How to Choose the Right Resin for Custom Injection Molding

Choosing the wrong resin is the #1 cause of injection-molded part failures. Start by listing your part's requirements: continuous operating temperature, impact resistance, chemical exposure, and surface finish.

For structural automotive clips, glass-filled PA66 offers stiffness and heat resistance up to 120°C. For optical parts, optical-grade PC delivers clarity but needs tight drying and a textured mold surface (VDI-27 or finer). Medical parts often require USP Class VI or ISO 10993 compliant grades and a cleanroom molding environment.

Always validate with a rapid-tooling prototype before committing to production tooling — it is far cheaper to change material at the 10–15 day prototype stage than after a 4-week steel tool is cut.