4040 Aluminum Extrusion
4040 aluminum extrusion is a 40 × 40 mm (1.57 × 1.57 in) T-slot profile with a slot on each face. It is the heavier of the two sizes we design furniture with, a good fit for desks, workbenches and tall shelving where the frame carries real weight. Every Slot & Shaft 4040 design comes with a parts list generated from the same 3D model you see, so the slot width, nuts and bolts on the list all match.
4040 specs at a glance
Slot & Shaft 4040 designs use the European-style “8 series” profile with a 10 mm slot. Every value in this table is MISUMI’s published figure for its HFS8-4040 profile, not our own measurement.
| Spec | Value | Source |
|---|---|---|
| Cross-section | 40 × 40 mm (1.57 × 1.57 in), 4 slotted faces | MISUMI HFS8-4040 |
| Slot width | 10 mm ±0.36 mm (0.39 in) | MISUMI HFS8-4040 |
| Bolt size | M8 | MISUMI HFS8-4040 |
| Weight per meter | 1.73 kg/m (1.16 lb/ft) | MISUMI HFS8-4040 |
| Cross-sectional area | 640 mm² (0.99 in²) | MISUMI HFS8-4040 |
| Moment of inertia (Ix = Iy) | 10.4 × 10⁴ mm⁴ (0.25 in⁴) | MISUMI HFS8-4040 |
| Material | A6005C-T5 aluminum alloy, anodized | MISUMI HFS8-4040 |
| Center bore | Ø10.5 mm (0.41 in) | MISUMI HFS8 catalog page |
| Cut-to-order length | 50–4,000 mm (2–157 in), in 0.5 mm steps, tolerance ±0.5 mm | MISUMI HFS8-4040 |
| Compatible nuts | Slot-10 T-nuts and spring nuts, M3–M8 (e.g. MISUMI HNTP8) | MISUMI HNTP8 / SHNTP8 |
Not every “4040” is the same profile. Some sellers list 4040 profiles with an 8 mm slot and different weights (example: one manufacturer lists 1.45, 1.85 and 2.2 kg/m variants with an 8 mm slot). Nuts made for a 10 mm slot will not seat in an 8 mm slot. Check the slot width before you buy. Our parts lists name it on every line.
Need a cross-section drawing or CAD file? Download it from MISUMI’s product page: HFS8-4040 CAD download. We don’t host CAD files ourselves.
Fittings that work with 4040
Every 4040 design uses 10 mm slot (M8) hardware. Start here:
- T-slot nuts & bolts: spring nuts you can drop in after the frame is built, plus M8 bolts.
- L brackets: the simplest way to join two 4040 pieces at 90°.
- Connectors: hidden joints, corner cubes and inline joiners.
Projects built with 4040
Open any project, set your own width, depth and height, and the parts list updates with the model. Each line links to a US seller. Prefer one box with everything pre-cut? Buy as a pre-cut kit — join the waitlist.
How to choose between 4040 and 3030
| 3030 | 4040 | |
|---|---|---|
| Cross-section | 30 × 30 mm | 40 × 40 mm |
| Slot / bolt | 8 mm / M6 | 10 mm / M8 |
| Weight per meter (reference profile) | 0.9 kg/m | 1.73 kg/m |
| Moment of inertia (reference profile) | 2.83 × 10⁴ mm⁴ | 10.4 × 10⁴ mm⁴ |
| Typical use in our designs | Shelves, carts, enclosures | Desks, workbenches, tall frames |
All figures in this comparison are MISUMI’s published values for HFS6-3030 and HFS8-4040. Moment of inertia measures how much a beam resists bending. The 4040 profile’s moment of inertia (10.4 × 10⁴ mm⁴) is roughly 3.7× that of the 3030 profile (2.83 × 10⁴ mm⁴), so a 4040 beam of the same length sags noticeably less under the same load.
FAQ
What does “4040” mean?
It is the cross-section in millimeters: 40 mm × 40 mm. Inch-based profiles use different names, and their slots and hardware don’t interchange with metric 4040.
What size bolts fit 4040 aluminum extrusion?
The 10 mm slot version we use takes M8 bolts, with nuts from M3 to M8 for lighter attachments (MISUMI). Some 4040 profiles on the market have an 8 mm slot instead. Check before you buy.
How much does 4040 aluminum extrusion weigh?
The reference profile weighs 1.73 kg per meter (about 1.16 lb per foot) (MISUMI HFS8-4040). Other brands’ 4040 profiles can be lighter or heavier depending on wall design.
How much weight can a 4040 frame hold?
It depends on span, joints and how the load is applied, so we don’t publish load numbers for our designs.
Can I buy 4040 cut to length from you?
Not yet. Right now every parts list links to US sellers who cut to length. If you’d rather get a single pre-cut kit from us, join the waitlist on any project page.
Is 4040 overkill for a desk?
It depends on the size of the desk. 4040 is the stiffer profile: its moment of inertia is 10.4 × 10⁴ mm⁴ versus 2.83 × 10⁴ mm⁴ for 3030 (MISUMI HFS8-4040, HFS6-3030). That matters most for wide desks and tall legs. 3030 weighs about half as much per meter (0.9 vs 1.73 kg/m). Open the desk template and switch the profile to compare; the parts list updates as you go.