Whether you think I was thinking is beside the point,
it is a question yet begging an answer, lacking in your reply.
Ignoring the question of your "tamper test" in which you found
slippage doesn't shed any light on the issue, either. You claim
to have gotten a trucker's hitch to have loosen by some mythical
Poldo-Tackle mechanism --slipping around three hard turns and
at least one strong nip--, and that certainly bears questioning,
still in the absence of any explanation (as you eliminate a
practical impossibility).
--dl*
====
Not trying to be mean, I don't know what you're saying.
I am saying this: you have made a couple of assertions without
giving any detail, which are hard to understand. How did you
bring ropes to near breaking strength (and how did you know
what the force was, that it was in fact near ...)?
(That is something one usually tries hard to avoid, and with ropes
(not string/cords) it requires considerable force, posing some danger!)
And what is this "tamper test" of which you speak, and by which
you judge many common knots as being defective.
Further, I have tried to find ANY HINT of the mythical
Poldo-Tackleslippage & loosening you claim to have found; but you give no
details of your "tamper test" by which you ...
I verified this when I put various slip knots through a tamper test.
I tried it with three different materials, more recently with slick,
new, nylon hollow-braid commercial-fishing binding cord run through
a 'biner anchor (a relatively broad, smooth, round metal), which I
could *strum* for vibrations.
Now, Roo suggests trying the
Poldo Tackle and seeing the behavior.
Yes, it can happen --just tried it with that hard, firm-slick-3-stranded
soft-laid PP 4?mm cord run through 'biner anchors holding 5# and
then 17.5#. Indeed, I had long ago built a low-friction Poldo Tackle
using another, maybe slicker PP cord (sent to me in frustration by the
sender and called "the Devil's cord!") and cut-out 2-litre bottle necks
for sheaves (broad, smoooooooth-slick); for I had come to conclude
that the
Poldo Tackle was theoretically (i.e., sans friction) unstable
--and, indeed, in this latest, low-friction construction, it quickly slipped
to full-extension lock (Roo's upper figure, eyes abutting) !!
But the
P.T. is a far cry from the
trucker's hitch workings, where in
place of simple eye one has a hitched eye (i.e., it's constricted)
--maybe two (i.e., the tied-off tail if hitched snug to the sheave-eye)--,
and possibly a constricted pair of haul lines (i.e., when one ties off
around the pair of down-to-&-back-up-from lines around the anchor.
AND one is unlikely to be using the slickest cordage available.
.:. I'm curious about what your "tamper test" was.
--dl*
====