Designing Thin-Wall Aluminium Profiles: Wall Thickness Limits

How thin can an aluminium enclosure wall go? Wall-thickness rules, stability limits and machining-rigidity tips for extruded profiles.

A thin wall is the fastest way to cut weight and material cost on an extruded enclosure — but only if the section stays stable on the press and rigid enough to machine. This is how we set the limit.

The headline number — and what it hides

We run 0.3 mm walls in stable volume production. That number is a result, not a target: the real limit depends on how wide the flat is, whether the section is hollow, and how the part is held during CNC machining. A narrow, supported wall can go thinner than a wide, open one.

Three rules we apply before cutting the die

• Keep thin walls short and supported — long, open flats bow on the press.
• Leave metal behind a thin wall where a hole or thread will be machined.
• Avoid sudden thickness steps; ramp them so the extrusion fills cleanly.

Machining rigidity is the hidden constraint

A wall can extrude fine yet deflect under a milling cutter, spoiling flatness or hole position. When we review your drawing we mark which walls can stay thin and where they need backing — often by integrating a rib rather than thickening the whole wall. That keeps weight down while holding ±0.05 mm on machined features.

Send the cross-section and we will tell you where the wall can go thin and where it still needs metal behind it. Open a DFM review.