Library › Joinery › Lap & halving joints ·

Dovetail halving joint (dovetail lap)

Name: Dovetail halving joint (dovetail lap) dimension sheet
Creator: Xem Studio
License: https://creativecommons.org/licenses/by/4.0/

What are the proportions of a dovetail halving joint? · Hardware · basis: Xem Studio design — geometry computed in the generator from traditional proportions

Also called: dovetail halving joint, dovetail lap joint, dovetail half lap, lapped dovetail tee, junta cola de milano a media madera, Schwalbenschwanzblatt

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

length: 80.0 mm
width: 70.0 mm
height: 20.0 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).
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.

Dovetail halving joint size chart

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

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

dovetail-halving-joint-cross-member	Through member: dovetail socket in the top half	STEP · STL
dovetail-halving-joint-end-member	End member: half-depth dovetail at its end	STEP · STL
dovetail-halving-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=dovetail-halving-joint