Good design for aluminum extrusion starts with understanding both the constraints and the opportunities of the process. By following these guidelines, you can reduce tooling costs, improve part quality, and accelerate time to production. Whether you are designing your first extrusion profile or optimizing an existing one, these principles will help you get the most from the aluminum extrusion process.
Extrusion Design Guidelines
Optimize your aluminum extrusion profile design for manufacturability, performance, and cost-efficiency with our comprehensive engineering guidelines.
Section 01
Wall Thickness
Wall thickness is one of the most critical factors in extrusion profile design. It affects material cost, structural performance, die life, and surface quality.
- Minimum wall thickness: 1.0mm for 6063 alloy, 1.2mm for 6061 alloy
- Recommended practice: Maintain uniform wall thickness throughout the profile wherever possible
- Transitions: Use gradual transitions between thick and thin sections with a maximum ratio of 3:1
- Design tip: Thinner walls reduce material cost and weight but may affect structural performance — balance both requirements carefully
Section 02
Tolerances
Achievable dimensional tolerances depend on profile size, alloy, and complexity. The table below outlines our standard and precision tolerance capabilities.
| Dimension | Standard Tolerance | Precision Tolerance |
|---|---|---|
| Wall Thickness | ±0.15mm | ±0.10mm |
| Profile Width (up to 25mm) | ±0.15mm | ±0.10mm |
| Profile Width (25–50mm) | ±0.20mm | ±0.13mm |
| Profile Width (50–100mm) | ±0.30mm | ±0.20mm |
| Straightness | 0.5mm/300mm | 0.3mm/300mm |
| Twist | 1°/m | 0.5°/m |
| Angularity | ±1° | ±0.5° |
Section 03
Corner Radii
Properly designed corner radii are essential for achieving high-quality extrusions. Sharp corners create stress concentrations, increase die wear, and hinder metal flow during the extrusion process.
- Avoid sharp corners: They create stress concentrations and accelerate die wear
- Minimum internal radius: 0.5mm
- Recommended internal radius: Equal to the wall thickness of the profile
- External radius: Internal radius plus the wall thickness
- Benefits of proper radii: Better metal flow, longer die life, and stronger profiles with reduced risk of cracking
Section 04
Hollow Profiles
Hollow and semi-hollow profiles offer excellent strength-to-weight ratios but require careful design consideration due to their more complex tooling requirements.
- Semi-hollow vs fully hollow: Semi-hollow sections use a simpler die and cost less to produce than fully enclosed hollow sections
- Tongue ratio: For semi-hollow profiles, the depth-to-opening ratio should be less than 3:1
- Multi-hollow sections: Require bridge (porthole) dies, which have higher tooling costs but enable complex internal geometries
- Minimum opening: For hollow sections, the minimum internal opening is 3mm × 3mm
- Design tip: Consider semi-hollow alternatives to fully enclosed sections to reduce die cost and improve extrusion speed
Section 05
Design Tips for Manufacturability
Apply these proven design principles to optimize your extrusion profiles for production efficiency, assembly simplicity, and overall cost-effectiveness.
Symmetry
Design symmetrical profiles where possible for even metal flow during extrusion and reduced distortion during cooling and stretching.
Screw Bosses
Add screw channels directly into the extrusion profile to eliminate secondary drilling and machining operations, reducing cost and lead time.
Snap-Fit Features
Design interlocking profiles with snap-fit connections for tool-free assembly, simplifying installation and reducing labor costs on the production line.
Heat Sink Fins
Fin height-to-gap ratio should not exceed 8:1 for optimal extrusion. Taller, thinner fins require more extrusion pressure and risk die breakage.
Weight Reduction
Use hollow sections and ribbed designs instead of solid cross-sections to achieve equivalent structural performance at significantly lower weight and cost.
Surface Quality
Place parting lines and die marks on non-visible surfaces. Specify critical surface requirements early so die design can accommodate them.