What is the weight limit for safely descending on a friction hitch with a dynamic climbing system? I know there are variables such as type of hitch, type of rope, and friction from the tie in point, but I'm hoping to find some reasonably determined guideline.

Thank you,

Bradley Ford

Wow, good question!

First off, there are so many types of hitches a person could choose. And if you find one that slips at low loads, many of these you can just add a wrap or two to give a little more friction.

There are reports of prusiks and klemheists not slipping until the 1000lb range. This is not to say, "A prussik can hold a thousand pounds." Under the right (or should I say wrong) circumstances, they can slip at significantly lower loads.

Maybe we should set up a test.

love
nick

Nick,

Were the tests you reference done on a static or dynamic climbing system? And were they determing the weight limit for safely descending (controlled slipping with the option of stopping) or for causing the hitch to fail?

I have safely descended (knock on wood ) with a dynamic climbing system on 1/2'' XTC using a 5-3 Blake's; my climbing weight is ~175 lbs., so I can offer that the limit is at least 175 lbs.

Bradley Ford

My climbing weight is about 195, on the same system, and I've never worried. When I was taking my facilitator course, I also descended with Tim Kovar's, who's a lot bigger than I,weight on my rope, and was fine.

Joshua

Here is one test. Not super scientific, but it get's the point accross.

http://www.xmission.com/~tmoyer/testing/pull_tests_11_98.html

There is a lot of pulling going on there. The prussik info is down towards the bottom.

I've seen prussik hold many hundred pounds, and I've seen others slip at way less than a hundred. It's just a matter of trying it out low and slow. Get used to your materials. And take it easy when you try new things!

love
nick

Does anyone know if the ANSI Z133 safety standard covers safe descending weight limits for hitches with dynamic climbing systems?