I made a wide wire cutter to cut styrofoam that is used on the bottom of solid surface shower pans. Corian, Staron, HI-MACS, Livingstone and Stonia shower pans are thermoformed on the bottom. The gap is filled with foam to create a solid floor that lays flat on the subfloor.
A FabNet member has detailed the complete fabrication of a Corian shower surround including cove walls, seat and soap caddies. You will be amazed at the attention to detail and craftsmanship involved.