# Eccentric bush Ø16 × 12 with Ø6 bore offset 2.5 mm and a 50 mm lever

> How does an eccentric bush throw gears in and out of mesh?

- 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/eccentric-bush-16-bore6-e2-5-lever/ · JSON: https://xemstudio.com/api/geometry?object=eccentric-bush-16-bore6-e2-5-lever · Plain text: https://xemstudio.com/objects/eccentric-bush-16-bore6-e2-5-lever/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 |
|---|---|---|
| 58.0 | 16.0 | 12.0 |

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

## Notes

- Ø16 × 12 bush whose Ø6 bore is 2.5 mm off centre, with a 10 × 4 lever: turning it half a turn in its housing moves the axle 5 mm, more than the 2.25 mm tooth depth of module 1 gears, so the pinion swings fully in or out of mesh.
- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

## Sizes

| dimension | value |
|---|---|
| bush | Ø16 × 12 |
| bore | Ø6, 2.5 mm off centre |
| lever | 50 × 10 × 4 |

## 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. 56: figure, his text and an animation](https://507movements.com/mm_056.html) — web — Publisher's page; dimensions are facts
- Xem Studio: [drawing](https://xemstudio.com/objects/eccentric-back-gear-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/eccentric-bush-16-bore6-e2-5-lever/index.json · license: https://xemstudio.com/files/hardware/eccentric-bush-16-bore6-e2-5-lever/LICENSE.md

- eccentric-bush-16-bore6-e2-5-lever: [STEP](https://xemstudio.com/files/hardware/eccentric-bush-16-bore6-e2-5-lever/eccentric-bush-16-bore6-e2-5-lever.step) · [STL](https://xemstudio.com/files/hardware/eccentric-bush-16-bore6-e2-5-lever/eccentric-bush-16-bore6-e2-5-lever.stl) — bush, axis Z, centre at origin, bore at (-2.5, 0), z -14..-2

## Questions

**How does an eccentric bush throw gears in and out of mesh?**

Ø16 × 12 bush whose Ø6 bore is 2.5 mm off centre, with a 10 × 4 lever: turning it half a turn in its housing moves the axle 5 mm, more than the 2.25 mm tooth depth of module 1 gears, so the pinion swings fully in or out of mesh.

## Fits with

- [Gear thrown in and out of mesh by an eccentric bush (lathe back gear)](https://xemstudio.com/objects/eccentric-back-gear-mechanism/)