An auto body primer is applied, followed by an acrylic paint and finally an acrylic sealer. The major advantage to powder coating is that there is no release agent to remove when the casting comes out of the mold. Models can be immediately primed and painted. The labor and time savings realized by employing this technique is significant. Excess powder is blown away.
Finished castings have paint-ready surface.
There are different techniques used to achieve a metallic finish with a urethane resin. Different metal powders such as bronze, brass, aluminum, nickel-silver and copper can be used depending on the effect desired. To make a cold-casting, metal powder is mixed into the resin, until the mixture is thick and creamy. The remaining cavity is then filled with plain resin, resin mixed with a different filler to give the casting body and dimensional stability, or foam. Metallic powders are available from most Smooth-On distributors.