Removing a silicone-based release agent from your cured urethane casting is not easy. The most effective way is to sand blast or bead blast the surface of your casting. Sand blasting, however, removes a micro thin layer of the casting’s surface. If not done properly, you can damage or remove fine detail.
Soap – Wipe or brush the casting with a soap that has high alkali content. Cascade™ brand dishwashing gel is highly alkaline and also contains baking soda, which is an advantage.
Solvents – Wipe or brush the casting with Acetone, Toluene, Isopropyl Alcohol or Mineral Spirits. Important; follow all safety precautions when using flammable liquids.
You can then prime and paint your casting.
Stop – There Is A Better Way.
If your goal is to paint your casting after demold, consult FAQ – Painting A Finished Casting.