Kawai tsugite (four-way dovetail joint) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/kawai-tsugite-joint/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)
Basis: Xem Studio design — geometry computed in the generator from traditional proportions
Catalog version: 2026-10-20

Overall (mm): length 20.0, width 20.0, height 120.0
- 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).
- The joint that looks impossible: a dovetail shows on all four faces. Both pieces are straight prisms along the diagonal of the square section, so they slide together diagonally — the trick that makes it work.
- Kiyoshi Kawai's joint, made famous as the "impossible dovetail". Prints well: the faces are straight along the slide direction.

dimension  value
stock  20 × 20 mm square
parts  part a, part b
dovetails  6 → 10 mm in the diagonal section, 12 mm long (appear √2 wider on the faces)
assembles  the two pieces slide together along the diagonal of the square section
holds  pulling apart lengthwise and bending in every direction

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Xem Studio: Joinery design (geometry computed in the generator from traditional proportions) — web — Xem Studio design — https://xemstudio.com/

Free files (Xem Studio Design License, Xem Studio; STEP + STL, 3 parts): https://xemstudio.com/files/hardware/kawai-tsugite-joint/index.json
API: https://xemstudio.com/api/geometry?object=kawai-tsugite-joint