ART: Sculpture. Plaster Casting. Query.

Has anyone had experience in plaster casting? This particular question
relates to casting a positive form within a negative wooden form. What is
needed is advise. How can one keep the positive from sticking to the
negative wooden form such that the wooden form and the plaster cast
will not be destroyed? We are planning to use a soap or vasaline coating
between wood and plaster. Also, we are planning to drill air holes through
the wooden form after hardening of plaster. The wooden forms are cut in
such a way that only three sides connect with any part of the plaster.

Is there any specific time to break the mold open after hardening of the
plaster? hat is,
That is, how long should (or could) one wait until breaking open the
wooden mold from the positive plaster casting?

If you know how, then send some information. If you have a friend who
knows, then just route this note to the friend.

We need to cast tomorrow! Thanks. Howard
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