Buying guide

How to Choose Aluminum Extrusion: 2020, 2040, 3030, 4040 and EU vs GB

What the profile numbers mean, how to pick a size for your frame, and what to tell a supplier when ordering cut-to-length profile.

T-slot aluminum extrusion is the standard frame material for 3D printers, CNC routers, laser engravers, workbenches and machine guards. Two things define a profile: its size and its standard.

What the numbers mean

The model number is the cross-section in millimetres. 2020 is 20 x 20 mm, 2040 is 20 x 40 mm, 3030 is 30 x 30 mm and 4040 is 40 x 40 mm. Wider profiles such as 2080 or 20100 have more slots along the long side.

As a rule, a larger cross-section bends less over the same span. For long spans or heavy loads, go up one size or use a double-width profile.

EU vs GB standard

Profiles of the same size are made to different standards. EU (European standard) profiles are the common choice for machines sold internationally. GB (Chinese national standard) profiles match many machines designed in China. The slot shape differs, so nuts, T-bolts and brackets must match the standard: an EU 2020 profile and a plain 2020 profile are not the same part. If your design does not say which standard it uses, measure the slot or send us a drawing before ordering.

Ordering cut-to-length profile

1. Standard (EU or GB) and model, for example EU 2040.
2. Color: silver or black.
3. Each length in mm and the quantity per length.
4. The connectors you plan to use, so we can check they fit the slot.

Shop: EU standard profile (cut to length) · GB standard profile (cut to length) · aluminum profile parts · read also T-nut types and lead screw vs belt drive