What Is Overmoulding and When Is It Used?
A clear guide to overmoulding for product designers, engineers and manufacturing buyers.
Overmoulding is a moulding process where one material is moulded over another material or component to create a combined part. It is often used to add grip, sealing, cushioning, colour, protection, electrical insulation or improved ergonomics.
Introduction
A clear guide to overmoulding for product designers, engineers and manufacturing buyers.
What overmoulding means
Overmoulding creates a combined part by moulding one material over another material, insert or pre-formed component. The result can be a part with improved grip, soft-touch feel, sealing, protection, insulation or visual contrast.
When overmoulding is used
Overmoulding is used for handles, grips, buttons, seals, electrical parts, protective covers, ergonomic features and components that need more than one material property. It can improve product feel and function without separate fasteners.
Design requirements
Successful overmoulding depends on material compatibility, bonding, part geometry, tool design and process control. The first material must be able to withstand the second moulding stage, and the design must support mechanical or chemical bonding where required.
Overmoulding, insert moulding and outsert moulding
These related processes all combine materials or components in a moulded part. Rutland Plastics has experience with insert and outsert moulding and can review whether overmoulding or another approach is better for the application.
Why early advice matters
Overmoulded parts should be designed for the process from the start. Material choice, draft, shut-off areas, tooling access and bonding surfaces all affect the outcome.
Add function, grip or protection to a plastic part
Rutland Plastics can review whether overmoulding, insert moulding or another manufacturing route is suitable for your component.
FAQs – Overmoulding in Injection Moulding
Overmoulding is moulding one material over another material or component.
It can add grip, sealing, cushioning, insulation, protection or appearance benefits.
They are related but not identical. Insert moulding places an insert into the tool before moulding around it.
No. Material compatibility and design need to be assessed.
Yes. The team can review whether overmoulding, insert moulding or another route is suitable.
