Simple parametric clip to attach the glass plate to the heated bed of a Reprap printer. You probably need to customize and tweak this if you want to use it, see the instructions tab.
Instructions
Measure your plate thickness, PCB + glass plate and choose a 'gap' width that is a few tenths of a mm smaller (you may have to tweak a bit before printing in bulk).
Measure the distance from the rim of the build plate to the rim of the glass plate (the 'border') and from that decide what the values of 'l1' and 'l2' should be. The 'depth' of the clip will be l1 + l2. An overlap of about 3mm works for me, so if l1+l2 > border + 3, you should be fine.
A clip width of 10mm works for me. If you make it too small, the clip may twist off.