# Flat belt 16 × 1.5 for a Ø40 / Ø80 drive at 140 mm with a Ø30 jockey pulley (loop drawn)

> How much longer is a belt run over a jockey pulley?

- 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/flat-belt-16x1-5-jockey-drive-40-80-c140/ · JSON: https://xemstudio.com/api/geometry?object=flat-belt-16x1-5-jockey-drive-40-80-c140 · Plain text: https://xemstudio.com/objects/flat-belt-16x1-5-jockey-drive-40-80-c140/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 |
|---|---|---|
| 203.0 | 83.0 | 16.0 |

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

## Notes

- 16 × 1.5 mm belt on Ø40 and Ø80 pulleys 140 mm apart, its slack (upper) strand pressed 8 mm in by a Ø30 jockey pulley on its back: inside length 472.33 mm, 0.98 mm more than the plain open belt (471.36 mm) — the slack the jockey takes up.
- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

## Sizes

| dimension | value |
|---|---|
| width × thickness | 16 × 1.5 mm |
| inside length | 472.33 mm |
| open-belt length | 471.36 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. 5: figure, his text and an animation](https://507movements.com/mm_005.html) — web — Publisher's page; dimensions are facts
- Xem Studio: [drawing](https://xemstudio.com/objects/jockey-pulley-belt-tightener-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/flat-belt-16x1-5-jockey-drive-40-80-c140/index.json · license: https://xemstudio.com/files/hardware/flat-belt-16x1-5-jockey-drive-40-80-c140/LICENSE.md

- flat-belt-16x1-5-jockey-drive-40-80-c140: [STEP](https://xemstudio.com/files/hardware/flat-belt-16x1-5-jockey-drive-40-80-c140/flat-belt-16x1-5-jockey-drive-40-80-c140.step) · [STL](https://xemstudio.com/files/hardware/flat-belt-16x1-5-jockey-drive-40-80-c140/flat-belt-16x1-5-jockey-drive-40-80-c140.stl) — belt loop, z 2..18

## Questions

**How much longer is a belt run over a jockey pulley?**

16 × 1.5 mm belt on Ø40 and Ø80 pulleys 140 mm apart, its slack (upper) strand pressed 8 mm in by a Ø30 jockey pulley on its back: inside length 472.33 mm, 0.98 mm more than the plain open belt (471.36 mm) — the slack the jockey takes up.

## Fits with

- [Jockey (tightening) pulley engaging a slack belt](https://xemstudio.com/objects/jockey-pulley-belt-tightener-mechanism/)