# Bayonet twist-lock joint

> How do you make a 3D printed bayonet mount?

- Category: Joinery › 3D-print connectors
- Kind: Hardware
- Basis: Xem Studio design — geometry computed in the generator from traditional proportions
- Page: https://xemstudio.com/objects/bayonet-twist-lock-joint/ · JSON: https://xemstudio.com/api/geometry?object=bayonet-twist-lock-joint · Plain text: https://xemstudio.com/objects/bayonet-twist-lock-joint/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 |
|---|---|---|
| 40.0 | 40.0 | 30.0 |

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

## Notes

- Woodworking joint drawn for 3D printing: the parts lock together by shape, so a print can be joined without glue or screws. Drawn at true size with the parts line to line (zero gap) in their assembled position — add your printer's fit allowance to the mating faces (your AI or slicer can do this).
- Push and twist: pins on the plug run down the straight part of the L slots and lock in the short turn — lids, lens mounts, quick-release fittings, vacuum and dust ports.

## Sizes

| dimension | value |
|---|---|
| stock | Ø40 socket, Ø32 plug |
| parts | socket, plug |
| pins | three, Ø4 mm, 120° apart |
| slot | 12 mm straight entry, then a 30° turn |
| assembles | push in, turn 30° to lock |
| holds | pulling apart; turn back to release |

## Where the files are

- Xem Studio: [Joinery design (geometry computed in the generator from traditional proportions)](https://xemstudio.com/) — web — Xem Studio design

## Free STEP/STL (3 parts, Xem Studio Design License, Xem Studio)

Index: https://xemstudio.com/files/hardware/bayonet-twist-lock-joint/index.json · license: https://xemstudio.com/files/hardware/bayonet-twist-lock-joint/LICENSE.md

- bayonet-twist-lock-joint-socket: [STEP](https://xemstudio.com/files/hardware/bayonet-twist-lock-joint/bayonet-twist-lock-joint-socket.step) · [STL](https://xemstudio.com/files/hardware/bayonet-twist-lock-joint/bayonet-twist-lock-joint-socket.stl) — Socket tube Ø40 / Ø32 bore with three L-shaped slots
- bayonet-twist-lock-joint-plug: [STEP](https://xemstudio.com/files/hardware/bayonet-twist-lock-joint/bayonet-twist-lock-joint-plug.step) · [STL](https://xemstudio.com/files/hardware/bayonet-twist-lock-joint/bayonet-twist-lock-joint-plug.stl) — Plug Ø32 with three Ø4 pins (shown locked, turned 30°)
- bayonet-twist-lock-joint-assembled: [STEP](https://xemstudio.com/files/hardware/bayonet-twist-lock-joint/bayonet-twist-lock-joint-assembled.step) · [STL](https://xemstudio.com/files/hardware/bayonet-twist-lock-joint/bayonet-twist-lock-joint-assembled.stl) — All parts in their assembled position (each part its own solid)

## Questions

**How far does a bayonet turn?**

30° here; 30–90° is common, with two to four pins.

## Fits with

- [Snap-fit cantilever joint (hook and catch)](https://xemstudio.com/objects/snap-fit-cantilever-joint/)
- [Jigsaw puzzle joint (for splitting large prints)](https://xemstudio.com/objects/jigsaw-puzzle-joint/)