A derivative of the PCB Gator Vise and Hobby Clamps http://www.thingiverse.com/thing:12616
This one has been modified so that it will print on a TOM and will hold circuit boards in such a way that you have better access to the edges of the board.
Clean your platform well then print it. Acetone (nail polish remover) works very well.
I use 1 extra shell and 50% infill.
Obtain a "Helping Hands" from HF or other source and replace one of the alligator clips with the PCB Vise.
Wedge2 is the standard size. Both smaller and larger wedges are included in case your tolerances are different than mine.