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Here is how I do it, and I was wondering if it's correct, because it differs slightly from what Jepson has in the Climber's Companion. But I think this looks neater! mateo
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Boy, this thread is generating a slew of confusions to chase, and I'll do my best ... !
Firstly, to the OP, you are correct in noting that
<u>On Rope II</u> (& 1st ed.) illustrate
a DIFFERENT dressing. (TreeCo, look closely.) Your dressing has the end making a 1-dia
bend around one leg of the eye, whereas another dressing has the end bending more
nearly 2dia, around both one eye leg and the SPart (in a non-perpendicular way).
I've always regarded the YoBowl as a lame way to secure the Bowline. The need for
security in climbing/caving kernmantle ropes arises because they are rather stiff & slick,
and the unadorned Bwl loosens (which can lead to coming untied or to capsizing upon
loading--neither being desired!).
But precisely this need to accommodate stiffness begs the question of using a tie-off
that somewhat requires the end to make a 1-dia bend! Moreover, the binding of
the end by the knot's
collar bight is a bit dubious--the collar is also of this
stiff material and so won't readily wrap around 2 circles but form more of a 'U' shape
within which the end & SPart can shift and lose binding. (3 round cross sections
better approximates a circle to wrap around, not just the two.)
Arborists use some ropes that are more flexible, and one can see the knots being
more easily drawn up (an antagonist to this is the notoriously stiff PMI MaxWear!).
There is some risk that the YoBwl will be disoriented upon setting if one is careless;
in the 1st ed. of
<u>On Rope</u>, the chapter cover page photo of two loops
shows a poorly dressed Fig.8 and a grossly misformed YoBwl, where the SPart now
bends around but ONE dia.--the turn of the end having been pulled free of the
SPart's loop/roundturn.
And there's a simple alternative with similar tuck, as shown being tied in the bight,
at
www.iland.net/~jbritton/KnotPhotoContributions.html
in which the end's tuck makes an Overhand (and which end could serve qua SPart).
The End-Bound Dbl.Bwl is made by following that
<u>On Rope</u> illustration 3-9a
and then continuing to around behind the knot and right back through the hole
adjacent to the first end-tuck--a loop-de-loop finish, if you will. This loop thus
binds the turns of the Bwl and keeps them from loosening, when set; the binding
turn however is not loaded by knot use, so doesn't jam (indeed, if not set pretty
tight, when the knot's loaded the reduction in rope dia. from elongation will actually
create a small gap between binding loop material and what's bound). Whether
one needs such security is a separate question; the EBDB takes a bit more fiddling
to untie.
Another simple securing of the Bwl can be had by taking the end around the legs
of the eye almost as shown in
<u>On Rope</u> 3-8a--BUT BLACK ARROW SHOULD
come around OVER BOTH legs--and then tuck the end out as a half-hitch,
going under itself AND through the "hole" (this is more easily seen looking at
the knot from the other side. "doubly tucked half-hitch" I'd call it. What it does
in enable the Bwl's "hole" (loop) to be held pretty secure, enough to prevent the
SPart from feeding into it & loosening. (Set w/iterative pressing HH up against
knot, pulling eye leg, pulling end.)
> Because it has a bigger radius bend (2 parts of rope) at the "horseshoe",
> it adds about 5% strength to the knot.
Remarks about which form is stronger should be dismissed as irrelevant, for strength
shouldn't be much concern if working within work-load limits (safety factor);
where some misjudgement of rope strength vs. load occurs, it probably will not
fall within the relatively small difference between knots--YMMV. In any case, for
these two versions/dressings of the YoBwl, the SPart's bend is really the same (around
2 dia), and its critical geometry at crunch time could depend as much on setting and
rope type as the dressing. The "horseshoe", which I take to be the "collar", isn't where
the knot breaks, surely--rather, somewhere in the "hole"/loop turn, unless one has
dressed & set the knot with the collar drawn extremely snug! (In many yachting
photos of Bwl.s, one can see a quite loose/large collar such that the crossing of
the SPart's loop barely touches (en route to opening further, into a sort of coil,
en route to capsizing if ... ). It's a different story re the Sheet Bend.
-------
A word re TreeSpyder's remarks about ropes of polycombo (PS+PP) vs. pure PS:
it should be the case that one will begin to see "copolymer" oelfin fibres used vice
PP, and these fibres have much greater strength than PP--nearly as much as PS,
yet still with PP's lightness of being. I should think that the "filler" PP fibers not only
lighten the rope but also give a different and perhaps preferred handling characteristics
--the PP being flexible yet a bit springy!?
-------
A word re words: "bight" is the shape, not "bite" (as in "Bowline with a bight").
"ring-loading" is a good term for the isolated loading of a loopknot's eye, as
e.g. TreeSpyder shows in one image. This loading can spill a ("right-handed")
Bowline; a (so-called) "left-handed" one will tend to lock in a form known as the
Lapp Bend. (Anecdote of SAR trying to hoist injured climber by clipping into Bwl eye
and having it spill and kill him. A similar loading could result from something being
caught in the eye as a load is lowered. So, a reason to chose the "wrong" Bwl!)
"slip-knot": this is solidly confused. Ashley defines it as the Overhand knot with
the end finished with a bight, for easy untying, in contrast to the simple noose where
the SPart forms the bight. The latter is what one wants for that whizz-bang tying
of a Bwl--essentially forming a Marlinespike Hitch and then putting the end into it
as its object. I would NOT want to depend on that tying method working automatically
--it's too easy to see the end being pulled free before that noose in the SPart grabs
it and capsizes into the Bwl!
As for "Jacked", what TreeSpyder shows is quite diffferent from what Tom points to:
the former is known as the Eskimo Bwl, related to that Lapp bend; the latter the
"Dbl.Bwl", as someone notes, and also "Round-turn Bwl".
Which leads to the problematic "round turn": facing a tree, if the rope runs around
and back to ya, it's a "turn"; one more wrap makes a "round turn", by common
parlance. But what if the rope goes around the tree and AWAY from ya?
In degrees, 180 & 540 are the agreed cases (as in "Round Turn & Two Half-Hitches");
but what of 360, 720deg. ? --a muddle! But the "round-turn Bwl" took the 720deg
dble.turn as one not two RTs.
.:. You'll encounter differences on this (but "RT&2HH" is quite common & old).
*knudeNoggin*
