It is really important to have enough plaster bandages. Too few and your mold will distort and possibly collapse into a useless mess.
How to Figure
The bigger the mold the thicker the plaster bandage shell needs to be to keep the mold from distorting during the pouring up.
- For a face mold, 4 layers is sufficient
- For a head mold we need an average of about 5 layers
- For a half torso, we need about 5 layers
- For a full torso we need to have 6-8 layers of plaster bandages
A three-inch roll of plaster bandage contains 540 square inches of bandage (180 inches long x 3 inches wide)
- A typical face mold is a round bowl approximately 12 inches in diameter or about 115 square inches. Doing the math shows us that a face can be done with about 1 roll of 3 inch bandages. We include 1.5 rolls in our Face Casting Kit to be on the safe side.
- A head mold has a surface area of between 600 and 700 square inches. Because of that it requires about 7 rolls of 3-inch bandages
- A half torso mold is usually about 200 square inches. Calculations show that we need about 3 rolls of plaster bandages
- A full torso can be 400 square inches so we need between 6 and 8 rolls. Always better to err on the slightly thicker side for safety.