|By Chris D. |
May 3, 2012
Hey everyone, I should preface this with I searched for this subject but didn't find a whole lot.
My question is when building a top rope setup which knots are solely for webbing and which are solely for static line.
I was recently taught anchor building and can set up all kinds of anchors, what I didn't learn was is it possible to set up a clove hitch on webbing? Often they would use the clove to equalize the anchor on one end (if using one piece of static) and it was a breeze. I trusted them and the 3 other anchor points we made and found it was taught and never slipped. Yet I was also informed that the clove can really only handle 800lbs of load before slipping.
So my question has a few parts, can you actually use a clove on your anchor?
-Can you use the clove with webbing, thus using the clove for making an anchor with webbing?
Is there a list of knots you can use with webbing as opposed to static line? I assumed most of the friction knots were a no go with webbing. But I thought I'd ask here since I'm not terrible keen on buying or carrying around a static line unless I have to.
|By Auto-X Fil |
From NEPA and Upper Jay, NY
May 3, 2012
I used to use webbing a lot, but I've switched to static line. If you're setting TR anchors, weight is probably not a huge deal.
Rope has all the loadbearing strands protected by a sheath. Webbing has them exposed. The resulting difference in resistance to cutting and wear over edges is enormous. If you ever have your TR setups drape over an edge - which mine almost always do - use static line.
That said, I never use clove hitches in webbing.
Cloves are reported to slip under load, but I don't think this happens with cordage on carabiners. Check this out:
|By randy88fj62 |
May 3, 2012
You should take a class from a trained professional. Supplement that with experience from people you trust. Spend $30 and buy an anchors book. The book answers your questions and more.
Directly answering your question:
Use triple fiahermans to join two ends of rope. Use a water knot (aka ring bend) to join two ends of webbing. I have never used a clove hitch on webbing, never seen anyone do it, nor have I ever read anything about that in writing.
I use 11mm static cord to set up my top rope anchors. Rope has a sheath protecting it's core. Webbing does not have any protection. If you are using webbing as your anchor material; look for sharp edges and other potential damaging features (I.e. Pinches.) Always build a redundant top rope anchor, never rely on one object (i.e. A single tree.)
|By steitz |
From midcoast, maine
May 3, 2012
Most knots should not be tied in webbing because they won't hold due to lack of circular geometry in webbing, (think of a transverse slice).
The only knots that I have heard of being reliable in webbing are
1) the water knot
2) the beer knot
3) overhand knots (as either slip loops or for creating nights, etc...)
4) clove hitches, though not in the application you've described - rather on slings for tricky nut placements.
As far as clove's slipping under load, a properly made anchor will evenly distribution the force on it enough that the amount of force on the clove ought to be well below it's threshold for slipping.
Lastly, as a just so you know tidbit, all knots reduce the strength of the material they are tied in significantly. Climbing cordage is engineered with these reductions in kind, but it's useful to know which knots reduce the strength of materials more or less.
The physics of it all is fascinating, and definitely worth your while to get into.