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Old 01-30-2007, 10:09 PM
Dan Lehman Dan Lehman is offline
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Join Date: Jun 2005
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Quote:
Originally Posted by Bob Pingel View Post
The figure 8 follow through was described as "ideal to attach two pieces of rope together" and was tested in that way.
Oh, thanks again, for that--in my hasty review of it ($5 is more than I want to toss
for it), I missed that point. From the knot pictured ruptured, they used what I call
the "perfect form" in "weak" loading--the inner twin taking the load instead of the
one reaching to the very end of the knot (along the axis of tension).

Results given for knots resp. in Dbl.braid Nylon, Sta-Set, Endura Braid

Cowboy Bowline: 55% 55% 38%

Clove & 2HH: 65% 63% 36% (looked to be maybe on 2" dia metal?)

RT & 2HH: {slipped @40%(5,148#)} {slipped @63%(6,492)} {slipped @29%(6,166#)}

Fig.8 BEND: 57% 52% 37%

Grapevine Bend: 54% 51% 30%

I'm REALLY surprised at the figures for the Grapevine bend!?
Too bad they didn't bother to stopper the RT&2HH (or make it 3HH) and check its
strength--or try the Anchor bend.
And with the hitches, there's a question about relative diameter of the hitched
object: some hitches will work well as ring hitches but not so well on spar-
or pile-sized objects. Note that the two polyester-sheathed ropes slipped nearly
at the same absolute load--which makes sense, if they're relatively similar in
flexibility/compressibility; the nylon, sooner.

rate of pull: 1 foot / minute

(They mention the hi-mod cordage being stronger than steel pound for pound:
heck, way stronger; sometimes as strong per diameter!)

--dl*
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Last edited by Dan Lehman : 01-30-2007 at 10:14 PM.
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