# Cams lifting a stamp that drops by its own weight

> How are stamps lifted and dropped?

- Category: Mechanisms › Cams
- Kind: Hardware
- Basis: Xem Studio design following Brown No. 85 (1868)
- Page: https://xemstudio.com/objects/stamp-cam-mechanism/ · JSON: https://xemstudio.com/api/geometry?object=stamp-cam-mechanism · Plain text: https://xemstudio.com/objects/stamp-cam-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 cam on a turning shaft catches the tappet on a vertical stamp, lifts it, and lets it slip off the lobe's tip so the stamp falls by its own weight onto the work — the ore stamp and the drop hammer.
- Two lobes rising R14 → R30 over 140°: 16 mm lift, two blows per turn. The stamp's stem runs in two guide blocks 40 mm to the side of the cam shaft; drawn with the cam at 60° and the tappet resting on it.
- Brown's No. 85 (cams on a rotating shaft lifting rods that drop by gravity: stamps and hammers).
- Parts (each has its own page): stamp-cam-2-lobe-r14-r30-bore8, stamp-stem-8x8-160-tappet-head, stamp-guide-block-16x16-sq8, linear-shafts-h6.
- Brown's movement No. 85 (1868) shows it; this model is a Xem Studio design following his figure, every part at true size.

## Sizes

| parameter | value |
|---|---|
| cam | 2 lobes, 16 mm lift |
| blows per turn | 2 |
| stamp | 8 × 8 stem, 160 long |

## 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. 85: figure, his text and an animation](https://507movements.com/mm_085.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/stamp-cam-mechanism/index.json · license: https://xemstudio.com/files/hardware/stamp-cam-mechanism/LICENSE.md

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

## Questions

**How are stamps lifted and dropped?**

A cam on a turning shaft catches the tappet on a vertical stamp, lifts it, and lets it slip off the lobe's tip so the stamp falls by its own weight onto the work — the ore stamp and the drop hammer.

## Fits with

- [Two-lobe stamp cam R14 → R30, 8 thick, Ø8 bore](https://xemstudio.com/objects/stamp-cam-2-lobe-r14-r30-bore8/)
- [Stamp: 8 × 8 stem 160 long with a 48 × 10 tappet and a 16 × 30 head](https://xemstudio.com/objects/stamp-stem-8x8-160-tappet-head/)
- [Guide block 16 × 16 × 16 with an 8 × 8 slot](https://xemstudio.com/objects/stamp-guide-block-16x16-sq8/)
- [Linear shafts Ø3 to Ø25 mm (h6), 100 to 1000 mm long](https://xemstudio.com/objects/linear-shafts-h6/)