Combining Two Different Plastic Materials by Overmolding

Overmolding is a very useful plastic injection molding process for producing multi-material parts with some unique functional and cosmetic properties.

For example, overmolding can be used to add features of a different material to a handle or grip. Think of a power tool with grip pads made out of a softer, “grippier” material than the body of the handle. Or a gaming controller with some features made of a different material than the main controller body.

We overmolded the tire showroom display, pictured, for a customer. The “rubber tread” material was overmolded over the harder, blue plastic (substrate) piece that represents “water.”

Overmolding is not without its limitations. One consideration is that the two materials must be compatible, chemically and thermally.

Overmolding is not as straightforward a process as injection molding a part out of a single material, but it is something we are very experienced at. In our 16 years of injection molding, we’ve completed many challenging overmolding projects for our customers.

Feel free to contact us and talk to a project engineer about your next overmolding project.