Jameel Abraham
06-08-2008, 6:56 PM
I'm building a couple leg vises for my German-style Roubo bench, and I'm running into some issues that I hope some with leg-vise experience can help me with.
I'm planning to make a rather thick chop for the leg vises. Somewhere between 2" and 3" and almost 8" wide. This means that the chop will be rather heavy. This chop must be supported by either the screw itself, or by the parallel guide at the bottom of the chop.
If I build the vise so it's hanging by the screw, the chop will get lower as the vise is opened, since the screw does not hang level with the weight of the chop hanging from it. In this configuration the parallel guide at the bottom is not supporting the weight of the chop, but is floating in it's mortise.
If I build the vise so the weight of the chop is bearing on the parallel guide, then when the vise is opened, the screw will be pulling on the upper portion of the chop (the screw is not bearing any weight--its basically floating in the chop's screw hole), creating a tilting action and wedging the parallel guide in its slot instead of pulling the parallel guide straight out.
I'm not familiar with the function of leg vises, since I've never used one. If anyone here has some ideas for me, or explanation, I'd love to hear from you. This the basic design I'm following for the leg vises. It's from Andres Roubo's book.
I'm planning to make a rather thick chop for the leg vises. Somewhere between 2" and 3" and almost 8" wide. This means that the chop will be rather heavy. This chop must be supported by either the screw itself, or by the parallel guide at the bottom of the chop.
If I build the vise so it's hanging by the screw, the chop will get lower as the vise is opened, since the screw does not hang level with the weight of the chop hanging from it. In this configuration the parallel guide at the bottom is not supporting the weight of the chop, but is floating in it's mortise.
If I build the vise so the weight of the chop is bearing on the parallel guide, then when the vise is opened, the screw will be pulling on the upper portion of the chop (the screw is not bearing any weight--its basically floating in the chop's screw hole), creating a tilting action and wedging the parallel guide in its slot instead of pulling the parallel guide straight out.
I'm not familiar with the function of leg vises, since I've never used one. If anyone here has some ideas for me, or explanation, I'd love to hear from you. This the basic design I'm following for the leg vises. It's from Andres Roubo's book.