Mold Star is available in different degrees of pot life, meaning the amount of time it takes before the mixed solution sets. Mold Star 16 has a shorter pot life and quicker curing time than Mold Star 15 and is the rubber we prefer using. For large area with more volume of rubber we add another Reynolds product, Slo-Jo that slows the curing time. As the silicone rubber is curing and especially for larger dense molds there is a tendency for gas pockets to form. The pockets may not be visible but when wax is subsequently poured into the silicone mold the pockets will create small holes in the wax. To prevent this, we place the thoroughly mixed silicone into a vacuum chamber and pump out the air and gases that form and when the remaining bubbles are extremely small, we then pour the solution over our pattern to create the mold.