# N20 micro gearmotor 12 × 10 mm, Ø3 D-shaft

> What is the N20 motor size and shaft diameter?

- Category: Hardware › Motion
- Kind: Hardware
- Basis: Common supplier drawings for the N20 micro metal gearmotor; gearbox length varies by ratio
- Page: https://xemstudio.com/objects/n20-gearmotor/ · JSON: https://xemstudio.com/api/geometry?object=n20-gearmotor · Plain text: https://xemstudio.com/objects/n20-gearmotor/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

- The N20 is 12 × 10 mm in section: a 15 mm motor with R2 rounded edges plus a gearbox 9–12 mm long depending on ratio; the file has the 9 mm gearbox (24 mm body).
- The output is a Ø3 D-shaft, 2.5 mm across the flat, 10 mm long; 34 mm overall.
- The gearbox face has two M1.6 holes 9 mm apart, drawn as Ø1.6 × 4 deep.

## 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 |
|---|---|---|---|---|
| N20 shaft | Ø3 D (2.5 across the flat) | wheel hub | press | motor-n20-* |

## Sizes

| feature | size_mm |
|---|---|
| section | 12 × 10 |
| motor | 15 |
| gearbox (this file) | 9 |
| shaft | Ø3 D, 2.5 across flat × 10 |
| face holes | 2 × M1.6 on 9 |

## Where the files are

- Pololu: [Micro metal gearmotor dimension diagram](https://www.pololu.com/category/60/micro-metal-gearmotors) — PDF, STEP — Pololu site terms (verify at link)
- DFRobot: [TT geared motor drawing](https://www.dfrobot.com/product-100.html) — web — DFRobot site terms (verify at link)
- Wikipedia: [DC motor](https://en.wikipedia.org/wiki/DC_motor) — web — CC BY-SA 4.0 (text)

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

Index: https://xemstudio.com/files/hardware/n20-gearmotor/index.json

- motor-n20-9mm-gearbox: [STEP](https://xemstudio.com/files/hardware/dc-motors-775-n20-tt/motor-n20-9mm-gearbox.step) · [STL](https://xemstudio.com/files/hardware/dc-motors-775-n20-tt/motor-n20-9mm-gearbox.stl) — N20 micro gearmotor: 12 × 10 × 15 motor + 9 mm gearbox, Ø3 D-shaft (2.5 across the flat) × 10

## How it fits

### Connects to
- [Flexible shaft couplers, 5–10 mm bores](https://xemstudio.com/objects/shaft-couplers/): Ø3 D-shaft into a wheel or coupler hub (press)

### Alternatives
- [TT yellow gearmotor 70 × 22.5 × 18.5 mm, Ø5.5 double-D shafts](https://xemstudio.com/objects/tt-gearmotor/): larger plastic-gearbox motor

## Questions

**What is the N20 motor shaft size?**

3 mm D-shaft, 2.5 mm across the flat, about 10 mm long.

**How long is an N20 gearmotor?**

15 mm motor plus a 9–12 mm gearbox; the file is 24 mm body, 34 mm with the shaft.

## Fits with

- [775 brushed DC motor Ø42 × 66.7 mm, Ø5 shaft](https://xemstudio.com/objects/775-dc-motor/)
- [TT yellow gearmotor 70 × 22.5 × 18.5 mm, Ø5.5 double-D shafts](https://xemstudio.com/objects/tt-gearmotor/)
- [Flexible shaft couplers, 5–10 mm bores](https://xemstudio.com/objects/shaft-couplers/)