The end-2-end knot I recommended above (post #47),
Ashley's #1408 (and simiarly his #1452, which is
more commonly presented) with the extended tucking
I describe should hold. Or else it will exhibit a new level
of rope fluidity, I think!
Well, then you will be able to learn something today . . . it slipped at 630lbs,
about the same as the double fisherman I just tested (post above).
630lbs (27% of rated line tensile) was the 'loop load',
so the knot load would be (very roughly) half of that.
I have pictures . . . but they just show the tails sucking into the knot.
Actually, they show more : they show that the
knot wasn't correctly tied --there should be equally
two turns of end tucks showing on either side
of the line, but there are three on our/viewer's side
(only the leftmost turn runs behind the line, the
others are over). Still, you have extra tucks
one way or another, and that they can all slip
--and so evenly, as seen in both tails--
is indeed a(nother) eye-opener! Egadz!!

One throws away the old playbook!
> Just FYI . . . The knot as shown in your picture,
> without the extra tucks, slipped at 295lbs.
I thank you very much for this extra information.
One could endeavor to engineer the knot so
that tail-tucks went in opposite directions,
in hopes that maybe removing *sympathetic*
movement might help, but I want something
simpler and more sure.
I can think of one simple adjustment to the
interlocking of
overhand knots such we have
in #1408, Shakehands, #1452, zeppelin :
at the point of the "U-turn" of the
overhands,continue turning and make a full loop (as with
a
bowline) and
then to the collaring, now
thus around the opposing S.Part. Might this added
surrounding of constricting parts succeed?
(Although in the above cases even though neither
individual S.Part surrounds --they make 180deg turns--,
they
jointly surround. Still, the full turn seems
a significant adjustment.
(And the
mirrored bowline held, yes?)
--dl*
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