So, for the longest time I've been using old Chessex paint pots with washers glued to them for work holding. The figures all have magnets in their bases, so they generally stick to the tops quite well. Unless they're really large. Or metal. Or both.
So I wanted something that would physically clamp a figure, but still have the size and shape of the old pots I was used to.
Yes. Chessex used to make paint. Yes. I'm old. I also have large hands.
Several revisions later.... we have this. Spookums for scale.
It uses a 35mm M3 round head bolt and nut to clamp the two sides together with a marble as a hinge. Well, actually mine has the
CV joint bearing out of an '89 VW Fox as I didn't have any marbles, but it should be the right size for a normal 5/8ths marble. I actually kind of like the extra heft the metal bearing gives the clamp, but I realize not everyone has those just laying around. The screws on top are #6 x 1/2 wood screws (M3.5 x 12). The hole for the nut is tapered so after the first time you tighten it down it should hold it in place. Adding two small pieces of rubber sheeting (cut from an old rubber band) to the holes for the marble keep it all from moving after tightening.
Right now it will only hold 25mm round and square bases, but I had an idea last night for new version that will hold a larger variety.
EDIT:
I knew I forgot something - here is a link to the thing in case you want to make one of your own.