# 2040 T-slot extrusion, 2 × 4 in (10-series inch)

> What are the exact dimensions of 2040 T-slot extrusion (2 × 4 in)?

- Category: Hardware › Framing
- Kind: Hardware
- Basis: 80/20 Inc. 10 series (1 in), from 80/20's page for this profile (size, slot count, series, area, weight) and the 1010 and 1020 drawings of the same series for the slot (the page shows no drawing); every slot, lip, cavity, bore and outline number is the drawing's
- Page: https://xemstudio.com/objects/2040-t-slot-extrusion-inch/ · JSON: https://xemstudio.com/api/geometry?object=2040-t-slot-extrusion-inch · Plain text: https://xemstudio.com/objects/2040-t-slot-extrusion-inch/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

## Overall (mm)

| width | height |
|---|---|
| 101.6 | 50.8 |

**Exact dimensions.** Every file is drawn at true size with no printing tolerance. The holes and pins that meet another part are listed below under Mating features, with the fit each joint needs; open those by your printer's or process's clearance before making the part.

## Notes

- 2040 T-slot extrusion, 2 × 4 in (10-series inch): 2 × 4 in, 12 slots on a 1.000 in = 25.400 mm pitch (80/20 Inc. 10 series (1 in)). Source: 80/20's page for this profile (size, slot count, series, area, weight) and the 1010 and 1020 drawings of the same series for the slot (the page shows no drawing). Files: STEP and STL at 100, 1000 mm with square ends, and a DXF of the exact cross-section (mm), the master to extrude to any length. The section is centred on the origin and extruded along +Z from z = 0.
- Slot: opening 0.256 in = 6.502 mm, lip 0.087 in = 2.210 mm thick at the opening under a 2° drop-lock slope (0.093 in = 2.355 mm at the cavity wall), cavity 0.584 in = 14.834 mm wide under the lips, 0.323 in = 8.204 mm from the face to the cavity floor. Centre bore Ø0.205 in = 5.207 mm per cell (the largest thread whose tap drill fits inside: 1/4-20, 5.1 mm).
- Cavity side walls: the cavity is 0.584 in = 14.834 mm wide under the lips, then follows the diagonal webs (0.087 in = 2.210 mm thick, stated) down to the floor; the webs lie on the cell diagonals (45°), as drawn. The web thickness is the one stated on the same-series drawings named above.
- The closed hollows between cells are not fully dimensioned on the drawing, so they are drawn filled: the outline, slots and bores are exact, the bar is heavier than the real one.
- The drawing does not dimension the outer corner radii, so the corners are square: a pocket cut from this file clears the real rounded corners. The small alignment grooves on the faces are not dimensioned and are left off (the faces are flat).
- Wrapping it: to make a part that fits around the bar, subtract the 1000 mm file (or extrude the DXF) from your solid; the outline is the drawing's 2 × 4 in with no allowance, so open the pocket by your process's socket fit (see Mating features).
- Attachments: the 1 in 10-series T-nuts, end caps, feet, brackets, gussets, plates and slot covers are cut from these same numbers; the fit check (tools/asm_extrusion_fit.py) placed each one on this profile with zero overlap.

## Mating features (exact size; open press / slide / run / socket by your process clearance, leave designed and clamp as drawn)

| feature | exact | mates with | fit | files |
|---|---|---|---|---|
| slot opening | 0.256 in (6.50) | T-nut tongue, slot-cover stem (1 in 10-series) | slide | all |
| slot cavity | 0.584 in (14.83) wide under the lips, face to floor 0.323 in (8.20), lip 0.087 in (2.21) | T-nut body (slide-in, drop-in) | slide | all |
| centre bore | Ø0.205 in (5.21) | 1/4-20 thread (tap drill 5.1); end-cap pin | designed | all |
| outline | 2 × 4 in, square corners | end-cap outline, foot socket, a pocket that wraps the bar | socket | all |

## Sizes

| feature | size | from |
|---|---|---|
| outline | 2 × 4 in | drawing |
| slot pitch | 1.000 in = 25.400 mm | drawing |
| slot opening | 0.256 in = 6.502 mm | drawing |
| lip thickness at the opening | 0.087 in = 2.210 mm | drawing |
| lip underside slope (drop lock) | 2° | maker's page |
| cavity width under the lips | 0.584 in = 14.834 mm | drawing |
| face to cavity floor | 0.323 in = 8.204 mm | drawing |
| cavity depth under the lip (at the cavity wall) | 0.230 in = 5.849 mm | drawing |
| core between opposite floors | 0.354 in = 8.992 mm | pitch − 2 × face-to-floor (the drawing's own core figure is 0.356 in) |
| diagonal web | 0.087 in = 2.210 mm | drawing |
| centre bore | Ø0.205 in = 5.207 mm × 8 | drawing |
| cross-section area | 2.29 in² (1477 mm²) | maker's page |
| weight | 0.2233 lb/in (2.68 lb/ft; 3.99 kg/m) | maker's page (ft and kg/m converted) |
| Ix / Iy | 3.5168 / 1.0513 in⁴ | maker's page |
| area of this model's section | 4000.0 mm² (6.200 in²) | computed from the DXF |

## Where the files are

- 80/20 Inc.: [2040: 2.00 x 4.00 T-slotted profile, twelve open T-slots: product page with the cross-section drawing and section properties](https://8020.net/2040.html) — web — 80/20 site terms (verify at link)
- 80/20 Inc.: [1010 dimensioned cross-section drawing (same series slot)](https://8020.net/media/catalog/product/1/0/1010_dimensional_4.jpg) — image — 80/20 site terms (verify at link)
- 80/20 Inc.: [1020 dimensioned cross-section drawing (same series slot)](https://8020.net/media/catalog/product/1/0/1020_dimensional.png) — image — 80/20 site terms (verify at link)

## Free STEP/STL (2 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/2040-t-slot-extrusion-inch/index.json

- 2040in-100: [STEP](https://xemstudio.com/files/hardware/2040-t-slot-extrusion-inch/2040in-100.step) · [STL](https://xemstudio.com/files/hardware/2040-t-slot-extrusion-inch/2040in-100.stl) · [DXF](https://xemstudio.com/files/hardware/2040-t-slot-extrusion-inch/2040in-section.dxf) — 2040 T-slot extrusion, 2 × 4 in (10-series inch): 2 × 4 in section, 100 mm long, square ends; DXF = the exact cross-section in mm
- 2040in-1000: [STEP](https://xemstudio.com/files/hardware/2040-t-slot-extrusion-inch/2040in-1000.step) · [STL](https://xemstudio.com/files/hardware/2040-t-slot-extrusion-inch/2040in-1000.stl) · [DXF](https://xemstudio.com/files/hardware/2040-t-slot-extrusion-inch/2040in-section.dxf) — 2040 T-slot extrusion, 2 × 4 in (10-series inch): 2 × 4 in section, 1000 mm long, square ends; DXF = the exact cross-section in mm

## How it fits

### Parts that fit it
- [Slide-in T-nuts for 20, 30, 40, 45 mm and 1 in, 1.5 in T-slot extrusion](https://xemstudio.com/objects/slide-in-t-nuts/): tongue in the opening, body in the cavity (slide)
- [Drop-in T-nuts for 20, 30, 40, 45 mm and 1 in, 1.5 in T-slot extrusion](https://xemstudio.com/objects/drop-in-t-nuts/): drops through the opening, turns 90° in the cavity
- [L corner brackets for 20, 30, 40, 45 mm and 1 in, 1.5 in T-slot extrusion](https://xemstudio.com/objects/t-slot-corner-brackets/): legs flat on two profile faces at 90°
- [Inside corner gussets for 20, 30, 40, 45 mm and 1 in, 1.5 in T-slot extrusion](https://xemstudio.com/objects/t-slot-gussets/): legs on two profile faces in the inside corner
- [Snap-in slot covers for 20, 30, 40, 45 mm and 1 in, 1.5 in T-slot extrusion (100 mm)](https://xemstudio.com/objects/t-slot-covers/): stem in the slot opening, barb behind the lips
- [Joining plates, 2 × 3 holes, for 20, 30, 40, 45 mm and 1 in, 1.5 in T-slot extrusion](https://xemstudio.com/objects/t-slot-joining-plates/): holes over the slot centrelines on the profile pitch
- [End caps for every T-slot profile here (20, 30, 40, 45 mm and 1 in, 1.5 in series)](https://xemstudio.com/objects/t-slot-end-caps/): end-cap-10in-4x2: pins in the centre bores (press)

### Alternatives
- [1010 T-slot extrusion, 1 × 1 in (10-series inch)](https://xemstudio.com/objects/1010-t-slot-extrusion-inch/): same 1 in 10-series slot, 1 × 1 in
- [1020 T-slot extrusion, 1 × 2 in (10-series inch)](https://xemstudio.com/objects/1020-t-slot-extrusion-inch/): same 1 in 10-series slot, 1 × 2 in
- [1030 T-slot extrusion, 1 × 3 in (10-series inch)](https://xemstudio.com/objects/1030-t-slot-extrusion-inch/): same 1 in 10-series slot, 1 × 3 in

## Questions

**What is the slot size of 2040 extrusion?**

Opening 0.256 in = 6.502 mm, lip 0.087 in = 2.210 mm, cavity 0.584 in = 14.834 mm wide under the lips and 0.323 in = 8.204 mm deep from the face to the floor, per 80/20 Inc. 10 series (1 in)'s drawing.

**What T-nuts fit 2040 extrusion?**

The 1 in 10-series nuts: slide-in (tnut-slide-10in-1-4-20, tnut-slide-10in-10-32) and drop-in versions, threaded 1/4-20, 10-32 as tap-drill holes, cut to this slot's exact space.

**Can I subtract this file to make a part that fits the extrusion exactly?**

Yes: the outline is exactly 2 × 4 in with square corners (the real bar's corners are rounded, so the pocket clears them); extrude the DXF or subtract the 1000 mm STEP, then open the pocket by your fit.

**How heavy is 2040 extrusion?**

0.2233 lb/in (2.68 lb/ft), 2.29 in² section, as 80/20 states. This model's section is larger because closed hollows / cavity details the drawing leaves undimensioned are drawn filled; use the stated weight, not the model's volume.

**What in this model is not taken straight from the drawing?**

The closed hollows between cells are not fully dimensioned on the drawing, so they are drawn filled: the outline, slots and bores are exact, the bar is heavier than the real one. The drawing does not dimension the outer corner radii, so the corners are square: a pocket cut from this file clears the real rounded corners. Face grooves are left off.

## Fits with

- [1010 T-slot extrusion, 1 × 1 in (10-series inch)](https://xemstudio.com/objects/1010-t-slot-extrusion-inch/)
- [1020 T-slot extrusion, 1 × 2 in (10-series inch)](https://xemstudio.com/objects/1020-t-slot-extrusion-inch/)
- [1030 T-slot extrusion, 1 × 3 in (10-series inch)](https://xemstudio.com/objects/1030-t-slot-extrusion-inch/)
- [2020 T-slot extrusion, 2 × 2 in (10-series inch)](https://xemstudio.com/objects/2020-t-slot-extrusion-inch/)
- [Slide-in T-nuts for 20, 30, 40, 45 mm and 1 in, 1.5 in T-slot extrusion](https://xemstudio.com/objects/slide-in-t-nuts/)
- [Drop-in T-nuts for 20, 30, 40, 45 mm and 1 in, 1.5 in T-slot extrusion](https://xemstudio.com/objects/drop-in-t-nuts/)
- [End caps for every T-slot profile here (20, 30, 40, 45 mm and 1 in, 1.5 in series)](https://xemstudio.com/objects/t-slot-end-caps/)
- [L corner brackets for 20, 30, 40, 45 mm and 1 in, 1.5 in T-slot extrusion](https://xemstudio.com/objects/t-slot-corner-brackets/)