Overmolding silicone onto silicone is normally the easiest silicone overmolding process to perform of all. This process is often referred to as two shot silicone molding. Existing silicone parts will have no difficulty with the temperatures necessary to process the second shot of liquid silicone. As long as the silicone substrate is clean, the new liquid silicone will normally want to bond to it without the need of primers, adhesion promoters, or plasma treatment. Lastly, if the first silicone part has not been allowed to fully crosslink (no postbaking until both components are in place)then the bonded liquid silicone overmolding strength will be even better.