# Stepped (speed-cone) pulley Ø50 / Ø40 / Ø30 × 20 mm steps, Ø8 bore

> What is a stepped cone 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/stepped-cone-pulley-50-40-30/ · JSON: https://xemstudio.com/api/geometry?object=stepped-cone-pulley-50-40-30 · Plain text: https://xemstudio.com/objects/stepped-cone-pulley-50-40-30/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 |
|---|---|---|
| 50.0 | 50.0 | 60.0 |

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

## Notes

- Three flat-belt steps Ø50, Ø40 and Ø30, each 20 mm wide (60 mm total), Ø8 bore. Two identical cones mounted the opposite way round keep the same belt length on each step pair (the diameters sum to 80 every time).
- Xem Studio design following Brown's figure; true size, no printing allowance (apply your own to the mating features).

## Sizes

| dimension | value |
|---|---|
| steps | Ø50 / Ø40 / Ø30 |
| step width | 20 mm |
| bore | Ø8 |

## 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. 8: figure, his text and an animation](https://507movements.com/mm_008.html) — web — Publisher's page; dimensions are facts
- Xem Studio: [drawing](https://xemstudio.com/objects/stepped-cone-pulleys-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/stepped-cone-pulley-50-40-30/index.json

- stepped-cone-pulley-50-40-30: [STEP](https://xemstudio.com/files/hardware/stepped-cone-pulley-50-40-30/stepped-cone-pulley-50-40-30.step) · [STL](https://xemstudio.com/files/hardware/stepped-cone-pulley-50-40-30/stepped-cone-pulley-50-40-30.stl) — pulley, axis Z, Ø50 step at z 0..20

## Questions

**What is a stepped cone pulley?**

Three flat-belt steps Ø50, Ø40 and Ø30, each 20 mm wide (60 mm total), Ø8 bore. Two identical cones mounted the opposite way round keep the same belt length on each step pair (the diameters sum to 80 every time).

## Fits with

- [Stepped cone pulleys (three speeds by moving the belt)](https://xemstudio.com/objects/stepped-cone-pulleys-mechanism/)