fingerjoint

Finger joint, also known as a box joint, is a woodworking joinery technique that forms a strong corner by interlocking a series of rectangular fingers cut into the ends of two pieces. The fingers mesh like interlocking teeth, and when glued, create a large continuous glue surface that resists pulling apart and helps align parts during assembly.

Manufacture typically involves precisely cutting alternating rectangular fingers and notches with a router, table saw with a jig, or a milling machine. The pieces are pressed together with glue and clamped until the adhesive cures. The interlocking pattern distributes stress along the joint and makes it well suited for long, square corners such as boxes, drawers, and cabinet sides.

Key characteristics include uniform finger width and spacing, which are chosen based on stock thickness. Common finger widths range from about 1/4 to 3/8 inch (6–10 mm) for small boxes, with larger stock using correspondingly wider fingers. The joint is essentially a decorative as well as structural element, visible on the exterior of the assembly and offering substantial gluing surface.

Variants and applications: the joint is often called a box joint when used at corners of boxes and casework. Through joints extend across the full thickness of the stock, while stopped or blind versions end before the opposite face. Finger joints are widely used in crate and cabinet construction, hobby projects, and any application requiring strong, square corners with good glue area.