Mar 7, 2012, 1:10 PM
Registered: Jun 27, 2006
Are there concerns about the multiplication of force when using something as short as a quick draw to clip in (particularly if the bolts are spaced far apart)? The angle of the "V" created when clipping into TR bolts has a lot to do with how much the force is multiplied on each bolt when the system is loaded. Are the fall factors when TR'ing negligible enough for this to not be an issue?
In most 2-bolt bolted anchors, the two bolts are no more than a foot apart. Assuming that each quickdraw is about 12 inches (which is pretty short), the V angle is ~60 degrees, which translates into the force on each anchor being ~15% greater than the pulling force.
In reality, on many sport climbs there would be quicklinks or chains on the bolted anchors, so the V angle is quite a bit less than 60degrees even with 12 inch quickdraws.
Not a big deal in TR situation. And of course you can further improve things by using longer quickdraws at your anchor point, if you are concerned.
(This post was edited by lena_chita on Mar 7, 2012, 1:11 PM)