The vise is bolted to my workbench. I shut the vise to about the middle of the expansion range and bounce it a few times with the hammer. A long time ago, Andy Kirkapatrick wrote about using 3mm, 4mm, 5mm cord to get familiar with what various shock loads "felt" like. If you blow up a loop of 3mm cord, it is about 1.5 kN of applied force, give or take a bit. A loop of 4mm cord is about 3.5 kN of applied force, and a loop of 5mm cord is about 5.5 kN of force. This depends a great deal on which cord, what condition, and how it is loaded, but I would like for my cams to absorb at least a good 3-5 kN without any trouble, so perhaps a better strategy would be to sacrifice a roll of 5mm cord and test all of the Aliens in my possession to hold 5kN. If I am going to do that, I suppose another fix-it would be to put a groove into a piece of leftover slate tile (I have a bunch from re-tiling our kitchen floor) and bolt the vise to a beam for a few hours, using that for the jaws. It's a lot more realistic, and easier to funk. Bounce, bounce, snap. Either the loop breaks at rated strength or the cam doesn't. Some of my aliens should probably be retired anyways, they look like shit and the heads are quite sticky. But none of them failed on my unscientific funking expedition last year, and god knows I'm not going to buy new ones.
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