Making a Positive Mould
1. Fill any holes in the Alginate cast, such as nostrils and mouth.
2. Mix a bowl of plaster.
3. Paint in a layer of plaster, making sure there are no air bubbles.
4. Build up the mould with layers of plaster to about one and a half inches and allow to dry thoroughly.
5. Peel off the Alginate and clean the mould.
6. Put the positive face cast on a board rubbed with petroleum jelly, ready to set it in a plaster base.
7. Build a frame round the board using wooden slats.
8. Raise the cast an inch or two with clay and fill the frame with plaster, encasing the edge of the cast.
9. When set, remove the slats. You should have a good smooth mould to work with.
10. With a drill, make two or three dents or chips ...
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