as soon as it is left to itself, and then the end may work itself out of the knot, widening the collaring bight and ultimately maybe undoing the knot. So what works in a supple material is different from what would work in a springy and form-stable material. The slipknot method is not practical when the SP is away from you, as when tying into your harness. It is designed for hitching to a closed structure and working away from the SP, as when tying up a boat. It will of course work when you wish to attach a line to someone else, as in the firefighter case, but again, kernmantle rope raises serious doubt about the security of the bowline.

I have tried to combine the last tuck of the Janus Bowline with the slipknot method, but I don't find it very easy to accomplish. It is a bit easier just to make a round turn with the end around the nip of the bowline and up through its hitch to get more fill, but all those variants are difficult two-hand operations that might not be the easiest thing to do if you are in a situation where you also must think of your own balance and safety. If a carabiner might be considered, maybe it would be simpler to pre-tie a large loop with a knot that provides a smaller loop where you could connect the two with a carabiner, so that you would not need to rely on tying a knot. I have tried making the Butterfly with the doubled rope, and it works well, although it violates a few of the proposed requirements.
« Last Edit: December 19, 2010, 02:18:14 AM by Inkanyezi »
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Dan_Lehman

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #133 on: November 12, 2009, 06:40:52 AM »
Inkanyezi, I don't see the slip-knot method for tying a bowline all so
unusable in tying to one's harness; why do you?  As for some of the
hype re this method's quick efficacy, I've had partial capsizing when
doing that, to check it, where the result wasn't as intended.  And that
was with an incomplete transformation to setting the collar; it can go
the other way, too, I think -- collar too large.  So, there is likely some
need for further attention, to dress.  (I'm thinking of the Brion Toss
Rigger's Apprentice example where as a boat moves near
enough to a pile the rope's cast around, the Slip-knot bight gets the
end, and --whizz-bang-poof, voila-- continued boat movement capsizes
a beautiful bowline.  Except it might not.  I think in such a situation
I'd feel surer about putting in a HHitch and then a Rolling Hitch behind
this initial guard structure (which would buy me time to tie).

Ring-loading a tie-in eye, btw, seems to be a possibility for some who
choose to use this eye qua belay loop, clipping their belay device to
it (as opposed to a belay loop usually in a harness).

You mentioned the Overhand (& Fig.8) eye knots as being compactly secure.
There is some favor of the variation that brings the end into tracing the
base Overhand from the opposite side (i.e., same side as S.Part)
which I guess one could think of as a corresponding eye knot to the
Offset Ring Bend ("EDK").  It tends to be more easily untied; ring-loaded,
it is a Ring bend (stronger orientation).  But it's not Post-Eye Tiable.

I found a way to simulate this eye knot in a PET form, and it
looks, hmmm, maybe okay (maybe it's the ring-loading aspect that
was less impressive).

Quote from: xarax
The more complex bowlines I proposed ... Been used by the professional fishermen from times immemorial,]

 ???  So far as I'm aware, they are "new" knots as of your presentation here; I have never seen mention of such eye knots.


 ??? As I have said, ...

I quoted what you said, which needn't be repeated:  that the oddball "bowline" was
used by fisherman.  And I said that that was news to me.  If you have any documentation
of it, we'd like to learn of that.  --not the method of tucking a bight to make a
dropper loop, but the actual resultant eye knot suggested by you here.  I am unaware
of any hint of such a knot, from any literature I've seen.  And, frankly, the results are
such that I don't expect to see them.  The SINGLE bight tuck, and the capsizing of
that Slip knot to suck in a snood into a Sheet-bend-like (or reverse) form, yes, that
I've seen; but nothing beyond that.  Nor have the mid-line dropper eyes been formed
as you show, but rather with a bight wrapping several times and being tucked once,
resembling a ends-on-same-side Blood knot w/ends fused.

Quote
I attach the relevant picture again, with the name "Eskimo / Myrtle "bowline that I now prefer, after your remark.
Please take another look at it, and tell me if it is promising as a more secure form of bowline for climbing/rescue purposes, as the Janus bowline itself is.

A rose by any other name ... :  renaming (and re-posting the photo) isn't
going to help the knot.  This is a lousy knot for the target material.
It takes a bit of working to get into final form, too, btw.

(Where's Alpineer in all this, btw?  His climbing ropes should have many fewer
"new" knots recorded in them and thus be freer for this try-&-see play than
mine.  (But I did just give it a go in old smooth firm 11mm dynamic rope.))

--dl*
====

[Inkanyezi] gone

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Re: Janus Bowline or an equivalent secure bowline for climbing/rescue purposes
« Reply #134 on: November 12, 2009, 11:04:28 AM »
Inkanyezi, I don't see the slip-knot method for tying a bowline all so
unusable in tying to one's harness; why do you?  As for some of the
hype re this method's quick efficacy, I've had partial capsizing when
doing that, to check it, where the result wasn't as intended.  And that
was with an incomplete transformation to setting the collar; it can go
the other way, too, I think -- collar too large.  So, there is likely some
need for further attention, to dress.  (I'm thinking of the Brion Toss
Rigger's Apprentice example where as a boat moves near
enough to a pile the rope's cast around, the Slip-knot bight gets the
end, and --whizz-bang-poof, voila-- continued boat movement capsizes
a beautiful bowline.  Except it might not. /.../

Of course it may be usable, but then it would force the learning of a different method to form the slipknot, which of course is feasible. However, I don't see the virtue of it, as it would not in my eyes be superior to the twist-of-hand method mostly used. Thing is, that the method I use for forming the slip-knot bowline consistently forms a perfect knot and never misses. I got the idea from Brion Toss, I shall not deny that, more than twenty years ago, and trying his suggested slipknot, I failed to collapse it into a bowline about four times out of five.

Thinking that there must be something I do wrong, believing that Brion would not be totally off, I tried to figure out exactly what went wrong. The things that were missing was the position of the end and a firm grip on it while drawing up the knot, and a sufficiently open "slip-knot", which should in fact be more like a marlingspike hitch than a slipknot. So those are the two essentials for reliably using the method. The "slipknot" is not a slipknot but a marlingspike hitch, and the end can not be left to its own devices, but must be firmly held away from the standing part, thereby forming the collaring bight, around which the TurNip/HH will be formed upon pulling the SP. It can all be seen at the video clip I made. The video clip (in Swedish) is at:
http://www.youtube.com/watch?v=WTApTsLIe1g

About one minute into the clip, those two essentials may be clearly observed. The open slipknot/marlingspike hitch, and the end that is held away from the standing part. At about 1"45' into the video, I form the marlingspike hitch by the "soft method", which does not require any twist of the hand. This is important ergonomically, and in this way I can form the knot in a hawser. I do it in a fluent movement, only lifting the end, hanging a bight over my left hand, then lowering the right hand to grip the bight of the line with my right hand. Then I lift this bight, which forms a round turn at the level of my left hand, where I push my fingers past the lifted part and back through the round turn. This effectively forms the "slipknot", or rather a marlingspike hitch, around my left hand. All seems a rather loose tangle, but it is very organised. The next movement is to put the end through the structure where the line is to be attached, it may at this point be passed twice for an extra round turn, and this is done without losing grip of any of the parts. Then, when the end is hugging the belaying point, it is gripped with the left hand, pulled through the marlingspike hitch and held away from the standing part which is pulled. The marlingspike hitch then conveniently rolls over into a half hitch, which elegantly rolls over the bight formed by the end.

I have done it so many hundred times without missing once, that I regard it as quite reliable. Like any choreography, you have to learn the steps and turns, but the end result is consistent. Generally, the knot is completed between three and five seconds after gripping the end of the line. I trust the method so much, that it has become my standard way of forming the bowline wherever it is to be attached to an object that I am facing. It is a fluent movement, choreography is not a misplaced term, and I have done it in situations akin to the one Brion Toss describes. The difference: It is reliable, the knot will positively take its final form each time. There's no snag, like when the slipknot is drawn up as in Brion's picture, and the marlingspike hitch rolls seemingly without resistance into the nipping hitch of the bowline. Brion's sketch and story was my inspiration to invent a reliable way of tying it, as I found it unreliable and dangerous as described, although it seemed to have potential. It has!

So I never do it in the way described in The Rigger's Apprentice, I always make sure that:
  • the marlingspike hitch is open
  • the end is held away from the standing part when drawing up
So much for the whizz-bang-poof. It needs the help of a keen hand.
« Last Edit: November 12, 2009, 07:51:06 PM by Inkanyezi »
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