Creative Mechanisms has a process that enables us to develop a prototype of an overmolded part. An overmolded part is made when by injection molding a soft material around another part. The other part can be anything that can be inside the injection molded tool. Most often it is another injection molded plastic part or a purchased or manufactured metal part. This other part is inserted in an injection mold tool and a softer material is molded around it. It does not have to be molded completely around the part. It could only be over a section of the part if desired.

When we prototype an overmolded part we follow a process very similar process to that of the injection molded production part. We essentially prototype injection molds. We start by CNC cutting a mold out of Polycarbonate plastic. We then produce the substrate and insert it into the mold. The low durometer material is then injected into the mold. For a prototype this is done by using a large syringe and injecting the material into the back of the mold.

See how it's done in this behind the scenes video of the Creative Mechanisms process for creating a prototype of an injection molded overmold part: