How to Make a Sculpture Mold. Sculpture molds make it easy to reproduce a sculpture as many times as it is needed. The 2-part mold making process is one of several methods of making a mold.
Things You'll Need
- Sculpture model
- 10-gauge coated electrical wire
- Pallet board
- Foam board
- Release agent
Simplify your model by removing any extra or awkward parts. For instance, if your sculpture of a horse is mounted on a base, you will need to remove it. You can make a separate mold for the extra parts.
Cut some clay half an inch thick and roll it out on a pallet board. Place your sculpture on the clay sideways.
Use small balls of clay to fill up any gaps in the sculpture. Push some more balls of clay around the sculpture until you get up to the halfway point. Smoothen the clay out all around your sculpture with your fingers.
Select a point on the clay, about half an inch away from the model, and cut a groove in. You will need to cut this groove in the second half of the mold also for alignment.
Choose a point in the mold for the fill hole. Choose this point carefully to avoid future complications. For instance, a fill hole above the face of the model will create a blemish that you will have to file off every sculpture you make from the mold.
Use 10-gauge plastic-coated wire to create vents in the mold. Embed each one halfway into the mold.
Create a funnel for the fill hole from the edge of the clay mold to the sculpture. The fill hole is what you will use to pour the casting material into the mold.
Cut the clay around your model so that there is no more than three-quarters of an inch of clay around it. Place a foam board around the clay and make sure that it is at least half an inch higher than the highest point of your sculpture. Glue the foam board to the pallet and then press the clay against it to keep the mold air tight.
Apply a release agent to the mold and model. Mix some rubber and pour it into the mold slowly to prevent air bubbles from forming.
Remove the foam board and clay when the rubber has cured. Wipe the model clean of any clay in preparation for making the second half of the mold. Replace the wires.
Replace the foam board around the mold. Apply a release agent to the mold and model and then place supporting braces on top of the foam board.
Mix rubber and pour into the mold. Remove the foam walls when the rubber cures and separate the 2 halves of the mold.
Read "Mold Making, Casting and Patina" by Bruner F. Barrie to learn more about how to make a sculpture mold (see Resources below).