This is a topic that has done the rounds all over the internet
and seems to fuel endless campfire debates at climbing areas...
Fulled by limited attention and wit. There have been some
inroads made, though, recently (hammering enough times
to make dents).
What is the best method of joining 2 climbing ropes together for a retrievable abseil ('Rap' for you Yanks)?
"ARJ" ("abseil-ropes joint/joiner/joining...") I call it.
Essential characteristics:
1. Ease of untying after loading;
2. Likelihood of translating around a 90 degree edge from low set anchor;
3. Relative chance of success in tying knot correctly (difficult to quantify);
4. Stability and security, including when joining ropes of different diameters
(Note; Strength is not an issue in my view).
Egregious omission :
capability of joining 6-7mm and 10-11mm lines!
And, for that matter, lines of differing natures other than diameter
(and possibly in addition to diameter).
Make it "offset water knot", perhaps : "ring bend" by some
conventional/historical senses ought to be a
hitch,
not an end-2-end knot; and "ring" has a good sense as
a type of object. (But this "ORB" should nevertheless
get the point across in the rockclimbing world, once
"offset" is understood.)
And that's clearly --by the same simple nomenclature--
"offset grapevine bend".
Nothing "stacked" really, just an
EDK (OWK (ORB)) with the
ends stoppered with an
overhand.Here is the simplest and likely best (partly for the
simplicity, using well-known knotting movements)
--the
offset water knot with the thin tail stoppered.
NB: it's not quite so simple as I make it, as the
particular orientation of the knot might help (but
all should work --TWO are shown here!), and the
particular orientation of the thinner (or more flexible)
line AND >>it<< being what is stoppered matter
(matter maybe not in ultimate success, but it should
be better).
--dl*
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