Splicing Mercury Kernmantle climb line?

eyehearttrees · Apr 28, 2020

@Brocky do you happen to know of anybody doing dynamic break-testing on splices/sewings/slaices? Can't get it outta my head now Re spliced rigging cordage, the idea/fear that basically (or literally) all splice-testing is just static-testing, speed-of-force on the splice (on its "finger-trap resistance, specifically) has to factor-in to some degree I just haven't heard a word on it & google isn't being helpful :/

/have been exaggerating both crossover-throat length and tapers on my last few DB bull-rope splices...almost no 'proper' rope-research is done on shock-loading because arboriculture is the only niche that intentionally uses ropes in this manner, can't help but wonder if inclusion of dynamic-strength is what accounts for Teufelberger rating splices so much weaker than, say, Samson or Yale (who seem to say "expect 90%ABS, though ~100% is possible" - which is how I'd expect it, the eye's two legs each just needs to be 50%ABS and then it's the throat's ABS which I've gotta imagine goes up if exaggerating crossover length/gentler&longer tapering...would be longer splices of course but no harder to make, eager to hear someone's at least done crude basic testing to ensure dynamic-forces are still under splice-strengths!)

Brocky · Apr 28, 2020

No, but did look at drop testing of rope splices and came up with other interesting testing done on different double braid constructions and how they tested.
A full fid, 1/2 fid, 1/3 fid length buries were nearly identical for break strength. A 1/5 fid slipped out.
The same people were speculating that the amount of additional cover added to make up for the diameter increase might effect the results, too short of cover for the expansion not only makes it harder to do the splice, but might also be a larger stress riser making it weaker.
Different lengths of core in the eye were tested, their standard db splice only had minimal core past the throat. They tested different lengths in the eye, but when the first double braid came out, similar was done, but their testing showed the blunt end of the core led to abrasion, and the eye breaking most. I guess this is why the rope companies have the core going past the throat for various lengths. And a lot of rope company splicing instructions show the core only filling the eye and going no further. ?????