Talk:toe jam

toe jams in rock climbing

Info for the confused or skeptical: The easier-to-picture cases are where the parallel or intersecting surfaces are vertical, and the jammed toe is providing roughly upward force.

The parallel surfaces would almost always be a roughly vertical crack -- almost certainly a crack, not just geometrically, but because the rock had a hairline crack (usually from shrinkage as it cooled from magma) and the crack got opened up (usually from ice forcing it open as it froze). And the friction of the shoe against the walls of the crack (and/or maybe some pressure against teeny ledges on those walls) is what keeps the foot from sliding down the crack, and the climber from either having to depend on other holds, or falling. The crack probably won't hold against enough of the area of your horizontal foot, and maybe not even be wide enuf to let you put any significant length of your foot in horizontally, so you may put your foot in vertically, and bring your lower leg back toward vertical until enough of your foot is being crushed into less than its normal width that you get really great friction; really serious climbers think that's great fun.

The intersecting surfaces would probably be nearly vertical, facing each other like the walls of a room (rather than a corner of the outside of the house) but of course probably not at 90 degrees, and not necessarily tighter than 90: the key would seem to be a favorable enuf combination of that angle, the tilts of the two walls, the roughness of the rock, your strength, and of course what else you're holding onto. The tighter that angle, the easier for you to get both sides of the toe of the shoe, and the sole, to press tight enuf against the rock that the friction will hold you up.

Anyway, pp. 196-7 of the 6th edn. of Mountaineering: the Freedom of the Hills, published by The Mountaineers, has a couple of drawings and a single paragraph that communicates the def i gave & the details above to moderately experienced climbers.
--Jerzy•t 06:21, 26 November 2008 (UTC)

I was skeptical about this being "attestable", but usage at Google books convinced me otherwise. We just need a brief definition. DCDuring TALK 20:01, 10 December 2008 (UTC)