The lost wax process
The Lost Wax Casting Process: 12 Steps to the Perfect Bronze Statue
At the Randolph Rose collection we cast bronze statues using the traditional lost wax casting method. Bronze art casting using the ancient, lost wax process has been around for thousands of years.
This labor-intensive process takes several weeks and oftentimes months, from start to finish.
Bronze is an alloy. It is a mixture of about 85% copper, plus small amounts of tin, zinc, and silicon.
Lost Wax Casting Process
An artist creates an original sculpture from clay or wax. An exact replica will eventually be made into a bronze sculpture.
A rubber mold is made of the outside of the original model sculpture by applying multiple layers of liquid silicone rubber over the clay, which creates a flexible mold.
The Rubber Mold
Will show every exact detail from the original. It is coated in liquid fiberglass, which hardens into a supportive shell.
The hardened mold is removed from clay sculpture. Molten wax is poured into the mold.
Removal Of Wax
The wax cools and the mold is gently removed from the wax, leaving an exact wax replica of the original sculpture.
Wax rods and funnels are attached to the wax sculpture to 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.
The ceramic shell coated wax sculpture is fired up in a kiln. The “burnout” process bakes the shell and the wax melts out. This is where the term “Lost Wax” comes from. The inside is hollow and ready for the bronze.
Bronze is melted at 2,200 degrees Fahrenheit. The molten bronze is poured into the cured ceramic shell.
Removal Of Shell
After the bronze cools, the ceramic shell is carefully removed. We now have a bronze sculpture.
The sculpture is sandblasted and cleaned to remove any fragments. Artists will hand finish the bronze to look exactly like the original.
A patina is applied with heat to color the bronze. A coat of wax is then applied to protect and seal the finished sculpture.
View our recent custom sculptures