Prosthetic makeup

Prosthetic makeup (also called Special make-up effects and FX prosthesis) is the process of using prosthetic sculpting, molding and casting techniques to create advanced cosmetic effects. Prosthetic makeup was revolutionized by John Chambers in such films as Planet of the Apes and Dick Smith in Little Big Man.

Technique

The process of creating a prosthetic appliance begins with lifecasting, the process of taking a mold of a body part (often the face) to use as a base for sculpting the prosthetic. Lifecast molds are made from prosthetic alginate or more recently, from skin-safe silicone rubber. This initial mold is relatively weak and flexible. A hard mother mold, typically made of plaster or fiberglass bandages is created overtop the initial mold to provide support.

Once a negative mold has been created, it is promptly filled with gypsum cement, most commonly a brand called "Ultracal-30", to make a "positive" mold. The form of the prosthetic is sculpted in clay on top of the positive. The edges of the clay should be made as thin as possible, for the clay is a stand-in for what will eventually be the prosthetic piece. Along the edges of the mold, "keys" or mold points are sculpted or carved into the lifecast, to make sure that the two pieces of the mold will fit together correctly. Once sculpting is completed, a second mold is made. This gives two or more pieces of a mold - a positive of the face, and one or more negative mold pieces of the face with prosthetic sculpted in. All clay is carefully removed and the prosthetic material is cast into the mold cavity. The prosthetic material can be foam latex, gelatin, silicone or other similar materials. The prosthetic is cured within the two part mold - thus creating the beginning of a makeup effect.