Needless to say I have never done one, hence the question.
The only time I've had to do it was a Yosemite offwidth. This involved laying away off a 'flat hand' and stacking the other one balled up into a fist, against the flat hand. To move up a knee was wedged in the crack, then the fist taken out and layed away on, to enable me to take out the flat hand and place it as a fist against the other hand.
Hope that makes sense.
Definitely above fists. You resort to stacking because you've run out of one handed options, stuff involving both hands is way harder because taking one out can be tricky.
True that, maybe I just need to suck less but I find myself with both hands tied up and in "now what?" situations every time I've stacked my hands.
They come in varieties ranging from hand-hand to fist-fist. Here is what Craig Luebben and John Long say in "Asvanced Rock Climbing":
"Hand stacks perform well in the 3 1/2 to 6 1/2 inch range regardless of the angle or difficulty. The tricky part is suspending our weight whiole moving both hands up.
"We set a solid hand-stack as whigh as we can comfortably reach. Next we lean out off the stack and set a knee-jam high in the crack ... most of our weight shoukld remain on the knee-jam. After locking the legs, we move the stack up, and repeat. If our knee won't fit in the crack we're buggered.
"... perhaps the most technical maneuver in all of climbing, and takes some doing to understans, let alone to perform efficiently."
The theory is a lot easier than the practice! On less steep cracks the technique can help to avoid the usual ungraceful thrash.
> Next we lean out off the stack and set a knee-jam high in the crack ... most of our weight should remain on the knee-jam. After locking the legs, we move the stack up, and repeat. If our knee won't fit in the crack we're buggered.
How does a kneejam work? Stick it in leg-straight, and then bend it? Knee doesn't seem to give as much range as hands do, so I guess the "buggered" option is quite common...
Do it right and you can get a no hands rest on a 15 degree overhang. e.g. : http://www.ukclimbing.com/images/dbpage.html?id=122457
> Do it right and you can get a no hands rest on a 15 degree overhang. e.g. : http://www.ukclimbing.com/images/dbpage.html?id=122457
This description misses the most critical aspect of the knee lock, which is the toe cam on the outside of the crack. You don't "tense your quad" to lock the knee in. The correct technique was described, in 1988, by its inventor, Randy Leavitt, with far more clarity than any subsequent description. Read http://www.youtube.com/watch?v=gWXMPYlBQ3o .
If the crack is too small for a knee (double hand jams rather than hand jam against fist), then the dreaded calf-lock is called for. See http://www.climbing.com/skill/the-calf-lock/ for the details.
The Wild Country Crack School video recommended above is not much use. It describes all the upper body jams first, without explaining how they are paired with lower-body motions. When it finally gets around to the feet, the only technique described is the heel-toe jam, which typically goes with arm-barring and chicken-winging and will usually not be available for hand-stacking widths. Since knee and calf locks are never mentioned, the viewer is left in the dark about how hand stacks are moved up. The links given above will be far more helpful.
It's so long since I've done one I can't remember what I do with my foot, but it seemed solid so I probably did cam it somehow.
One of my local crags is the home of Thai Boxing, so I should really get re-acquainted with WIDE sometime soon.
Reading his discription of the knee lock, I'm pretty sure that's what I was doing.
my crack machine is almost complete with a range of sizes! Will use your leavitt vid for sure on my 30 degree handfist 10cm crack.
could thius visit coincide with me coming home?
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