The base relief sculpture Creation of Life by Kirk Williams

A Base Relief Sculpture in the Modern Bronze Age

By Kirk Williams

In 2010, I was given a commission to do a base relief sculpture for the Pioneer Care Center, a new retirement home in Fergus Falls, Minnesota. The sculpture, called “Creation of Life” was to be mounted on a wall about 14′ off the floor. I knew I had to make it strong and lightweight. The method I used was to sculpt the design in oil based-clay on a large wooden easel. Then I covered the finished clay sculpture with several layers of clear silicone, occasionally adding cheesecloth for build-up and strength. When the silicone was thick enough, I built a mold cradle, made of plaster and gauze reinforced with heavy metal wire over the silicone. When the mold cradle had dried, I removed it and the silicone mold and laid them flat.

1.) Williams first created the base relief sculpture in clay on a wooden easel.

1.) Williams first created the base relief sculpture in clay on a wooden easel.

2.) Epoxy/bronze mixture was buttered into the silicone/plaster mold.

2.) Epoxy/bronze mixture was buttered into the silicone/plaster mold.

3.) The silicone mold was peeled from the base relief sculpture.

3.) The silicone mold was peeled from the base relief sculpture.

4.) Buffing the sculpture with steel wool exposed the bronze powder.

4.) Buffing the scuplture with steel wool exposed the bronze powder.

I made a mixture of 105/205 epoxy and added bronze powder until it was the consistency of chocolate frosting. 105/205 gives me enough time to mix and spread it into the mold, but sets up within about an hour, making it possible to start another application. The epoxy/bronze mixture was buttered into the mold by using two fingers (gloved) to an eggshell thin layer, to avoid any possibility of air bubbles. When this cured I built up reinforcement layers using epoxy mixed with chopped fiberglass and Christmas tree flocking. For additional reinforcing, I embedded heavy wire and small iron rods.

After the final epoxy application had cured, I attached the base relief sculpture to a wooden frame with wires embedded in the back of the sculpture. With the frame standing vertically I gently pulled the silicone mold from the sculpture. I trimmed the rough edges with a Dremel® tool. Buffing the surface with steel wool brought out the metal, and gave me control over the amount of contrast. Olive oil rubbed over the surface gave the sculpture a smooth patina.

The 8′ long sculpture weighs less than 150 lb and was lifted using a scissor lift and hung 14′ above the floor level with ease.

5. The completed base relief sculpture weighed only 150 lb and hangs 14' above the Care Center floor.

5. The completed base relief sculpture weighed only 150 lb and hangs 14′ above the Care Center floor.