How to Make Perfect Box Joints

With the box joint fingers on both boards cut, check to see how well you did by dry assembling the box joint. The joint should fit snugly but the fingers should not be too tight, and the fingers should extend just slightly past the outside face of the corresponding board.

When it's time for final assembly, simply apply a small amount of woodworking glue on all faces of the box joints on both boards, assemble the joint and clamp the boards in place.