Bronze is an incredibly difficult (and expensive!) medium to produce. It requires multiple casts of plaster, wax, and clay, before even seeing the final piece. Our bronze sculptor, Copper Tritscheller, has been working with this medium for over a decade. Here are the steps she takes to produce a single edition of her sculptures.
First, Copper sculpts the animal she wants to create, creating a model out of clay or plaster. Once the model is finished, it is sent to the foundry and encased in rubber and plaster.
When this layer dries, the entire mold is cut in half and the original plaster model is removed. She carefully puts the mold back together including an access hole at the top or bottom of the mold.
Hot wax is then poured inside the mold to line the edges and cover the interior. When the wax is cool and solid, the rubber/plaster part of the mold is removed and the wax is dipped into a ceramic shell and coated with concrete. This mold is what is actually used for the bronze casting.
When this mold is dry, it is put into an oven and the wax melts out of the interior. This step gives the process its name: the “lost wax” process.
The bronze is finally poured into the mold and coats the interior of the shell, creating a hollow sculpture. When the bronze is settled and cool, the shell is hammered off. If Copper is making editions, at this time the foundry will try to salvage the shell so that they can reuse it to make more sculptures. If the work is “unique” (meaning Copper will only produce one bronze from the mold) then the mold is destroyed.
At this point, the sculpture comes back to Copper’s studio. If she wishes to add coloring to the bronze, she adds a patina. This can be a paint applied to the surface (like titanium for the large “Wading Bird”) or an acid wash that reacts with the surface to create greens or different browns.
The final layer is a thin coat of wax that protects the statue for many years to come!
Have more questions about the bronze process, or the works of Copper Tritscheller? Text or call us at 714.519.6297 or send us an email.