Injection Molding in Action: Precision Rubber Overmolding at Shinzoft

Overmolding mold design — solving holding issues with nitrogen gas springs. In overmolding, the first part doesn’t always sit flat. On complex inserts, rigid clamping alone often isn’t enough. In this mold, nitrogen gas springs are added to apply controlled, consistent holding force. They help keep the insert fully seated during the second shot, without forcing the part or overloading the tool. Details like this often decide whether an overmolding process stays stable in production. Happy to exc