How to Design for Extrusion: Tips for Engineers

Designing a part for plastic extrusion is about more than the shape — it’s about making sure the profile can be manufactured efficiently, perform reliably, and meet your end-use requirements.

At Lincoln Plastics, we work with engineers every day to bring their ideas from concept to production. Whether you’ve designed extruded parts before or are new to the process, here are a few key tips to design smarter for extrusion.

1️⃣ Keep Wall Thickness Consistent

Uniform wall thickness helps maintain smooth material flow through the die and consistent cooling during production. Large variations in wall thickness can lead to warping, uneven strength, or cosmetic issues.
When thickness changes are necessary, taper transitions gradually to reduce stress points.

2️⃣ Understand Material Behavior

Not all plastics behave the same. Some materials shrink more during cooling, while others expand or require tighter dimensional control.
Choosing the right resin early — and knowing how it behaves in extrusion — can help you set realistic tolerances and avoid costly tooling changes later.

3️⃣ Include Functional Design Features Carefully

Ribs, grooves, or snap fits can often be integrated into extruded profiles, but placement matters. Sharp corners or deep recesses may cause uneven flow or stress concentrations.
Our engineering team can help refine these features to make them easier to extrude and more durable in use.

4️⃣ Consider the Cooling and Pulling Process

After exiting the die, the extrusion is cooled and pulled to maintain shape and dimensional accuracy. Designs with wide, flat areas or thick cross-sections may require special cooling attention.
Working with your extrusion partner early allows these factors to be accounted for before tooling begins.

5️⃣ Engage Early and Communicate Often

The most successful projects start with collaboration. Involving your extrusion partner during the design phase allows for material recommendations, cost-saving insights, and better manufacturability.
At Lincoln Plastics, we pride ourselves on partnering closely with OEM engineers to optimize every design before it hits production.

Turning Design into Production

A well-designed extrusion is the result of good engineering and open communication. When design intent and process capability align, you get a part that performs — and a production process that runs efficiently.

Contact us today to collaborate on your next extrusion design.

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