Mould Production Part 1
Mould Production Master mould production.
Master moulds are the first step to the production of metal miniatures. they are designed to give perfect reproductions of original sculpts. Normally master-moulds are made from industrial grade organic silicone rubber which is cut into shape to protect the original as much as is needed. Organic rubber needs to be vulcanised, this is the process of adding heat and pressure to harden the rubber to its finished state, but original sculpts need to be strong enough to resist these stresses. In conjunction with a skilled mouldmaker most sculpts are able to withstand these forces and should mould perfectly. Master-moulds can vary in size as suits the needs of the customer. Most Master-moulds are 228mm (9") diameter which gives enough space for 8 - 12 carefully placed miniatures. It is recommended that master-moulds are cast as little as possible. Once a mould has been heated it starts to wear. Undercuts may be lost at any time without careful mould handling, small amounts of the oils in the compound are lost and the mould starts to become dry and brittle. Once a master-mould is damaged little can be done to restore it. Master-moulds are used to make Master-castings; these first generation castings are the best that come from your original miniature.
Next time we move on to production moulds.