In the prior working method post you saw how to make a clay positive. This post expands on the versatility of mold making process . Option 1 you can create a single use plaster/silica investment mold and hand build or coddle pour a refractory mold. In option 2 you can make a pure plaster mold to help speed the working time from clay building hundreds of clay original models and instead use a silicone positive. This requires you to make a pure plaster mold and let it dry 24 hours. Then you can pour silicone into the plaster mold negative which then once cured (24-48 hours at 70 degrees) you have a silicone positive. Using a coddle you then make a #1 pottery plaster/200mesh silica investment mold. 1:1:1 or 1 part #1 pottery plaster added to 200 mesh silica and Water by weight. Using a silicone negative lets me reduce the time spent to get color samples for my art. This approach works well for thin pieces but the thicker the artwork gets the color become quite dense. The principle remains the same but the clay forms can change to allow for the direction work and the thickness of the piece and light you want to transmit.
