# Sao tsugi (keyed rod splice)

> What is a sao tsugi joint?

- Category: Joinery › Japanese joinery
- Kind: Hardware
- Basis: Xem Studio design — geometry computed in the generator from traditional proportions
- Page: https://xemstudio.com/objects/sao-tsugi-rod-splice/ · JSON: https://xemstudio.com/api/geometry?object=sao-tsugi-rod-splice · Plain text: https://xemstudio.com/objects/sao-tsugi-rod-splice/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 |
|---|---|---|
| 140.0 | 28.0 | 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 long tenon in a long mortise, locked by keys driven across — the Japanese splice for long rods and tie beams.

## Sizes

| dimension | value |
|---|---|
| stock | 20 × 20 mm square |
| parts | male, female, key 1, key 2 |
| tenon | 8 × 8 mm, 40 mm long |
| keys | two, 4 × 4 mm, through the female member and the tenon |
| assembles | tenon in, keys driven across |
| holds | pulling apart lengthwise, firmly |

## 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 (5 parts, Xem Studio Design License, Xem Studio)

Index: https://xemstudio.com/files/hardware/sao-tsugi-rod-splice/index.json · license: https://xemstudio.com/files/hardware/sao-tsugi-rod-splice/LICENSE.md

- sao-tsugi-rod-splice-male: [STEP](https://xemstudio.com/files/hardware/sao-tsugi-rod-splice/sao-tsugi-rod-splice-male.step) · [STL](https://xemstudio.com/files/hardware/sao-tsugi-rod-splice/sao-tsugi-rod-splice-male.stl) — Male member with a long tenon
- sao-tsugi-rod-splice-female: [STEP](https://xemstudio.com/files/hardware/sao-tsugi-rod-splice/sao-tsugi-rod-splice-female.step) · [STL](https://xemstudio.com/files/hardware/sao-tsugi-rod-splice/sao-tsugi-rod-splice-female.stl) — Female member with the long mortise
- sao-tsugi-rod-splice-key-1: [STEP](https://xemstudio.com/files/hardware/sao-tsugi-rod-splice/sao-tsugi-rod-splice-key-1.step) · [STL](https://xemstudio.com/files/hardware/sao-tsugi-rod-splice/sao-tsugi-rod-splice-key-1.stl) — Square key 4 × 4 × 28 mm
- sao-tsugi-rod-splice-key-2: [STEP](https://xemstudio.com/files/hardware/sao-tsugi-rod-splice/sao-tsugi-rod-splice-key-2.step) · [STL](https://xemstudio.com/files/hardware/sao-tsugi-rod-splice/sao-tsugi-rod-splice-key-2.stl) — Square key 4 × 4 × 28 mm
- sao-tsugi-rod-splice-assembled: [STEP](https://xemstudio.com/files/hardware/sao-tsugi-rod-splice/sao-tsugi-rod-splice-assembled.step) · [STL](https://xemstudio.com/files/hardware/sao-tsugi-rod-splice/sao-tsugi-rod-splice-assembled.stl) — All parts in their assembled position (each part its own solid)

## Questions

**What holds a sao tsugi?**

The keys across the tenon: pulling apart bears on them in shear.

## Fits with

- [Kanawa tsugi (keyed hooked splice)](https://xemstudio.com/objects/kanawa-tsugi-splice/)
- [Pegged mortise and tenon joint](https://xemstudio.com/objects/pegged-mortise-and-tenon-joint/)