Vise on drum

just purchased 5 inch vise from Harbor freight, cheap vise better than no vise. Question is I usually mount vise on stand to a large truck brake drum, since I do not have said drum, will a 15 inch rim work as well? Not sure if rim has enough base weight to hold vise upright. Normally used for welding 1 in square tubing, fencing, nothing over 50 lbs. It is nice to have it moveable and not take up bench space.