How to Make a Plaster Moulding of a Body Part
- 1). Liberally apply a layer of petroleum jelly to the body part to be molded. The jelly will protect body hairs. Layer it on thickly or the mold will be painful to remove.
- 2). Mix the alginate with water with a whisk according to the manufacturer's instructions until it becomes semi-fluid. Alginate is a rubbery material that captures the fine details of a body part and forms the basis of your mold.
- 3). Spread the alginate onto the body part, applying the material in several layers. Wait three to eight minutes for it to set, depending on manufacturer's instructions.
- 4). Place three layers of plaster bandages over the alginate and wait for them to become firm, generally between between three and six minutes.
- 5). Carefully cut a slit through the mold using the scissors. Safety scissors will prevent you from cutting the body part.
- 6). Slowly remove the alginate. Ask your model to wiggle the body part slightly to aid in the removal.
- 7). Quickly apply strips of plaster bandages to the slit in the mold, closing it before the alginate begins to deform at the slit.
- 8). Fill the mold with plaster. For best results, use a high grade plaster intended for model creation, found at art supply stores. Allow the plaster to dry according to the manufacturer's instructions.
- 9). Remove the plaster bandages and the alginate, revealing the cast body part. If some pieces are difficult to remove, carefully cut them away using a razor knife.
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