Work-Intensive Bronze Casting Process

The Casting Process and History

 

Ancient “lost-wax” bronze castings have stood for centuries. Bronze casting is basically the same as it was in 2,000 B.C.

Bronze is an alloy of 95% copper, 4% silicon and 1% manganese with other trace elements such as iron. Silicon bronze was developed in the 1920s and has become the bronze of choice for fine art castings. It is strong, resilient, weldable and corrosion resistant. Hot-cast bronze, using the lost wax method involves many labor intensive steps.

It takes approximately two months to produce a finished bronze from one of Wayne’s clay sculptures.

With a sculptor’s eye, Wayne begins a project by rough sculpting a clay version of the piece, rather than sketching it on paper. Wayne feels that what works in flat art doesn’t always work in 3D.

When he has finished his early visual model, he begins sculpting the full size piece. The sculpting process can take up to six months. Wayne uses an oil based clay which remains malleable for the entire process.

Once the clay sculpture is completed, it goes to the foundry, usually with Wayne driving it in a refrigerated trailer. Wayne works with four foundries, each with its own specialty.

At the foundry, a latex mold is made by placing the sculpture or sections of it into a large form and pour latex around it. Once hard, the latex form is cut open and the original clay is removed.

Foundry workers then apply a hard plaster shell to support the latex mold after which hot wax is poured inside and allowed to harden. At this point the latex mold is removed leaving the detailed wax figure. The wax is now coated with a ceramic solution and dusted with sand, then hung to dry. This last process is repeated for the next seven days.

At this point the hardened shell is placed inside a kiln and fired to 2500 degrees. The wax melts and drains out of the shell leaving a hollow mold with all details intact from the original clay sculpture. While still hot, molten bronze is poured into this shell.

The shell is now cooled and the bronze hardens. The thick ceramic shell is broken off by skilled workers leaving the bronze statue which is then cleaned and sandblasted. The larger sculptures require separately cast pieces to be welded together with a team of workers called toolers smoothing the welds and any imperfections left during the casting process.

Foundry workers, themselves artists, apply patinas and colorations as requested by the artist. Chemical pigments are artfully applied using heat.

Wayne gives great credit to skilled foundry workers who artistically work through several steps to provide a beautiful piece of art.