Lost Wax Method for casting Bronze Sculptures
The Lost Wax or Cire-Perdue Process used to make bronze sculpturesThe lost wax method is the traditional method of bronze sculpture casting. This Lost wax method is sometimes referred to as the Cire-Perdue Process. The Lost wax method has been around for at least 5000 years and was used by the early Egyptians, Greeks, Africans and Italians to make bronze sculptures and statues.
The Lost Wax Method is complicated and difficult process, it includes the following steps:1. A sculpture is created over an statue or sculpture made out of clay or plaster.2. A flexible rubber mold is made of the sculpture.3. The original clay or plaster is removed from this mold and the mold is cleaned out thoroughly.4. The mold is fastened together and wax is poured inside.5. The mold is removed and the seams and any casting imperfections are cleaned and repaired up by the artist or his associates.6. Wax vents or sprues are attached to the sculpture so that the molten bronze can eventually be poured into the piece and gases are allowed to escape.7. The molted piece called an investment is strengthened by making a mold of plaster mixed with grog around the wax casting.8. The investment mold is placed in an oven to melt the wax out and dry the mold.9. Bronze, which is an alloy consisting mostly of copper with small amounts of zinc, tin and lead, is melted in a crucible to a temperature of approximately 2000 degrees and poured into the warmed investment mold.10. After cooling, the investment mold is tapped or broken off gently and the sprues and vents, which are now bronze, are removed and chased.11. The piece is sandblasted and or sanded and reworked to clean the surface of the bronze from scaling , acids and oils which were a part of the casting process.12. A patina is often applied to the surface. This is a chemical process that is etched into the surface of the bronze that brings out the detain in the bronze sculpture.