When constructing a mortise and tenon joint, the mortise should be slightly deeper than the

• A. Tenon
• B. Shoulder
• C. Dowel
• D. Mortise

Answer: (A)

The main idea here is that the depth relationship between the mortise and the tenon affects fit and assembly. The mortise should be slightly deeper than the tenon so the tenon can fully insert and seat inside the mortise while leaving a small amount of space for glue and for the joint to pull tight under clamp. If the mortise isn’t deep enough, the tenon can bind, preventing the shoulders from seating flush and potentially stressing the stock. If it’s too deep, the joint may feel loose or lack strong shoulder contact. By making the mortise a touch deeper than the tenon, you ensure the joint sits fully, with solid shoulder contact and adequate glue area.