Casting method where a form created with silica gel is burned twice to create favorable micro-cracks and minimize impurities. Beskrivning The process Two separate mold halves are made by filling two main shape with a mixture of silica and gel. The molds are vibrated to ensure that all voids are filled. When the mixture has solidified the mold is lifted out of the main shape and burned with a blowtorch to remove contaminants and to form micro-cracks in the surface of the mold. These cracks are desired as they allow gases to escape from the melt while the molten metal cannot penetrate the cracks. The arrangements is then fired once more in an oven to remove residual contaminants. The dies are then assembled to complete the form and cores are added if required. Thereafter, it is preheated before the mold is filled with molten metal, after the metal has solidified the part is freed from the mold. In cases where the part has a flat side one mold may be sufficient which greatly simplifies the process. Shaw Casting Process films
