# Aluminium T-slot extrusion: 2020, 2040, 2060, 2080, V-slot, 3030, 3060, 4040, 4080, 1010, 1515

> What are the slot dimensions of 2020, 3030 and 4040 aluminium extrusion?

- Category: Hardware › Framing
- Kind: Hardware
- Basis: Common European / Misumi 20-, 30- and 40-series profiles (6 and 8 mm slots), OpenBuilds V-slot, and 80/20 10- and 15-series inch profiles; cavity dimensions typical of the 'standard' (non-light) profile, ±0.3 mm by maker
- Page: https://xemstudio.com/objects/t-slot-extrusions/ · JSON: https://xemstudio.com/api/geometry?object=t-slot-extrusions · Plain text: https://xemstudio.com/objects/t-slot-extrusions/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses

## Notes

- 20-series (2020, 2040…): 20 mm pitch, 6.0 mm slot opening, ~11 mm wide slot cavity behind 1.8 mm lips, 6 mm deep, Ø4.2 centre bore (tap M5). V-slot is the same with 6.2 mm opening and 45° chamfered lips for Delrin wheels. 30-series: 8 mm slot, Ø6.8 bore (M8). 40-series: 8 mm slot (10 mm on heavy), Ø6.8–8.5 bore. 80/20 10-series: 1 in, 0.256 in (6.5 mm) slot, 0.2 in bore (1/4-20); 15-series: 1.5 in, 0.32 in (8.2 mm) slot, 0.26 in bore (5/16-18).
- Print the profile to check brackets before cutting aluminium: 100 mm stubs here. Printed extrusion is not structural, but a printed 2020 stub with slide-in nuts is exactly how to prototype a mount.
- Design rule for attachments: anything that touches the extrusion face is flat; anything in the slot is 5.8 mm wide (6 mm slot) or 7.8 mm (8 mm slot) and no deeper than the lip + 0.5 mm unless it is a nut. Tongues on brackets stop rotation. M5 button heads on 20-series, M8 on 40-series.
- LES: the engine test stands and the generator rigs are 2020 and 2040 frames with the printed brackets in the companion entry.

## Sizes

| profile | size_mm | slot_mm | cavity_mm | depth_mm | bore_mm | type |
|---|---|---|---|---|---|---|
| 2020 | 20 × 20 | 6.0 | 11.0 | 6.0 | 4.2 | T |
| 2040 | 40 × 20 | 6.0 | 11.0 | 6.0 | 4.2 | T |
| 2060 | 60 × 20 | 6.0 | 11.0 | 6.0 | 4.2 | T |
| 2080 | 80 × 20 | 6.0 | 11.0 | 6.0 | 4.2 | T |
| 4040 (20-series double) | 40 × 40 | 6.0 | 11.0 | 6.0 | 4.2 | T |
| V-slot 2020 | 20 × 20 | 6.2 | 11.0 | 6.0 | 4.2 | V |
| V-slot 2040 | 40 × 20 | 6.2 | 11.0 | 6.0 | 4.2 | V |
| V-slot 2080 | 80 × 20 | 6.2 | 11.0 | 6.0 | 4.2 | V |
| 3030 | 30 × 30 | 8.0 | 16.5 | 8.5 | 6.8 | T |
| 3060 | 60 × 30 | 8.0 | 16.5 | 8.5 | 6.8 | T |
| 4040 | 40 × 40 | 8.0 | 20.0 | 9.5 | 6.8 | T |
| 4080 | 80 × 40 | 8.0 | 20.0 | 9.5 | 6.8 | T |
| 4040 heavy (10 mm slot) | 40 × 40 | 10.0 | 22.0 | 11.0 | 8.5 | T |
| 1010 (1 in, 10-series) | 25.4 × 25.4 | 6.5 | 14.4 | 7.1 | 5.1 | T |
| 1020 | 50.8 × 25.4 | 6.5 | 14.4 | 7.1 | 5.1 | T |
| 1515 (1.5 in, 15-series) | 38.1 × 38.1 | 8.2 | 20.5 | 9.6 | 6.6 | T |

## Where the files are

- Wikipedia: [T-slot structural framing](https://en.wikipedia.org/wiki/T-slot_structural_framing) — web — CC BY-SA 4.0 (text)
- Misumi: [Aluminum extrusions HFS5 (20 mm) / HFS6 (30 mm) / HFS8 (40 mm) series drawings](https://us.misumi-ec.com/vona2/mech/M1500000000/M1501000000/) — web, STEP, PDF — Misumi site terms (verify at link)
- 80/20 Inc.: [10-series and 15-series T-slot profiles](https://8020.net/) — web, STEP, PDF — 80/20 site terms (verify at link)
- OpenBuilds: [V-Slot linear rail profiles](https://openbuildspartstore.com/v-slot-linear-rail/) — web, STEP — OpenBuilds, CC BY-SA 4.0 (V-Slot) (verify at link)
- Long Earth Society: [Engine and rig builds on extrusion frames](https://longearthsociety.com/engineering/) — web, video — LES site

## Free STEP/STL (16 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/t-slot-extrusions/index.json

- 2020-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/2020-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/2020-100.stl) — 2020: 20 × 20 mm, slot 6.0 mm, 100 mm stub
- 2040-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/2040-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/2040-100.stl) — 2040: 40 × 20 mm, slot 6.0 mm, 100 mm stub
- 2060-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/2060-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/2060-100.stl) — 2060: 60 × 20 mm, slot 6.0 mm, 100 mm stub
- 2080-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/2080-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/2080-100.stl) — 2080: 80 × 20 mm, slot 6.0 mm, 100 mm stub
- 2020-2x2-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/2020-2x2-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/2020-2x2-100.stl) — 4040 (20-series double): 40 × 40 mm, slot 6.0 mm, 100 mm stub
- vslot-2020-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/vslot-2020-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/vslot-2020-100.stl) — V-slot 2020: 20 × 20 mm, slot 6.2 mm, 100 mm stub
- vslot-2040-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/vslot-2040-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/vslot-2040-100.stl) — V-slot 2040: 40 × 20 mm, slot 6.2 mm, 100 mm stub
- vslot-2080-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/vslot-2080-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/vslot-2080-100.stl) — V-slot 2080: 80 × 20 mm, slot 6.2 mm, 100 mm stub
- 3030-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/3030-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/3030-100.stl) — 3030: 30 × 30 mm, slot 8.0 mm, 100 mm stub
- 3060-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/3060-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/3060-100.stl) — 3060: 60 × 30 mm, slot 8.0 mm, 100 mm stub
- 4040-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/4040-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/4040-100.stl) — 4040: 40 × 40 mm, slot 8.0 mm, 100 mm stub
- 4080-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/4080-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/4080-100.stl) — 4080: 80 × 40 mm, slot 8.0 mm, 100 mm stub
- 4040-heavy-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/4040-heavy-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/4040-heavy-100.stl) — 4040 heavy (10 mm slot): 40 × 40 mm, slot 10.0 mm, 100 mm stub
- 1010-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/1010-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/1010-100.stl) — 1010 (1 in, 10-series): 25.4 × 25.4 mm, slot 6.5 mm, 100 mm stub
- 1020-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/1020-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/1020-100.stl) — 1020: 50.8 × 25.4 mm, slot 6.5 mm, 100 mm stub
- 1515-100: [STEP](https://xemstudio.com/files/hardware/t-slot-extrusions/1515-100.step) · [STL](https://xemstudio.com/files/hardware/t-slot-extrusions/1515-100.stl) — 1515 (1.5 in, 15-series): 38.1 × 38.1 mm, slot 8.2 mm, 100 mm stub

## Questions

**What is the slot width on 2020 extrusion?**

6.0 mm opening (6.2 on V-slot) with a cavity about 11 mm wide and 6 mm deep behind 1.8 mm lips; the centre bore is Ø4.2 for an M5 tap.

**What is the difference between 2020 and V-slot 2020?**

Same 20 × 20 size and 6 mm-class slot; V-slot adds 45° chamfers on the slot lips so Delrin V-wheels ride in the groove. T-nuts fit both.

**What size T-nut for 4040 extrusion?**

8 mm slot: M6 or M8 T-nuts (M5 on the 20-series 6 mm slot; 1/4-20 on 80/20 10-series).

**Is 2020 extrusion metric or inch?**

Metric (20 mm). The inch equivalents are 80/20 10-series (1 in, 25.4 mm) and 15-series (1.5 in); their slots and bores differ, so brackets don't interchange.

## Fits with

- [T-slot attachments: slide-in and drop-in T-nuts, corner brackets, gussets, end caps, slot covers, feet, hole plates](https://xemstudio.com/objects/t-slot-brackets-and-nuts/)
- [2020 aluminum extrusion](https://xemstudio.com/objects/2020-extrusion/)
- [Button head socket screws, M2–M8 (ISO 7380)](https://xemstudio.com/objects/button-head-screws-metric/)
- [Hex nuts, M2–M8 (ISO 4032)](https://xemstudio.com/objects/hex-nuts-metric/)
- [MGN9 / MGN12 / MGN15 miniature linear rails and carriages](https://xemstudio.com/objects/mgn-linear-rails/)
- [NEMA 17 stepper motor](https://xemstudio.com/objects/nema-17-stepper/)