This is a great visual of the molding of silicone rubber. Think of the compression mold as a giant waffle maker. The top and bottom half compress a carefully cut and weighed portion of silicone material. Once the mold is preheated to the correct temperature, the mold is then closed under extreme pressure (150 - 250 tons).
During the molding and compression time, when the tool is closed, the silicone fills up the entire mold cavity and is then vulcanized.
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