Quick sketch of hard clamping in the Veritas twin screw vise.

So, I mentioned about 2 weeks ago that I would put up pictures to describe what I was talking about, when I said that it was possible to use the vise to really crunch down on something. Rather than re-edit that post, I figured it would make sense to do it this way.

Step one:

Put the object to be held into the left side of the vise. (Or, the side that does NOT have the release pin on the handle.) Both screws will rotate inwards, as shown.

Step two: Pull the release pin. This will allow the handle on the right side to spin freely, while the left side still holds with regular clamping force.

Step three: Rotate the right handle as if to loosen the jaw on that side. Because of the way the vise is built, it will actually lever the right side of the jaw out, a little bit, pivoting around the left hand screw. The force it gets from using the length of the vise as a lever will really crunch down on whatever's being held in the opposite side of the vise.

This isn't always truly necessary, but once in a while you get an oddly shaped object that you have to saw through, or do something else that exerts a lot of force. When it comes to that, there's just no substitute for the application of fundamental physics.