Low Friction Ring strop methods survey

[Seaworthy Lass]

Originally Posted by Breaking Waves

^^ the Hampidjan is specifically for dux, a heat set product. The specific curve/numbers change a little but the general characteristic of the curve are common across high modulus fibers (and wire).

I can’t comment on the soft shackle vs cow hitched strength argument. Would need to see test data. As we have seen here, actual testing can reveal things, different that we (or at least I) expected.

I do agree the soft shackle is a more versatile attachment than the fixed loop. On the flip side I worry that it adds a level of complexity, on top of the ring connection construction, which is daunting for DIYers and could introduce construction defects which weaken the end solution.

The lab did offer to do another round of testing if we had “ improved solutions”.

Given nothing failed at the LF ring end for all five samples you constructed, I can’t imagine loops could be improved over and above this, as the weak point is at the attachment end.

In practice, loop strops will be far less strong than tested (possibly less than half the strength tested) if cow hitched onto attachment points around the same diameter or even slightly higher. Load testing results on cow hitched loops have already shown this.

If we are trying to maximise the strength of strops used for LF rings, I do think soft shackle versions are the way to go. I agree though that they are harder to make if someone is not experienced with soft shackle construction, and also there is room for more error if some basic care is not taken. Even manufacturers get this wrong - eg I have seen Kohlhoff style soft shackles with diamond stoppers for sale with eyes that are barely one rope diameter in size .

SWL