Plastic Injection Moulding

Our plastic injection moulding process produces custom - rapid prototypes and end-use production parts in 15 days or less. We use aluminium moulds that offer cost-efficient tooling and accelerated manufacturing cycles, and stock more than 100 different thermoplastic resins.

Plastic Injection Moulding design guidelines will help you understand capabilities and limitations 

Why Choose Plastic Injection Moulding For Your Project?

Protolabs utilise a rapid injection moulding a technology-driven process that leverages manufacturing automation. CAD models are sent directly to the production floor where mould milling begins, but in most cases, moulds are fabricated from aluminium, not steel. This allows for faster and most cost-effective tooling when compared to traditional steel moulds.. We offer a number of additional moulding and tooling services to support your project.

How Does Plastic Injection Moulding Work?

The thermoplastic injection molding process at Protolabs is a standard process involving an aluminium mould with no heating or cooling lines running through it, which means cycle times are a bit longer. It allows our moulders to monitor fill pressure, cosmetic concerns, and the basic quality of the parts.

Resin pellets are loaded into a barrel where they will eventually be melted, compressed, and injected into the mould’s runner system. Hot resin is shot into the mould cavity through the gates and the part is moulded. Ejector pins facilitate removal of the part from the mould where it falls into a loading bin. When the run is complete, parts (or the initial sample run) are boxed and shipped shortly thereafter. Request your Free Design Cube which shows surface finishes and thick and thin finishes.

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  • 25 to 10,000+
  • Shipped in 15 days or less
Common Applications
  • low-volume production
  • bridge tooling
  • pilot runs
  • functional prototyping


Watch: Injection Moulding

Rapid injection moulding works best for on-demand production, bridge tooling, pilot runs, and functional prototyping. Our affordable aluminium moulds and quick turnaround times help reduce design risks and limit overall production costs.


Watch: ProtoQuote with Design Analysis (UK)

Product designers and engineers can upload a 3D CAD model online at any time to receive an interactive ProtoQuote® with free design for manufacturability (DFM) analysis and real-time pricing information within hours. The DFM analysis helps eliminate potential problems like sink, challenging undercuts or walls that are too thin or thick. Once a part design is ready and a quote approved, production begins almost immediately. Upload a part today for a ProtoQuote with design analysis.

Design Guidelines

Our basic guidelines for plastic injection moulding include important design considerations to help improve part mouldability, enhance cosmetic appearance, and reduce overall production time.


Press operator examines liquid silicone rubber part

Free mouldability analysis within hours