I produce a lot of industrial castings during the year. The "resins"
(urethanes) I use are high-grade, industrial-quality with a very high heat
tolerance. The cured casting has physical properties between styrene and
ABS. Vacuum casting fails miserably with these types of resins because they
kick over quickly and require heat and pressure to cure properly. Without
pressure, the end result looks like Swiss cheese, just with smaller holes.
Pressure works for 1-pc bodies and flat castings but, like anything else, ya
gotta know how the process it all . and that's proprietary.
Smoky Mountain Model Works, Inc.
Ph. (828) 777-5619