# Bevel pinion, module 1.5, 20 teeth for a 30-tooth wheel at 60° shaft angle, spherical involute

> What are the dimensions of a module 1.5, 20-tooth bevel gear?

- Category: Hardware › Mechanism parts
- Kind: Modern device
- Basis: Xem Studio design following Brown's figure (1868); true size, no printing allowance
- Page: https://xemstudio.com/objects/bevel-gear-m1-5-20t-for-30t-60deg/ · JSON: https://xemstudio.com/api/geometry?object=bevel-gear-m1-5-20t-for-30t-60deg · Plain text: https://xemstudio.com/objects/bevel-gear-m1-5-20t-for-30t-60deg/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files Xem Studio Design License (free to use and sell from, not to redistribute as files: https://xemstudio.com/license/)
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

## Overall (mm)

| length | width | height |
|---|---|---|
| 32.73 | 32.73 | 23.09 |

**Exact dimensions.** True size, with no printing tolerance added.

## Notes

- Straight bevel gear, module 1.5 at the large end, 20 teeth, for a 30-tooth mate at 60° shaft angle: pitch cone angle 23.41°, cone distance 37.75 mm, pitch Ø30, face width 12.6 mm, Ø6 bore, Ø16.99 hub.
- Teeth are exact spherical involutes (base cone sin γb = sin δ · cos 20°), converging to the pitch apex: each flank is a cone from the apex over the spherical involute, so two such gears roll with line contact at every position; ends are spheres centred on the apex (radii A0 and A0 − F). Addendum m, dedendum 1.25 m at the large end.
- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

## Sizes

| dimension | value |
|---|---|
| module (large end) | 1.5 |
| teeth | 20 (mate 30) |
| shaft angle | 60° |
| pitch cone | 23.41° |
| cone distance A0 | 37.75 mm |
| face width | 12.6 mm |
| pitch Ø | 30 mm |
| tip Ø | 32.73 mm |
| bore | Ø6 |
| apex to back of hub | 45.75 mm |

## Where the files are

- Henry T. Brown (1868, public domain): [Five Hundred and Seven Mechanical Movements — scan on archive.org](https://archive.org/details/fivehundredseven00browiala) — web — Publisher's page; dimensions are facts
- 507movements.com: [Brown's movement No. 25: figure, his text and an animation](https://507movements.com/mm_025.html) — web — Publisher's page; dimensions are facts
- Xem Studio: [drawing](https://xemstudio.com/objects/oblique-bevel-gears-mechanism/) — web — Publisher's page; dimensions are facts

## Free STEP/STL (1 parts, Xem Studio Design License, Xem Studio)

Index: https://xemstudio.com/files/hardware/bevel-gear-m1-5-20t-for-30t-60deg/index.json · license: https://xemstudio.com/files/hardware/bevel-gear-m1-5-20t-for-30t-60deg/LICENSE.md

- bevel-gear-m1-5-20t-for-30t-60deg: [STEP](https://xemstudio.com/files/hardware/bevel-gear-m1-5-20t-for-30t-60deg/bevel-gear-m1-5-20t-for-30t-60deg.step) · [STL](https://xemstudio.com/files/hardware/bevel-gear-m1-5-20t-for-30t-60deg/bevel-gear-m1-5-20t-for-30t-60deg.stl) — gear, pitch apex at the origin, axis +Z, a tooth on +X

## Questions

**What are the dimensions of a module 1.5, 20-tooth bevel gear?**

Straight bevel gear, module 1.5 at the large end, 20 teeth, for a 30-tooth mate at 60° shaft angle: pitch cone angle 23.41°, cone distance 37.75 mm, pitch Ø30, face width 12.6 mm, Ø6 bore, Ø16.99 hub.

## Fits with

- [Bevel gears for shafts at an oblique angle (60°), 20 : 30](https://xemstudio.com/objects/oblique-bevel-gears-mechanism/)