The sculpture is laid on a bed of clay and a mould of silicon rubber is created. With larger sculptures the rubber is applied directly in sections before a rigid fibre glass jacket is applied on top creating multiple pieces for casting.
Wax is meticulously painted into the details of the mould in many layers of hot wax. The mould is then assembled and slushed with wax to create an exact hollow replica of the sculpture. The wax is then fitted with sprues that allow the bronze to flow in during casting and the air to flow out.
Over the next five days, the wax is covered with multiple layers of ceramic shell to make a strong white investment. Pins and wires are also added for extra support to the shell.
The ceramic shell is then fired. The wax melts away from the inside of the shell leaving a negative space, for the bronze to be poured in to. In the foundry, the bronze is heated to 1200ºC and then carefully poured into the investments.
The ceramic shell is broken away from the casting to reveal the bronze. This is then ‘finished’ by craftmen using metal-working tools. Sculptures that are cast in pieces are welded together and fine detail is added where the sprues once were to create a finished raw bronze that shows no sign of the casting process it has been through.
The final colouration is then applied to the bronze, using heat and chemicals for different patina effects.