How thick should a plywood workbench top be?
How thick should Workbench steel be?
How thick should a bench board be?
Should a workbench have an overhang?
Determine how much overhang you need to accommodate the end vise, usually somewhere between 13” and 20”. Use the same overhang on both ends of the bench and you are pretty much done. Because of the thick top of the French bench, the cantilever isn’t a problem.