# Ratchet feed arm, pawl pivot at 30 mm, Ø5 hub

> What is a ratchet feed arm?

- 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/ratchet-feed-arm-30/ · JSON: https://xemstudio.com/api/geometry?object=ratchet-feed-arm-30 · Plain text: https://xemstudio.com/objects/ratchet-feed-arm-30/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 |
|---|---|---|
| 77.0 | 14.0 | 5.0 |

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

## Notes

- Lever that swings on the ratchet wheel's Ø5 shaft and carries the feed pawl on a Ø3 pin 30 mm out, with a 40 mm handle beyond: rocking it to and fro steps the Ø40, 24-tooth ratchet one or more teeth per stroke.
- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

## Sizes

| dimension | value |
|---|---|
| hub | Ø14, Ø5 bore |
| pawl pivot | Ø3 at 30 mm |
| handle | 40 × 10 mm |
| thickness | 5 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. 225: figure, his text and an animation](https://507movements.com/mm_225.html) — web — Publisher's page; dimensions are facts
- Xem Studio: [drawing](https://xemstudio.com/objects/ratchet-feed-lever-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/ratchet-feed-arm-30/index.json

- ratchet-feed-arm-30: [STEP](https://xemstudio.com/files/hardware/ratchet-feed-arm-30/ratchet-feed-arm-30.step) · [STL](https://xemstudio.com/files/hardware/ratchet-feed-arm-30/ratchet-feed-arm-30.stl) — arm, z 0..5, pawl pivot on +X

## Questions

**What is a ratchet feed arm?**

Lever that swings on the ratchet wheel's Ø5 shaft and carries the feed pawl on a Ø3 pin 30 mm out, with a 40 mm handle beyond: rocking it to and fro steps the Ø40, 24-tooth ratchet one or more teeth per stroke.

## Fits with

- [Ratchet wheel stepped by a swinging pawl lever](https://xemstudio.com/objects/ratchet-feed-lever-mechanism/)