# Dovetail halving joint (dovetail lap)

> What are the proportions of a dovetail halving joint?

- Category: Joinery › Lap & halving joints
- Kind: Hardware
- Basis: Xem Studio design — geometry computed in the generator from traditional proportions
- Page: https://xemstudio.com/objects/dovetail-halving-joint/ · JSON: https://xemstudio.com/api/geometry?object=dovetail-halving-joint · Plain text: https://xemstudio.com/objects/dovetail-halving-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 |
|---|---|---|
| 80.0 | 70.0 | 20.0 |

**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).
- A T-lap whose lap is dovetail-shaped, so the end member cannot pull out of the cross member.
- Print both parts flat, lap face up.

## Sizes

| dimension | value |
|---|---|
| stock | 20 × 20 mm square |
| parts | cross member, end member |
| tail | 12 mm at the shoulder → 18.67 mm at the end, 20 mm long |
| slope | 1:6 (9.46°) |
| depth | 10 mm (half) |
| assembles | the end member drops in from above |
| holds | pull-out along the end member, and racking |

## 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/dovetail-halving-joint/index.json · license: https://xemstudio.com/files/hardware/dovetail-halving-joint/LICENSE.md

- dovetail-halving-joint-cross-member: [STEP](https://xemstudio.com/files/hardware/dovetail-halving-joint/dovetail-halving-joint-cross-member.step) · [STL](https://xemstudio.com/files/hardware/dovetail-halving-joint/dovetail-halving-joint-cross-member.stl) — Through member: dovetail socket in the top half
- dovetail-halving-joint-end-member: [STEP](https://xemstudio.com/files/hardware/dovetail-halving-joint/dovetail-halving-joint-end-member.step) · [STL](https://xemstudio.com/files/hardware/dovetail-halving-joint/dovetail-halving-joint-end-member.stl) — End member: half-depth dovetail at its end
- dovetail-halving-joint-assembled: [STEP](https://xemstudio.com/files/hardware/dovetail-halving-joint/dovetail-halving-joint-assembled.step) · [STL](https://xemstudio.com/files/hardware/dovetail-halving-joint/dovetail-halving-joint-assembled.stl) — All parts in their assembled position (each part its own solid)

## Questions

**What angle is a dovetail?**

1:6 (9.46°) here, the usual slope for strong joints; 1:8 (7.1°) is common in hardwood.

## Fits with

- [Tee halving joint (T-lap)](https://xemstudio.com/objects/tee-halving-joint/)
- [Through dovetail joint](https://xemstudio.com/objects/through-dovetail-joint/)
- [Ari kake (dovetail beam housing)](https://xemstudio.com/objects/ari-kake-dovetail-housing/)