Lost wax method
The process can take several weeks to several months to complete, depending on the size of the sculpture. The first step begins with the artist creating an original sculpture from wax, clay or plasticine.
The next step involves making the rubber mould-the most critical step. A flexible mould made from the original is used to create duplicates. Every single detail of the original must be captured at this phase.
Wax casting is the third step. Molten wax is poured into rubber moulds to from wax duplicates of the original. These are removed from the moulds and re-detailed by the artisan. Each is treated as if it were an original work of art.
The next step involves the addition of so-called ?wax networks?. Wax rods and a pouring cup are attached to the wax casting, acting as channels through which the molten bronze will flow into the sculpture.
The wax figure is coated with a liquid refectory ceramic. On the first dip a fine powder is applied; coarse sand on the next dip. This step is repeated to increase the coarseness of the material and to create the ceramic mould. The piece is then fired in a kiln. The shell is broken and the wax eliminated, leaving a cavity inside-thus the term ?lost wax?.
The ceramic mould is removed from the kiln and molten bronze is immediately poured into the shell. After the casting has cooled, the ceramic shell is carefully broken away, revealing the unfinished bronze sculpture.
Fragments of ceramic shells and other particles that adhere to the bronze are blasted off using air under pressure.
The artisan gives the final touches to the bronze by grinding, chasing, sanding, and polishing before welding all the pieces of the sculpture together.
The very last step is coloring. The bronze is treated with chemicals and heat to give it its chosen color.