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Box joint (finger joint)

Name: Box joint (finger joint) dimension sheet
Creator: Xem Studio
License: https://creativecommons.org/licenses/by/4.0/

How wide are the fingers in a box joint? · Hardware · basis: Xem Studio design — geometry computed in the generator from traditional proportions

Also called: box joint, finger joint, comb joint, box joint dimensions, finger joint width, 3d printed box joint, junta de caja, unión de dedos, Fingerzinken, Zinkenverbindung gerade

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

length: 90.0 mm
width: 60.0 mm
height: 90.0 mm

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).
Square interlocking fingers, each as wide as the board is thick. Simple, strong, prints cleanly flat.

Box joint size chart

dimension	value
stock	10 mm boards, 60 mm wide
parts	board a, board b
fingers	10 mm wide, 10 mm long (one board thickness), 6 in all
assembles	one board drops onto the other
holds	racking, with a large glue area; pin it or glue it against pulling apart

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Xem Studio

Joinery design (geometry computed in the generator from traditional proportions)

web

Xem Studio design

Free files

★ Free files 3 parts. Xem Studio design: free to use, print and sell things from; not to be republished as files. Xem Studio Design License. index.json

box-joint-board-a	Board A: three fingers	STEP · STL
box-joint-board-b	Board B: three fingers, offset by one	STEP · STL
box-joint-assembled	All parts in their assembled position (each part its own solid)	STEP · STL

Let your AI pull this. Add https://xemstudio.com/mcp to Claude, ChatGPT, Cursor or any MCP client (free, no account, one minute) and it can look up exact sizes, mating fits and free STEP/STL from every chat.

Set it up →

Plain text: sheet.txt · JSON: /api/geometry?object=box-joint