I made a moxon vice a while back. I clamp it to my bench with a couple of steel bench hold-downs. I made the slots for the threaded bolds about one and a half times as wide as the diameter of the bolts and that seems to allow sufficient movement for the front plate to be tightened unevenly if necessary.
The photos show the vice clamped with G-clamps as well, but I usually don't bother with them these days, the hold-downs are enough.
I used tulip wood for the internal faces (external one is lined with leather for good grip) and Keruing for the outsides. I inlaid brass plates where the clamping wheels press. Unnecessary, I know but it looks cool. It does show the slot size I used to give the threaded bars room to move.
The photos show the vice clamped with G-clamps as well, but I usually don't bother with them these days, the hold-downs are enough.
I used tulip wood for the internal faces (external one is lined with leather for good grip) and Keruing for the outsides. I inlaid brass plates where the clamping wheels press. Unnecessary, I know but it looks cool. It does show the slot size I used to give the threaded bars room to move.