I have just spent some time verifying that the two tying instructions I gave for 1452 produce a knot topologically identical, and I believe identical in all respects, to the method indicated in Ashley's drawing.
I'm not sure you're saying what you intend:
topological equality
is irrelevant to
practical effects -- the
Anchor Bend has that equality
to the
Strangle hitch, but those are markedly different geometries
(it is a question lingering about what a
Uni-knot is supposed to be
-- transformed into
strangleness or left in a sort of reverse
anchorB'dness?!).
I found that for all three methods the bend winds up with each working end pointing toward its own standing part most of the time ... . They can always be adjusted to point either way by adjusting the way they nestle in the pocket in which they are nipped.
That points to unwanted ambiguity in the tying method, to leave
this important, behavior-(e/a)ffecting geometry unspecified.
(all of the tying methods under discussion, including Ashley's) produce jamming configurations. Besides, I just ran two tests, each with a different orientation of the working ends: they jammed equally.
Ashley's image etc. are ambiguous.
See here for a definite image of the knot:
http://igkt.net/sm/index.php?topic=1446.0Now, in this case, I left the
collars rather large, expressly so that
they would come up around the knot body; the ends could've pulled
them shorter and then they'd effect more of a choker-hitch geometry
at knot entry, and should
not jam. So, it is not only the orientation
but the amount of material in the
collar (and perhaps to that point
the elasticity of the material).
I also show a version of
SmitHunter's Bend that resists jamming pretty well.
One can achieve this version directly from the original, by just
loosening one
collar and then tucking the opposite (adjacent) end
out through it, making a sort of twist of the ends' passage through
the knot's nip -- dress to even this twist and have some bit of each
end within each
collar circle.
Surely there is some value to a tying method that eliminates
the flexibility of outcome you admire!
Rather, that "flexibility" is something to be specified per need
--I enumerated several of the interlocked-Overhands bends
that can result-- ; it's not something left to chance. (E.g., were
one tying together some of the common slippery-springy PP rope
for some makeshift dog leash or whatever, one might wish to use
a secure-when-slack knot such as the Jammed#1452, well aware
that untying would be easy in said material & loading; so, then
the ends would be positioned ... and the not set accordingly.
But for closing a rope sling used in impromptu towing of some
vehicle out of being stuck, another version would be deliberately
employed. The tying guidance needs to note the differences;
the image(s) should show the results clearly (unlike nearly ALL
anglers' knots images!).)
I now think that sailors of the old days of sail wouldn't
have had much use for Ashley's bend, because it jams so easily
Given some of the egregious misrepresentations of knotting history,
one can wonder at the goings-on in general. As Inkanyezi once said
here, in choosing a basic set of knots, bending ropes together isn't
such a regular need. In modern day, the popular Discovery Channel
t.v. series
The Deadliest Catch (about Alaskan crab fishermen) showed
the use of the Carrick bend to bend on a pot-line extension when
needed for deeper water; in some cases, I think that they might put
on a seizing of electrical tape, but not always. (I've been unable to
connect so far w/some fishers up there, but did e-chat w/one fellow
who'd gotten wet in that capacity (or had been in that neck o' woods).)
I just tried #1452 in 3/8" laid (medium) nylon, loading it with'perhaps 400#; it didn't jam.
Proportionate loading to your test, however, would've taken maybe a half ton (I could try bouncing on the pulley ...).
[Roo] I'm unimpressed.
Roo doesn't impress easily.
I guess he likes exceeding
safe working loads?
In any case, I cannot say for sure what force I applied,
but when taking things even to 300# in material running
smack next to your vitals it is impressive enough for me.
That said, to satisfy the skeptics, I did much the same (but
with greater caution, LESS bouncing!) with the small size
of hollow-braid (16strand) nylon binding cord which is in
common use by commercial fishers; it probably has around
an 800# tensile strength? This material takes on a
flatprofile (like thick tape). #1452 in one version was able
to be pried open easily enough.
And I just tried lifting 62.5# (barbell weights) with thin,
nylon (polyester?) venetian-blind cord; lift-off was prevented
by a SNAP!!!
Maybe it got to 50# force, but ... --100% plus.
The break was at #1452, not the
Dragon eyeknot or the double
Pile Hitch around a pen; the knot remained intact, with the
break point right at the entry/
collar area yet holding well
enough for me to see that the opposite collar could be easily
enough pried back. (Maybe the real problem is that you're
inept at untying?
)
Round#3: Just tried this with a jamming version and used
just 50#, but had the same result (and it both cases the
break was on the lower SPart) (!); the opposite
collarhowever was still able to be pried off, pretty easily (I don't
think this would be the case for serious material --rope!).
As for more exact size/info re this fine cord, hmmm: it is
just less than 1/16th, >1/32, and a guesstimate of 1.8mm
is, well, in the ballpark such as one can be sizing tiny cord
with a (crudely?) marked rule. It has a single core strand,
and (I think --but it's hard to see) over-2/under-2 braid.
But you might want to try using some barbell weights
to get a better feel for force: if this stuff breaks at >50#,
you might be also down in this force region, though I'm
not going to equate strengths as clearly this stuff needn't
be all so strong for its task.
(I like to *harvest* such cords from discarded items.)
((Btw, seems to me that MY cord didn't have all so much
stretch, and I'll guess is weaker than yours, too (but one
can be surprised by what barbell weights show!).))
There's another version of #1452 which you should be able
to see from a critique of the Carrick, where you think "What
if the ends were run out up through the central nipping circle
of the SParts?" -- likely what led Ashley (and me) to it. Here,
jamming doesn't have a chance (but I'll guess that strength
suffers a little, and it's a bit bulkier). But THIS version really
does involve some subtleties of construction/dressing!
But surely the fact has some significance that Carrick, Alpine, and Zeppelin
are extremely easy to untie with bare fingers under these loading
conditions while Ashley's is impossible.... I may have made too much
of the significance of the difference for ropes that are not as stretchy, and I'll fix that,
but some attribution of jamminess should stick to Ashley's because of that difference.
The "
Alpine": somewhere along the line "alpine" got worked into
someone's notion of name for this. There is some thread on origins
on this site (Search; and include "Thrun" in keywords). In short,
C.L.Day pointed to "linesmen's loop" having publication antecedent
to Wright & Magowan's
Alpine Journal presentation of the
eyeknot
in 1928. A caver-auther, I think, might've decided to qualify W&M's
"Butterfly" with "Alpine" in contradistinction to some other such knot
that can be tied similarly (Slip-Knot & Half-hitch'd end). And it does
nicely fit the medium for W&M, but ... ; I prefer to leave it off, and
not gift this other knot with wings. (I don't mind the other knot as
much as some.)
Rosendahl's bend is probably the least jammy; I think it would serve
those crabbers quite well in their stiff, hard-laid lines!
For
security testing, one could tie a series of ropes/cords to
some stick and thereby deliver like force/jitters to the set of knots.
Then one could try dragging relatively unweighted knotted material
across some kind of rough surface (carpet, lawn), leaving ends not
so long (to invite their being pushed into knot). I think that this
testing is really going to be largely pass/fail. (Another test would
be to see how the knots behaved in HMPE rope, but I suspect that
they'll hold (but recalling that a Dbl.Bowline did NOT!).)
--dl*
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