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How to Cast an RTV mold

This animation shows the various steps taken when creating an RTV mold. First, risers are put on the part to allow air to escape from the final mold. A thin film is attached to the part, which will act as a seam for the final mold. A box is built around the entire structure, and it is filled with silicone rubber. Once the rubber has cured, the box and risers are removed, the mold is opened at its seam, and the original part is removed. Any type of urethane can now be injected in the mold to create an exact duplicate of the original. Watch this quick video sculpting tutorial and learn how to cast an RTV mold.

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