If casting into a silicone rubber mold, it is usually not necessary to use a mold release because of it's natural no-stick tendencies. If in doubt, Alumilite offers a Stoner Urethane Mold Release that will not only help release your part but will also extend the life of your mold. If you are pouring into molds that are not made of silicone, a thick layer paste wax or Stoner is required. If you use a mold release, you may need to wash your parts prior to painting in order for the paint to stick. Alumilite's UMR mold release is a dry film release used for separating silicone to silicone, urethane to urethane or urethane from silicone. It is not as effective as a mold life extender as the Stoner but can be used between multiple materials as where the Stoner is used primarily for releasing urethanes from a mold.