Made this sign out of Gravoply 2 (from Engravers Depot, in Missisauga). Easy guys to deal with. Two color plastic, top layer is less than .1 mm thick. Just double-sided taped it down to my MDF table. By the way, Walmart sells a 'Scotch Permanent Double-Sided Tape' that works great for CNC'ing. Removes clean, holds well.
http://www.engraversdepot.ca/indoor-pla ... ply-2.html
Took about 9 hours to do. I should have used a 1/8" endmill to start and then finished it with the .1 mm 25 deg v-bit. But i did the whole job with the .1mm tip v-bit. 9 hours. Very clean, though:)
Note to self: my .6mm carbide endmill did not survive this material.