When the mold temperature is high, liquid silicone will have a low hot tear strength. If mold temperature parameter is permitted to be adjusted, lowering the mold temperature would make increase the tear strength, which could ease in degating the part. The disadvantage of the lower temperature mold would increase the cycle time .
Degating can be influenced by gate designs: type, size, and location. Direct gating is preferred over other types of gating; the nozzle directly feeds the material into the part or by using the cold deck. Since the nozzle keeps the silicone uncured, the gate can be easily degated. Smaller gating is commonly used to solve degating problem. The gate in injection molding silicone is smaller than in thermal plastics injection molding. Nevertheless, it is very important to make sure that the gate size must be large enough for the silicone to fill the cavity before the gate completely solidifies. Just like real estate, “location, location, location” is important in degating process. For instance, it would be more difficult to degate when the gate locates at a thin section of the part vs. thick section.
The parameters that are discussed above are considered as tips; there isn’t a standard or best way to approach degating solution. It really depends on case by case situation.
I hope this answers your question. If you have any other questions, please email me directly at firstname.lastname@example.org