I just drop a ruler on and draw a line with a sharp pencil. Nothing to it. It is 10mm underfloor insulation sheet ... £4:20 a sheet and a couple of sheets would build you a huge dungeon. Got mine here:cornixt wrote:How do you make such clean cuts through the foam to make the edges of each square, and what sort of foam is that?
http://www.ebay.co.uk/itm/10mm-UNDERFLO ... SwT6pVhrgn
Easiest stuff to work with ... and cheap as chips .... can't believe I have put this off for so long.