# Recoil anchor for the 30-tooth Ø50 escape wheel

> What is a recoil anchor?

- 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/recoil-anchor-for-30t-d50/ · JSON: https://xemstudio.com/api/geometry?object=recoil-anchor-for-30t-d50 · Plain text: https://xemstudio.com/objects/recoil-anchor-for-30t-d50/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); linked files under their publishers' licenses
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

## Overall (mm)

| length | width | height |
|---|---|---|
| 44.96 | 25.47 | 3.0 |

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

## Notes

- 3 mm anchor pivoting on a Ø3 pin 35.36 mm above the escape wheel's centre, its two pallets spanning 7½ teeth (90°), each pallet 1.6 mm thick with its impulse face at the deep end. The locking faces are straight, their deep ends 0.3 mm off the pivot circle, so the swinging anchor pushes the wheel back a little after locking: the recoil.
- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

## Sizes

| dimension | value |
|---|---|
| pivot above wheel centre | 35.36 mm |
| span | 7½ teeth (90°) |
| pallet thickness | 1.6 mm |
| pivot hole | Ø3 |
| thickness | 3 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. 288: figure, his text and an animation](https://507movements.com/mm_288.html) — web — Publisher's page; dimensions are facts
- Xem Studio: [drawing](https://xemstudio.com/objects/recoil-anchor-escapement-mechanism/) — web — Publisher's page; dimensions are facts

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

Index: https://xemstudio.com/files/hardware/recoil-anchor-for-30t-d50/index.json

- recoil-anchor-for-30t-d50: [STEP](https://xemstudio.com/files/hardware/recoil-anchor-for-30t-d50/recoil-anchor-for-30t-d50.step) · [STL](https://xemstudio.com/files/hardware/recoil-anchor-for-30t-d50/recoil-anchor-for-30t-d50.stl) — anchor, z 0..3, pivot at (0, 35.36)

## Questions

**What is a recoil anchor?**

3 mm anchor pivoting on a Ø3 pin 35.36 mm above the escape wheel's centre, its two pallets spanning 7½ teeth (90°), each pallet 1.6 mm thick with its impulse face at the deep end. The locking faces are straight, their deep ends 0.3 mm off the pivot circle, so the swinging anchor pushes the wheel back a little after locking: the recoil.

## Fits with

- [Recoil anchor escapement: escape wheel and anchor](https://xemstudio.com/objects/recoil-anchor-escapement-mechanism/)