# Pantograph linkage (2:1 copier)

> How does a pantograph scale a drawing?

- Category: Mechanisms › Linkages
- Kind: Hardware
- Basis: Xem Studio drawing; classic mechanism (Brown No. 246)
- Page: https://xemstudio.com/objects/pantograph-linkage/ · JSON: https://xemstudio.com/api/geometry?object=pantograph-linkage · Plain text: https://xemstudio.com/objects/pantograph-linkage/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/)

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

## Notes

- Four bars pinned as a parallelogram with the fixed pivot, tracer and pen on one straight line: pen travel = tracer travel × k (k = 2 here).
- Moving the pivots along the arms changes k; swapping tracer and pen reduces instead of enlarges. The line pivot–tracer–pen must stay straight for the copy to be true.
- Also used in scissor lifts, sewing-machine and engraving copiers.
- Parts (each has its own page): pantograph-arms-200-100, pins-3mm. Brown's movement No. 246 shows it (1868).

## Sizes

| parameter | value |
|---|---|
| scale k | 2 : 1 |
| arms | 200 / 100 mm |
| pins | Ø3 |

## 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

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

Index: https://xemstudio.com/files/hardware/pantograph-linkage/index.json

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

## Questions

**How does a pantograph scale a drawing?**

Four bars pinned as a parallelogram with the fixed pivot, tracer and pen on one straight line: pen travel = tracer travel × k (k = 2 here).

## Fits with

- [Pantograph arms, 200 and 100 mm (set of four)](https://xemstudio.com/objects/pantograph-arms-200-100/)
- [Crank and wrist pins Ø3 × 12, 16, 19, 20 and 23](https://xemstudio.com/objects/pins-3mm/)