I occasionally place slings on rock spikes as trad climbing protection. If the spike is not very tall or thick the slings can become easily dislodged as the rope passes though the quickdraw/carabiner.

Is there a better technique to hold the sling in place? I have considered using a clove hitch but this isn't always possible.

I mainly use dyneema slings.

up vote 9 down vote accepted

Here are some ideas, with the usefulness depending on the terrain and rock quality and the terrain:

  • Hold it down with an upside-down nut: Place a nut below the spike and clip it to the sling. The nut needs to pull down on the sling so that the sling won't move. The nut will only need to resist being pulled upwards slightly since its only purpose is to prevent the sling from moving.
  • Tie it off: On some spikes, you might be able to tightly tie a knot in the sling, so that it is held firmly by some feature of the rock (e.g. a crack, or some kind of protrusion) which prevents it from slipping off. A simple overhand knot works well is many cases. Note: do not use a "self-tightening" knot such as a girth hitch to tie the sling around the spike. If there is no feature of the rock that prevents the sling from going up (such as protrusions or horizontal edges), these knots will tend to slide upwards and not down again and, thus, actually increase the chance of the sling sliding off!
  • Weigh it down: Clip some heavy-ish equipment (e.g. carabiners, hexes) to the sling, so that its weight counters the movement from rope drag.
  • Use fuzzier PA slings: Dyneema slings are often slippery. If all else fails, a slightly fuzzy (i.e. not brand-new) and wider PA sling will provide more friction with the rock and might better resist movement if the rock is somewhat rough.
  • 3
    Re the fuzzy slings: beware that if you have a sling with a cut of 25% of its width, the strength is reduced by 25% (as tested on a test rig). If you have a very fuzzy sling. many filaments have been cut and the total number could be a surprisingly large percentage overall which can reduce the strength by a similarly surprisingly large amount (again as per testing on a test rig). – Paul Lydon Aug 9 at 11:37
  • 2
    @PaulLydon is right. I was talking more about the "slightly fuzzy, more grippy" kind of sling, not about the "heavily damages, should be replaced" kind. – anderas Aug 9 at 12:07
  • I did wonder if a "larks foot" might be appropriate here? – Liam Aug 9 at 12:53
  • 1
    @Liam probably depends: If the spike has no constriction or narrow part, the larks foot will become tighter if the sling wanders upwards due to rope movement. The tightened knot will prevent it from falling down again, so it might actually increase the chance of the sling going over the spike. Same as with rock tunnels, really: There, a larks foot will make the sling wander to the thinnest (-> weakest) part of the rock. Here, it will make it go to the thinnest part, too: The top, where thickness == 0 ;-) – anderas Aug 9 at 14:04

Your Answer

 
discard

By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.

Not the answer you're looking for? Browse other questions tagged or ask your own question.