# LM8UU linear bearing Ø8 × Ø15 × 24

> What are the LM8UU bearing dimensions?

- Category: Hardware › Motion
- Kind: Hardware
- Basis: Industry-standard LM8UU: dr 8, D 15, L 24; retaining-ring grooves 1.1 wide to Ø14.3, outer faces 17.5 apart
- Page: https://xemstudio.com/objects/lm8uu-bearing/ · JSON: https://xemstudio.com/api/geometry?object=lm8uu-bearing · Plain text: https://xemstudio.com/objects/lm8uu-bearing/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses

**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

- Ø8 bore × Ø15 OD × 24 long.
- Two retaining-ring grooves 1.1 wide, down to Ø14.3, with their outer faces 17.5 apart (grooves from 3.25 to 4.35 and 19.65 to 20.75 along the length).
- Related sizes: LM8LUU 8 × 15 × 45; LM10UU 10 × 19 × 29; LM12UU 12 × 21 × 30.
- The OD sits in a Ø15 housing (the SC8UU block) and the bore slides on an Ø8 rod; fits are under Mating features.

## 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 |
|---|---|---|---|---|
| bearing OD | Ø15 × 24 | housing bore | press | lm8uu* |
| bore | Ø8 | 8 mm rod (slides on it) | designed | lm8uu* |

## Sizes

| feature | value_mm |
|---|---|
| bore | 8 |
| OD | 15 |
| length | 24 |
| grooves | 1.1 wide to Ø14.3, 17.5 apart (outer faces) |

## Where the files are

- McMaster-Carr: [Linear ball bearings (free STEP/IGES/STL per part, for your own design use; no redistribution)](https://www.mcmaster.com/products/linear-bearings/) — STEP, IGES, STL, PDF — McMaster-Carr site terms: personal design use, no redistribution (verify at link)
- Wikipedia: [Linear-motion bearing](https://en.wikipedia.org/wiki/Linear-motion_bearing) — web — CC BY-SA 4.0 (text)

## Free STEP/STL (1 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/lm8uu-bearing/index.json

- lm8uu: [STEP](https://xemstudio.com/files/hardware/lm8uu-linear-bearing/lm8uu.step) · [STL](https://xemstudio.com/files/hardware/lm8uu-linear-bearing/lm8uu.stl) — LM8UU: Ø8 bore × Ø15 × 24; ring grooves 1.1 wide to Ø14.3, 17.5 apart

## How it fits

### Goes in or on
- [Linear rod Ø8 × 300](https://xemstudio.com/objects/linear-rod-8mm/): Ø8 bore on the rod
- [SC8UU slide block for an LM8UU](https://xemstudio.com/objects/slide-block-sc8uu/): Ø15 OD in the block

### Alternatives
- [MGN9C/H, MGN12C/H and MGN15H carriages](https://xemstudio.com/objects/mgn-carriages/): rail carriage

## Questions

**What are LM8UU dimensions?**

8 mm bore, 15 mm OD, 24 mm long, two grooves 1.1 wide to Ø14.3, 17.5 mm apart over their outer faces.

**What housing bore does an LM8UU take?**

Ø15, the bearing OD; the SC8UU block file has it.

## Fits with

- [Linear rod Ø8 × 300](https://xemstudio.com/objects/linear-rod-8mm/)
- [SC8UU slide block for an LM8UU](https://xemstudio.com/objects/slide-block-sc8uu/)
- [SK8 rod support for Ø8 rods](https://xemstudio.com/objects/rod-support-sk8/)
- [MGN9C/H, MGN12C/H and MGN15H carriages](https://xemstudio.com/objects/mgn-carriages/)