naturally straight angle of the standing ends is a testament to its performance.
Rather, the cited "straight"ness is evidence of viewer perspective.
Consider that these SParts reach in to opposite sides of what
Xarax referred to as a "hinge", "pivot" line (IIRC) --so they must
deviate from the to-be-tension-aligned straightness in order to do
that, being curved at the collars. Is this any better than curvature
in the
water knot (which seems minor, in rope)?
I have discovered some ways to get a real straightness --absolutely
NO curvature until turning around material (and there curvature
is uniformly across the width of the tape --ideal!)--; but I suspect
that when push comes to shove (i.e., the severe forces toward
rupture point), the fact of non-rigid material being wrapped will
become clear, and a curvature across the tape width will obtain,
and "ideal" results won't, alas. --nice to look at, though. (And,
at least, there is not the *active* constriction of the SParts as
in the
tape/water knot but something more *passive* --i.e., the
tape pressing into this deformable (but not constricting) collar.
Attached here is a photo of some end-2-end knots in both common
1" tubular nylon tape (the colored, larger stuff), and in 5/8" and 3/8"
(just one in latter) lubricasted-polyester cable-hauling tape. The
familiar knot is shown for comparison purposes; note that this
knot is
asymmetric --hence, the blue end lies "exterior"
(my term) and the yellow is mostly hidden by it. In some
tapes --those that are stiff (possibly aged 1" tubular vs. new),
is one conjecture--, it would be the exterior end (blue, here)
that can be worked out of the knot in cyclical loading.
To redress this occasionally witnessed slippage, I discovered
a way to bring both tails out on the "interior" side, and the
knot is rendered
symmetric by this revision. (It is
easily tied by first making a loose
fisherman's knot and
tying one
overhand component so that its tail interlocks
with the first-tied component, and then dressing.) Recently,
in looking at this revised,
symmetric water knot, I wanted
to put the SPart's initial turn where the tail had been, but still
lying *exterior*. This is seen in the 3/8" tape's knot, which
lies atop a yellow tape, upper-left, and above the original
symmetric revision in blue & yellow 2 knots down. My
thought is that the turn of the SPart is more towards being
perpendicular to the axis of tension, and this might help
keep the force evenly distributed?
(A fellow once on RC.com tested the initial knot along with
the common one and IIRC there was slight plus to the former
--enough of a result to give some comfort that it wasn't a
weak alternative, at least. Rupture seemed to come near
the point of entry, though one specimen showed the start
of tearing at the *peak* where SParts bend against each other.)
--dl*
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