Mar 26, 2020 · Plaster of Paris is made with the combination of warm water and calcium sulphate hemihydrate. The main ingredient in homemade plaster of Paris is still water, but substitute in flour instead of calcium sulphate hemihydrate. Warm 2 cups of water and slowly stir in 3 cups of white all-purpose flour.
Most plaster primers are able to seal the surface with just one coat and you’ll just have to leave the surface to cure for about 24 hours before applying the paint. Step 3 – Paint the surface Depending on the characteristics of the paint, you can apply it either with a brush, roller or sprayer.