I tried with two turns, but then the double turn is like drawing the ends through a pipe,
it won't twist back under tension, as the double turns provide leverage,
and friction in the remaining elbow will decrease the nip of the turns.
It becomes more difficult to set, and the nip seems poorer.
Interesting. I'd post a photo, but am not eager to click-&-download for
just that.
As what I just did, upon reading this report, it to run some 5/16" (hard
to figure hollow-braid size) fairly slick (but collected
from the Wild)
PP hollow-braid (quite compressible cross section) through an oval
'biner (very smooth, round, 1cm dia) and a slightly fatter hook of
a 5:1 pulley, running the ends through a double turn of the continuous
side of the simple loop (two strands bearing load). I tightened it pretty
easily, and then stood on the pulley.
NOW, "5:1" is TMA, but as it's a quite lousy (one bad sheave) pulley,
let's chop actual MA by half: 5x180=900#/2 ~=> 400# say.
AND, after initial loading, I tightened the loop further (just hands),
and stood upon it again. There was little slippage (the sort of yield
that might better be seen as a setting-settling of material.
This hollowbraid flattens in the double loop, to a nipping width
of about 3/4"-2cm. Your 3-strand rope looks to be rather firm
and round (and *grooved*). => YMMV
!?
--dl*
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