The materials I work in are wax, clay or most often plasticine.
The sculpture is built up on a wire armature and worked on until I am happy with the result.
The sculpture is then moulded in rubber; a two piece mould supported by a plaster or fibreglass ‘jacket’.
The inside of the mould is a space or ‘negative’ impression of the original sculpture. By pouring molten wax into this mould, which is allowed to harden, a hollow wax impression of the original is made. At this stage the wax is usually checked and worked on by the artist. A system of ‘runners and risers’ is made around the wax sculpture. This, in the later stages of the process, will enable the molten bronze to flow quickly to all the parts of the sculpture and allow the air to escape.
The whole wax ‘structure’ is now dipped in a runny ceramic material.
As that dries the process is repeated again and again until you have something which looks like a lump of clay, the wax impression being inside. This ‘mould’ is baked, and the wax inside burns out (hence the name, the lost wax process) leaving a cavity where the sculpture was. It is into this that the molten bronze is poured.