The “Lost Wax Method” of Casting Bronze.
The “lost wax method” is the oldest way of casting bronze known to mankind. Although modern
technology has contributed some refinements to ensure more uniform quality, this technique has
remained essentially unchanged for some 6000 years.
- A flexible rubber mold is made from the original sculpture.
- A positive wax model is made by pouring hot wax into the mold.
- When cool, the wax is removed from the mold and detailed.
- The wax model is then submerged in a special foundry plaster or stuccoed
with layers of sand to produce a ceramic shell of sufficient strength to
withstand the weight of the molten bronze.
- The wax is then melted out of the shell; thus, the term “lost wax method”.
- The molten bronze is then poured into the ceramic shell and left to cool.
- When the shell is chipped away, the raw bronze casting is revealed.
- The bronze is then sandblasted and “chased”, or finished using metal
- Finally, the surface of the bronze is patinated; a process using chemicals
and heat to achieve the desired finish.
- A hot wax finish is then applied to ensure a beautiful lustrous patina.