# Mangle wheel and pinion: continuous rotation to reciprocating rotation

> How does a mangle wheel reverse itself?

- Category: Mechanisms › Intermittent motion
- Kind: Hardware
- Basis: Xem Studio design following Brown No. 36 (1868)
- Page: https://xemstudio.com/objects/mangle-wheel-and-pinion-mechanism/ · JSON: https://xemstudio.com/api/geometry?object=mangle-wheel-and-pinion-mechanism · Plain text: https://xemstudio.com/objects/mangle-wheel-and-pinion-mechanism/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/)

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

## Notes

- A pinion turning always the same way drives a wheel whose pins stand in a circle with a gap. Running outside the pins it turns the wheel one way; at the gap it slides round the end pin (its shaft moves in a radial slot) and runs inside the pins, turning the wheel back: continuous rotation becomes back-and-forth rotation.
- Here 27 pins on a 40 mm radius (30-position pitch, gap of 3) and a 9-tooth pinion of 12 mm pitch radius: centres 52 mm apart outside, 28 mm inside, so the wheel turns 0.3 × pinion speed — the same both ways because one pin circle serves both sides. Drawn running outside.
- Brown's No. 36 (mangle wheel and pinion, with the pinion shaft vibrating in a slot).
- Parts (each has its own page): mangle-pin-wheel-r40-27-pins, mangle-pinion-9t-for-pins-r40, mangle-slot-bar-r28-52, dowel-pins-metric, linear-shafts-h6.
- Brown's movement No. 36 (1868) shows it; this model is a Xem Studio design following his figure, every part at true size.

## Sizes

| parameter | value |
|---|---|
| pins | 27 × Ø4 on R40 |
| pinion | 9 T, pitch R12 |
| centres | 52 (outside) / 28 (inside) mm |
| wheel swing | ≈ 300° each way |

## 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. 36: figure, his text and an animation](https://507movements.com/mm_036.html) — web — Publisher's page; dimensions are facts

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

Index: https://xemstudio.com/files/hardware/mangle-wheel-and-pinion-mechanism/index.json · license: https://xemstudio.com/files/hardware/mangle-wheel-and-pinion-mechanism/LICENSE.md

- mangle-wheel-and-pinion-mechanism-assembly: [STEP](https://xemstudio.com/files/hardware/mangle-wheel-and-pinion-mechanism/mangle-wheel-and-pinion-mechanism-assembly.step) · [STL](https://xemstudio.com/files/hardware/mangle-wheel-and-pinion-mechanism/mangle-wheel-and-pinion-mechanism-assembly.stl) — Assembled mechanism, all parts placed at one pose (STEP keeps each part separate)

## Questions

**How does a mangle wheel reverse itself?**

A pinion turning always the same way drives a wheel whose pins stand in a circle with a gap. Running outside the pins it turns the wheel one way; at the gap it slides round the end pin (its shaft moves in a radial slot) and runs inside the pins, turning the wheel back: continuous rotation becomes back-and-forth rotation.

## Fits with

- [Mangle (pin) wheel: Ø96 × 6 disc with 27 Ø4 × 12 pins on R40, gap of 3](https://xemstudio.com/objects/mangle-pin-wheel-r40-27-pins/)
- [Mangle-wheel pinion, 9 teeth, for Ø4 pins on R40 (cut for both sides of the pin row)](https://xemstudio.com/objects/mangle-pinion-9t-for-pins-r40/)
- [Slotted bar 80 × 20 × 6 for the mangle pinion's shaft (slot from R28 to R52)](https://xemstudio.com/objects/mangle-slot-bar-r28-52/)
- [Dowel pins, 2–6 mm (ISO 2338 / DIN 6325)](https://xemstudio.com/objects/dowel-pins-metric/)
- [Linear shafts Ø3 to Ø25 mm (h6), 100 to 1000 mm long](https://xemstudio.com/objects/linear-shafts-h6/)