It would appear the sheepshank has fallen into ignominy.
Scoutmasters and firefighters now recommend against
its use.
http://www.animatedknots.com/sheepshank/index.php
Funny thing, though. I use it quite often in an application
for which it was certainly never intended: as the pulley
loop in tackle arrangements such as versatackles or
trucker's hitches. This may be folly, but as a knot user
rather than a knot theorist, I've had no incidence of failure.
The knot seems to collapse only under extremely heavy
loading in slippery rope. Repeated, violent shocks
also seem to do it in . However, if the pull is
strong and steady, all's well.
The idea came to me when I was looking for a non-
jamming alternative to a loop that gets heavily loaded.
I'm well aware that knot tyers have their favorites (the
butterfly comes to mind.) The "public" uses a slipped
overhand for the loop, possibly the worst choice from
the jamming perspective.
I happened to see the tem****ary loop suggested in
knot books for use with a "Waggoner's Hitch." (See
Des Pawson's "Handbook of Knots, Expanded Edition,"
1998, for example.) This appears to be but half a
sheepshank, with a twisted lower bight used as the pulley
loop. I guess the idea is to have a loop that cannot
possibly jam up after use and will simply disappear
once the load is released.
Now, this is one VERY unstable knot, one that has to be
perfectly constructed to have any hope of fulfilling its pur-
pose. So, why not complete the sheepshank and use the lower
bight for the pulley loop? Using the old "three crossing turns"
shortcut
http://korpegard.se/knot/?knot=18&hideComments=&showInt=
makes it as quick to tie as any slip loop. The (mis)use of the lower
loop of a sheepshank does not appear to upset its gripping
turns whatsoever. As long as the pull is strong and steady the
loop will hold just fine, which is the condition one has with a
versatackle or trucker's hitch. When the task is done, the knot
practically unties itself.
Naturally, if my load is ****fting or I'm trying to hoist my 350 lb
buddy with a slick string, all bets are off.
Luke in Ca
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