This is a fine grade of 325 mesh the correct fineness for cold casting. Porcelain powder or other stone-based powders are added to polyester resin, polyurethane resin, epoxy, gypsum cement or other binders. Small objects are cast and cured in suitable molds. To conserve powderl when casting large pieces you can dust (salt) the mold surface, brush a thin coating on the surface, spread or roll the metal on or spray a thin coating. The mold is then back-filled with resin or fiberglass, iron or steel shot, sand or calcium carbonate to increase the weight to give it the heft and feel of a hot foundry ‘pour.’
You can also lighten the piece by added hollow glass beads to your back up casting mix. After curing and removal from the mold the object must be gently abraded or burnished with fine steel wool (triple 0 grade), a pad, or sand blasted to remove the microscopic film of binder from the surface of the porcelain powder particles.
The object will have the authentic look and feel of a true porcelain powder. That is because the surface is now true porcelain powder.
This article comes from artmolds edit released