termination knots

[DrewB]

What knot are people using to tie in with? im sure the most popular would be the fishermans. having been told to rethink how much tail to leave when dressing the knot-at least twice the diameter with anything up to 10x diameter- i have now seen destruction testingwith a 80kg weight dropped 60cm and the fishermans slipping straight undone! and only 60cms!!! the loadon the dynanometer reached up to 220kgs. it really reminds you not too climb far past your anchor point. and after about 6 drops the carabiner snapped in half..

[TreeSpyder]

Wow, those are some scary numbers!

 

i like Fisherman's/Noose/Scaffold/Overhand/Anchor to self to form Eye whatever ya call it with 3 turns. i think the more turns the more security; and perhaps the better dynamic absorption. i've never had one come undone; but that probably partially depends on setting and rope choice.

 

Those worried, might make a halyard; whereby you make a Fisherman's and fold the bitters back over the last Turn and under at least 1 of the previous Turns.

 

i'd think more line in the system would give less drama on dyno; but then doubling it over like we do in DdRt would give more by virtue of more tensile strength to the same load/ giving less elasticity. So there is more shock close to your TIP; especially in DdRT. i'm also thinking/hoping the human body; being not totally solid as a lead weight would not give as high numbers(?).

[Steve Bullman]

drew, i always use double fishermans. tests like these always make u question anything you're using though.

[Jamie]

splices

 

jamie

[Amelanchier]

splicetastic mate.

[bill]

splices are great but expensive if you cant do it yourself. im a bit suprised by these tests. i bet the test was done on a fresh knot. i only use fishermens for my lanyard but after a while when its bedded in and the loose end has shrunk i recon that it would work better then a new knot.

[DrewB]

yeah the knots were fresh but had been tightened by hand pretty tight. knot was a klemheist(it showed what could happen when transfering from footlock style into standard climbing tech) and it was an 80kg block of wood straight dropped from between 30cm and 100cm.it was just a reminder of worst case scenario really. also same weight was dropped 30 cm onto an ascender on spectra rope and it stripped the outer core of the rope off.its good fun seeing gear getting destroyed!!

[TreeSpyder]

What length of line elasticity was absorbing the hit?

[DrewB]

What length of line elasticity was absorbing the hit?

 

dyno was set at around 14m from ground and hitch was tied in at around 8m (i think). different ropes were tried, dyneema/spectra(the worst on ascender) arbormaster and some cheap samson stuff-arborplus?. the main lesson was (for me) was that if someone is learning to climb and therefore more likely to have a minor slip/fall then get them climbing on the old stretchy climbing line, itll be harder work for them but better to fall on.

We done some tests on footlocking and how much force was created by that on the tip but ill have to hunt the figures out.

[DrewB]

drew, i always use double fishermans. tests like these always make u question anything you're using though.

 

i would like splices or stitched eyes on everything but til i win the lotto the fishermans will do. use them everyday and never had a problem but after seeing them pull through i checked the ones on the people i work with, a lot of guys had only a couple of mm as a tail and its for this reason that these tests were done. interestingly the stitched eyes wer rated as better than splices as you can see whats going on better and ifs its been done correctly. all tests were done by Thilo Beeker of Nordic Tree care fame.