Once cast, plaster is easy to paint, trim and sand. Plaster of Paris is white, so if you paint it and it chips, the white will show. However, adding tempera or fluid acrylics to the plaster when you are mixing it with water will create a colored plaster. Sealing with GAC 800 or resin will also prevent chipping.
Mix the plaster according to the manufacturer’s instructions. If adding tempera paints or acrylics, add cool water, as it slows down the setup time and allows you time to mix the plaster well. After the plaster has cured, put any removed clay into a plastic bag with a little water so you can reuse it later.
STEP ONE: Pour plaster of Paris into the clay mold. Then wait at least 30 minutes. You might place aluminum foil underneath in case of leaks.
STEP TWO: Pull away the clay walls once the plaster has hardened.
STEP THREE: Peel the clay off to reveal the richly textured plaster cast.
If the edges of your piece are not straight or smooth, you can sand them with a Dremel tool, a band saw, sandpaper or even your concrete driveway. Anything that works, right?
