Boxes, drawers, chests
Box / finger joint
Square fingers that interlock. A tablesaw jig joint, not a dovetail.
Use when
- You want a mechanical corner and you are set up to cut equal pins.
Don’t use when
- Do not call it a dovetail. It does not lock the same way.
- Keep
- Waste, hatched on the drawing
- Dimension
- Long parts are broken. The 1 in bar is true scale.
Stock
Thickness steppers move by 1/16 in, or 0.5 mm. You can type 3/4 or 1-1/8.
Sizes
| Mark | Size | Rule |
|---|---|---|
| Finger width | 1/4 in | Default 1/4 in. Use half the thickness, or the full thickness, on a narrow board |
| Fingers | 15 | An odd count, so both ends start with a finger on the same face |
| Middle finger | 1/2 in | Any leftover width goes in the middle finger so the ends stay on the layout |
| Fit | 0.002 in | 0 to 0.003 in tight for glue. Plane the fingers, not the saw setup, once a test fits |
Cut sequence
1Lay out an odd count
Fingers 1/4 in wide. 15 of them, so both ends are a finger.
Setup: The middle finger is 1/2 in if the width does not divide evenly.
2Saw and chop
Saw on the waste side. Chop from both faces. The mating board is the negative of this one.
Stop when: A corner stacks flush and the faces do not step.
3Dry-fit, then glue
Close the joint dry. Check that shoulders and faces meet, then glue. If this is a frame or a box, check both diagonals before the glue grabs.
Stop when: Dry-fit is tight with hand pressure, square, and the diagonals match.
Glue
Long grain to end grain
Strength
furniture
Movement
Finger cheeks are long grain against end grain. The count of surfaces is what holds. A good joint for plywood, where dovetails chip.