Bronze Casting Process - This is how I make my bronze sculptures
- A sculpture is made in clay or wax or some other media.
- If the sculpture is made in a medium other than wax, a mould of silicon or plaster (or a combination of the two) is made of the sculpture, then the sculpture is removed from the mould and wax is poured into the cavity.
- Any imperfections in the wax are touched up.
- A pouring vent and channels to allow the molten bronze to flow into the sculpture (called runners) are made of wax and attached to the wax sculpture. The pouring vent becomes the spout that the bronze is poured in through. Vents to let air escape from the mould (called risers) are also added to the wax.
- A ceramic mould is made of the wax. The ceramic mould has to be able to withstand having bronze poured into it at 1200 -1400 degrees celsius.
- The wax is melted out of the ceramic mould.
- Molten bronze is poured into the cavity of the ceramic mould.
- Once cool, the ceramic mould is cracked open to reveal the bronze.
- The runners and risers and the pouring vent are cut off.
- Grinders are used to remove and smooth excess metal.
- The sculpture is checked for imperfections such as small pin holes that may need filling in.
- A coloured patina (chemical colour) is painted on and fused onto the sculpture with heat.
- The finished bronze is signed with metal etching tools and polished.
Here is a link to a video I took of sculptures and some of the bronze casting process at the Asia Fine Arts Foundry in Attuhaya, Thailand: Bronze Casting in Attuhaya.