Design Hints for Extrusion
Designing for extrusion is an important part of your project development. Although these are not hard and fast rules, these "design hints" can help you avoid common pitfalls and reduce cost drivers on an extruded part.
WALL THICKNESS: The heavier the wall, the more material required, and the slower the production. Rule of thumb: the ideal wall is 0.7mm-1.5mm. Maintain as even a wall as possible, because abrupt wall thickness changes make for more expensive tooling and slower production. Make unavoidable changes as gradual as possible. Details on the inside of tubes should be thinner than the tube walls. Rule of thumb: make detail thickness 70% of tube wall.
THROUGH HOLES: Avoid if possible. Generally, they are preferred to uneven walls. Tiny through holes are expensive to tool and produce.
RADII: Be as generous as possible. Sharp corners are difficult to extrude and provide stress risers.
TOLERANCES: The tighter they are, the more expensive the extrusion. Be realistic. Indicate the truly important dimensions. Show how the part will be used.
MATERIALS: Some materials are easier to extrude than others. Some are more forgiving when design rules are broken. Some will accept a heavier loading of a reinforcement or filler than others. Materials selection is the single most important factor in design success, precision production and scrap rate. Contact us for our recommendation.