Design for Manufacturability: Tips for Streamlining Extrusion Projects Early

When it comes to custom plastic extrusion projects, early-stage design decisions significantly impact the overall success, cost, and timeline of manufacturing. Design for Manufacturability (DFM) is a strategic approach that focuses on simplifying product design to make production as efficient and cost-effective as possible, without sacrificing quality or functionality. 

For extrusion projects, applying DFM principles early can streamline tooling, reduce material waste, and minimize post-processing steps. Below are key tips to keep in mind during the design phase to optimize manufacturability in extrusion projects.

Keep Wall Thickness Consistent

One of the most critical aspects of extrusion design is maintaining uniform wall thickness. Variations can cause uneven cooling, warping, or weak points that compromise part strength and appearance. Thin sections may cool too quickly and shrink excessively, while thick sections can cool too slowly, creating internal stresses or sink marks.

A consistent wall thickness promotes smooth material flow through the die and uniform cooling, which leads to higher-quality extrusions and fewer defects. If thickness changes are necessary for function, transitions should be gradual with smooth radii.

Simplify Profile Geometry

While extrusion can accommodate complex shapes, overly intricate profiles can increase tooling complexity and cost. Sharp internal corners, tiny slots, or thin fins may cause material flow problems or die wear. Whenever possible, use rounded corners, avoid unnecessary detail, and minimize sharp changes in direction.

Simpler geometries not only reduce the risk of defects but also improve production speed and tool longevity.

Design for Material Flow

Extrusion relies on pushing molten plastic through a die to form a consistent cross-section. Features that disrupt material flow—such as abrupt thickness changes or isolated “islands” of plastic within the profile—can create voids or weak spots.

Designing with smooth transitions and continuous sections ensures better flow, reducing the risk of air entrapment or inconsistent extrusion pressure. For profiles with hollow sections, internal supports or webs can improve stability without compromising material flow.

Consider Post-Processing Needs

Extruded parts often require secondary operations like cutting, punching, drilling, or surface finishing. Designing features that facilitate these processes early—such as knockouts, pilot holes, or snap-fit connectors—can save time and costs later.

Clearances and tolerances should also be specified to accommodate assembly requirements without causing interference or excessive rework.

Choose the Right Material Early

Material selection influences not only the part’s properties but also extrusion ease. Some materials flow better, cool faster, or resist wear differently. Selecting a suitable resin that aligns with your product’s functional and environmental needs—and is compatible with extrusion—can avoid headaches during production.

Collaborating with your extrusion partner early on material choice helps ensure the selected plastic supports your design goals and manufacturing constraints.

Prototype and Test Early

Early prototyping allows you to identify manufacturability issues before investing in expensive tooling. Even simple 3D printed models can reveal fit and function problems. Once you have a prototype die, test runs help optimize tool design and process parameters.

Iterative testing and feedback loops shorten development time and reduce costly revisions during production.

Custom Extrusion with Inplex

Looking for quality custom extrusion products and services? Inplex is one of the leading custom extrusion services in the US and has almost 60 years of experience. We pride ourselves on our ability to put the right talent and technology in place to perform the best possible job for our clients.

We own a 42,000 sq. ft. facility in Naperville, Illinois, that is temperature-controlled and features an environmentally friendly closed-loop water cooling system. If you have specific needs or questions, don’t hesitate to contact us!