Massive workbench vice
Paul M in San Diego
>Hi everyone,
In light of the recent long discussion about workbench vices and jaw racking, I was interested to see that there is a long workbench article in the latest "Woodwork" magazine. The tail vice is a monster with 1" guide bars and a single acme screw in the center. The author had this vice custom made by anchoring the guidebar bushings and screw nut to a large metal plate that covers the entire underside of the bench.
For reference, my current face vice is the typical one without a rear jaw and with a cast plate that contains the bushings for the two guide bars and the screw nut. It racks like crazy. The author in this article has spaced the guide bars really far apart, and the bars are 3' long monsters so he could space the bushings really far apart fore and aft.
Would all this metal actually help prevent racking? My gut feeling is no it wouldn't. But it appears that he addressed this problem by screwing a large plate directly to the far end of the two guide rods (away from the jaw) so that there is a large surface of metal that must rack to allow the guide bars to shift independently. I wish I could describe this better. You probably need to see the diagram on the top of page 51 to visualize this.
The problem that my vice has is that the spot where the bars are anchored into the jaw are not solid, so the bars can rack off of the 90 degree angle protruding from the back of the jaw. It does have some metal for the front of the jaw, but the guide bars are not very secure on this jaw piece. The author just mounted the bars to the jaw with nuts (no metal parts of jaw), and instead made a much more beefy connection between bars on the other end of them.
The author makes no claims in the article regarding stability of jaw under offset clamping. But he seems to have over-engineered a monster way of getting around this problem. I just thought it was interesting to see another solution. Personally, I think I would rather have the LV twin-screw vice (which I should have bought the first time around).
