# Pololu 37D metal gearmotor (100:1, #4745): Ø36.8 body, 6 mm shaft and M3 face-mount holes

> What are the Pololu 37D metal gearmotor dimensions, shaft and mounting holes?

- Category: Electronic components › Motors
- Kind: Modern device
- Basis: Pololu product page #4745 and the Pololu 37D metal gearmotor dimension diagram.
- Page: https://xemstudio.com/objects/pololu-37d-metal-gearmotor/ · JSON: https://xemstudio.com/api/geometry?object=pololu-37d-metal-gearmotor · Plain text: https://xemstudio.com/objects/pololu-37d-metal-gearmotor/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

## Overall (mm)

| length | width | height |
|---|---|---|
| 79.0 | 36.8 | 36.8 |

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

## Notes

- Datum: motor axis on Z, centred on X and Y; back of the motor can on z=0, gearbox face plate at z=57.0.
- Body Ø36.8 × 57.0 (100:1, no encoder); central boss Ø12.0 × 6.0; output shaft Ø6.0 D-shaft × 16.0, ending at z=79.0.
- Six M3 tapped holes in the face plate, 3.0 mm max screw engagement, on a Ø31.0 bolt circle (hexagon, 15.5 between neighbours), first hole on +X.
- Gearbox length varies with ratio: 21.5 (19:1, 30:1), 24.0 (50:1, 70:1), 26.5 (100:1, 131:1, 150:1); encoder versions add a rear encoder.
- Modelled: body as one Ø36.8 cylinder, boss, shaft (flat not modelled), face holes. Not modelled: rear terminals.
- Exact nominal mm.

## 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 |
|---|---|---|---|---|
| Face-plate holes | 6 × M3 on Ø31.0, 3.0 deep max | M3 screws through an L-bracket | designed | all |
| Output shaft | Ø6.0 D-shaft, 16.0 long | 6 mm wheel hub or coupler | slide | all |
| Gearbox body | Ø36.8 | clamp-style motor mount | clamp | all |

## Sizes

| hole | x (mm) | y (mm) | thread |
|---|---|---|---|
| 1 | 15.5 | 0 | M3 |
| 2 | 7.75 | 13.42 | M3 |
| 3 | -7.75 | 13.42 | M3 |
| 4 | -15.5 | 0 | M3 |
| 5 | -7.75 | -13.42 | M3 |
| 6 | 7.75 | -13.42 | M3 |

## Where the files are

- Pololu: [100:1 Metal Gearmotor 37Dx57L mm 12V (#4745)](https://www.pololu.com/product/4745) — web — Publisher's page; dimensions are facts
- Pololu: [Dimensions of the 37D metal gearmotors (PDF)](https://www.pololu.com/file/0J1704/37d-metal-gearmotors-dimension-diagram.pdf) — web — Publisher's page; dimensions are facts

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

Index: https://xemstudio.com/files/hardware/pololu-37d-metal-gearmotor/index.json

- pololu-37d-metal-gearmotor: [STEP](https://xemstudio.com/files/hardware/pololu-37d-metal-gearmotor/pololu-37d-metal-gearmotor.step) · [STL](https://xemstudio.com/files/hardware/pololu-37d-metal-gearmotor/pololu-37d-metal-gearmotor.stl) — Pololu 37D metal gearmotor (100:1, #4745): Ø36.8 body, 6 mm shaft and M3 face-mount holes

## Questions

**What is the Pololu 37D mounting-hole pattern?**

Six M3 tapped holes on a Ø31.0 mm bolt circle in the gearbox face, max 3.0 mm screw engagement.

**What shaft does the 37D have?**

Ø6.0 mm D-shaft, 16.0 mm long, from a Ø12.0 × 6.0 mm boss.

**How long is the 37D gearmotor?**

For 100:1: 57.0 mm body plus 22.0 mm boss and shaft, 79.0 mm overall; shorter ratios have shorter gearboxes.

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- [Metric shafts Ø3 to Ø10 with D-flats and clip grooves](https://xemstudio.com/objects/metric-shafts/)
- [Socket head cap screws, M2–M8 (ISO 4762 / DIN 912)](https://xemstudio.com/objects/socket-head-cap-screws-metric/)