| 09 November 2009
Mould Making
The first process a sculpture has to go through is the making of a rubber mould. A master mould enables hollow wax casts to be made in order to reproduce an edition of bronzes. A void has to be created around the head. The mould may have to be made in several sections, depending on the complexity of the original, to avoid undercuts.
Making Wax Copies
To make a wax cast, molten wax is painted into the rubber mould, taking care not to trap any air pockets in the surface and is gradually built up to an even thickness. After trimming any excess from the edges, the sections of the mould are assembled and through an aperture made for the purpose, cooling molten wax is poured in and then out of the mould. This leaves a thin deposit of wax three to six millimetres thick which unites the previously separate sections of wax. Once cool, the mould is opened and the flexible rubber peeled off the wax to reveal a perfect reproduction of the original sculpture. The thickens of the wax will determine the thickness of the bronze.
Investing the Wax