Hi Dan,
I am hoping that you can dredge up that previous report
of Mr. Chisnall's and whatever you can from Mr. Richards to share with me.
Chisnall's article should be findable via the IGKT
Knotting Matters Index, et cetera. Richards's
results were hosted by NSS, but then removed upon
someone's befuddlement with what should've been
recognized as a simple mis-labeling of table & data
--i.e., one rope's former matched to another's latter.
(I'd hoped to have helped Richards restore this long
ago, but things move (?) slowly.)
Dan, I tried the tails of the tape bight mutli-turn sheet bend oriented both ways and it appears to matter not one bit. The tape will bunch on the rope side at the tape bight tip and cinch down tightly.
Given the reaction of the tape to the constriction,
this isn't a surprising result. YMMV per tapes?!
But the advice came in regard to ropes.
As for the reverse of this where the rope is the bight with stopper (my add),
as I read your preference to be, the rope easily slid to the stopper
in the slick embrace of the crushed tape.
You mis-read my instruction : it is NOT the reverse,
except for the intial turn, minimal structure (i.e., the
Lapp bend is the reverse of the
sheet bend)
--which I do not recommend--; the subsequent wraps
of the
"multiple Lapp bend" go around only the hitching
line's (tape, by my reversal) & and bight's SParts, NOT also
the bight's tail (in the case of an eye, it can be of some
help to shorten the one side so to model an "open
bight" in tension, at least to give a little imbalance
in tension, as this seems to draw into a better form,
IMO). This shouldn't be so jammy --but I won't swear
that it's easily "forcibly loosen-able" everywhere,
just that it has some chance of this, especially where
forces aren't great--,
with ability to pull bight legs apart to pry out just
enough of the hitching SPart to enable the bight
tail to be worked free, and so on. --which is why
the hitching wraps must not include this tail
beyond the initial hitching turn!
Trying the tape wraps neatly laid atop each other yielded no better results in holding power,
Rather, that should do the opposite!
I've just re-tried what I recommended, using the only
readily grabbable volunteer material at hand --5/16" new
laid PP rope & some 3/4"ish solid lumber-binding nylon, PP?
tape. No hint of slippage.
(no mistying

)
It is recommended by other climbers, who appear to have considerable experience,
that if the original idea is to extend the rappel using tape,
[] it be kept as short as possible
What's "kept short"? --the length of tape? THAT
must be as long as needed to get down : there is
no choice that it be "kept as short ..." --you're down
or not! As for "considerable experience", I cannot
fathom anyone having much if any such experience,
unless by doing some experimental daydreaming
just in case ... ! As noted, experience has one prepared
with adequate rope.
I also am waiting for someone to explain how this whole
abseil structure is arranged, such that there is even some
theoretical possibility of extension :
what are the lines in play;
how are they configured (what is anchored to what);
what is the expected retrieval method?
We are thrust to the sharp end of some undescribed
rap line and asked to tie on tape; I don't understand
the context of this.
--dl*
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