# Print-in-place: articulated chain, 6 links, 20 mm pitch

> How do you 3D print a chain that comes off the printer already linked?

- Category: 3D printing › Print-in-place mechanisms
- Kind: Hardware
- Basis: Xem Studio design: identical links on 45° cone pivots; one designed running gap of 0.40 mm
- Page: https://xemstudio.com/objects/print-in-place-articulated-chain/ · JSON: https://xemstudio.com/api/geometry?object=print-in-place-articulated-chain · Plain text: https://xemstudio.com/objects/print-in-place-articulated-chain/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 |
|---|---|---|
| 128.0 | 18.0 | 8.0 |

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

## Notes

- 3D print in place — prints already assembled, moving, in one job. Drawn at true size with no printer tolerance added; the 0.40 mm running gaps are part of the design.
- Running gap 0.40 mm per side, 0.80 mm on diameter — part of the design, drawn as is. On the 45° faces the same 0.40 mm is measured square to the face (0.57 mm along the axis).
- Bed: laid out straight, every link flat on the bed, joint axes horizontal 4 mm up; knuckles stand on their 45° feet.
- Support while printing: each joint is a fork of two knuckles whose 45° cones point inward into sockets in the next link's centre knuckle; cones on a horizontal axis stay within 45°. The plates are cut back round every knuckle so nothing of one link sits over another.
- Captured: the two opposed cones of each fork hold the next link's knuckle between them; no link can come off.
- Freeing it: bend each joint up and down by hand, link by link, then roll the chain over a finger.
- Motion: each joint bends 162.2° one way and 99.5° the other from straight (computed by turning one link against the next), so the chain wraps round a small radius and lies flat.

## Sizes

| key | value | what |
|---|---|---|
| gap_mm | 0.4 | running gap per side on every moving interface (radial, axial, under captured parts) — part of the design, not a tolerance |
| pitch_mm | 20.0 | joint to joint |
| links | 6 |  |
| chain_l_mm | 128.0 | laid straight, as printed |
| chain_w_mm | 18.0 |  |
| knuckle_d_mm | 8.0 |  |
| pin_d_mm | 5.2 | 45° cone pivot base (two per joint, from the fork into the next link) |
| plate_t_mm | 3.0 |  |
| bend_up_deg | 162.2 | each joint, from straight |
| bend_down_deg | 99.5 | each joint, the other way |

## Where the files are

- Xem Studio: [Print-in-place mechanism design (geometry computed in the generator)](https://xemstudio.com/) — web — Xem Studio design

## Free STEP/STL (7 parts, Xem Studio Design License, Xem Studio)

Index: https://xemstudio.com/files/hardware/print-in-place-articulated-chain/index.json · license: https://xemstudio.com/files/hardware/print-in-place-articulated-chain/LICENSE.md

- print-in-place-articulated-chain-assembly: [STEP](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-assembly.step) · [STL](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-assembly.stl) — The whole print as laid on the bed (6 bodies, already assembled); STEP keeps each moving body a separate solid
- print-in-place-articulated-chain-link-1: [STEP](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-link-1.step) · [STL](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-link-1.stl) — Link 1: centre knuckle with two cone sockets, fork with two 45° cones; pitch 20
- print-in-place-articulated-chain-link-2: [STEP](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-link-2.step) · [STL](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-link-2.stl) — Link 2: centre knuckle with two cone sockets, fork with two 45° cones; pitch 20
- print-in-place-articulated-chain-link-3: [STEP](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-link-3.step) · [STL](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-link-3.stl) — Link 3: centre knuckle with two cone sockets, fork with two 45° cones; pitch 20
- print-in-place-articulated-chain-link-4: [STEP](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-link-4.step) · [STL](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-link-4.stl) — Link 4: centre knuckle with two cone sockets, fork with two 45° cones; pitch 20
- print-in-place-articulated-chain-link-5: [STEP](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-link-5.step) · [STL](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-link-5.stl) — Link 5: centre knuckle with two cone sockets, fork with two 45° cones; pitch 20
- print-in-place-articulated-chain-link-6: [STEP](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-link-6.step) · [STL](https://xemstudio.com/files/hardware/print-in-place-articulated-chain/print-in-place-articulated-chain-link-6.stl) — Link 6: centre knuckle with two cone sockets, fork with two 45° cones; pitch 20

## Questions

**How are the links joined?**

Each link ends in a fork whose two knuckles carry 45° cones pointing into cone sockets in the next link's centre knuckle — no pins to insert.

**Can I make it longer?**

Repeat the link at 20 mm pitch: every link is identical (the first link's sockets and the last link's cones are simply unused).

## Fits with

- [Print-in-place: captive wheel on a printed axle (Ø40 × 12)](https://xemstudio.com/objects/print-in-place-captive-wheel-axle/)
- [Print-in-place: barrel hinge, three knuckles, folds 180° (48.8 mm)](https://xemstudio.com/objects/print-in-place-barrel-hinge-180/)
- [Print-in-place: seven-knuckle hinge on a captive through-pin (58.4 mm)](https://xemstudio.com/objects/print-in-place-multi-knuckle-hinge/)
- [Print-in-place: captive turntable with V-ridge retention (Ø80 platter)](https://xemstudio.com/objects/print-in-place-captive-turntable/)
- [Print-in-place: linear slider on a dovetail rail with end stops (100 mm)](https://xemstudio.com/objects/print-in-place-dovetail-slider/)
- [Print-in-place: captive ball joint, Ø24 ball, limited cone](https://xemstudio.com/objects/print-in-place-ball-joint/)
- [Print-in-place: push button with flexure return and click](https://xemstudio.com/objects/print-in-place-push-button-flexure/)