Thanks Wes. The weight and pulley has no pulley, just a couple wraps of the rope around the low speed shaft, wrapped to give more drag on opening. Unfortunately it isn't enough for tight clamping and I had to add a ratchet. Still the leather jaws make light clamping adequate for most work. BTW the jaws open 44", which allows me to hold a drawer. Just have to lift the jaw to disengage the gear teeth for fast opening.