Bronze art casting using the ancient lost wax process has been around for thousands of years. This labor intensive process takes several weeks from start to finish. Bronze is an alloy. It is a mixture of 95% copper, plus small amounts of tin, zinc, and silicon. The following includes a description of the procedure:
- The artist creates an original sculpture from either clay or wax.
- A rubber mold is made of the original sculpture by applying numerous coats of rubber over the original. After this is cured, it is removed. This new rubber mold will show every exact detail from the original. This mold is used to create duplicates of the original design.
- The rubber mold is filled with molten wax. After the wax cools, the rubber mold is removed from the wax. We now have a wax duplicate of the sculpture.
- The artists will hand-finish the wax to match the original.
- Wax rods and wax funnel are attached to the wax duplicate. This will alleviate the trapping of air and gas.
- The wax duplicate is coated with a liquid ceramic. This is done several times to create a stable mold. This is cured for a few days.
- The wax mold covered in ceramic is fired up in a kiln. The “burn-out” process bakes the shell and the wax melts out of the shell. This is where the “lost wax” name comes from.
- The ceramic shell is taken from the kiln and molten bronze is poured into the mold.
- After the bronze cools, the ceramic mold is carefully removed. We now have a bronze sculpture.
- The piece is now sandblasted and cleaned to remove any fragments.
- Artists will hand finish the bronze to look exactly like the original.
- Finally, chemicals, acids and heat are applied to get the desired patina. Wax is applied to the bronze for a protective finish.
