I'm designing my next project: a 90°, double acting, two piston steam engine with a ø1¼ inch diameter piston and a 1 inch stroke. I wanted an oversquare engine for a higher speed because torque won't be that important. The purpose of this engine is to power a home built Spin Art machine for the 2019 Maker Faire season. As I've done with my last steam engine, I plan on casting many components myself. I was thinking about lost foam casting. I like the process, but my skills cutting with a hot wire cutter are rudimentary at best. So I had an idea: Could a 3D printer be used to create a mold to make the lost foam pattern? The process would be as follows. The 3D printed clamshell would be assembled and insulation gap filling foam sprayed into the mold. After the foam is hardened, split the clamshell. The pattern would then be cleaned up and sprues glued on. Casting would be like any other lost foam process. I think my idea is sound except what should I use for a mold release to keep the foam from sticking to the mold. Has anyone any insights they would like to divulge? Thanks, ...Ved.