We used a hot knife to cut the 2" foam into 24" x 32" blanks. Then I used my Samson 510 CNC table with a BOSCH EV1617 2.25HP router with a 60 degree V bit to carve the text. Then we used the hot knife again to shape them. We sprayed the text and the front and sides with flat black spray paint. The foam melted a bit from the paint, giving the stones some texture. Then I used the small diameter cabinet rollers with KILZ water base primer, tinted gray to lightly roll over the foam, hitting the high points. After that, some random flat black spray paint again from a distance, to give the stones an aged, neglected look. Each stone took about 40 minutes to make.
Joe
