Tried to do a paper mold, prison chess-style.

If anyone is interested, previous two molds and new version below were done with Up Plus. (No information on the blue one.)
New version, customized with a “tramp stamp”, which serves as both an outside ornament and part of the sand-pressing form:


How it worked:
(This print had almost legible writing, but no head.)
This one was pretty okay, considering the sand quality.

