Mortises

Mortise refers to a cavity cut into a piece of material, typically wood, to receive a projecting component called a tenon. Together they form a mortise-and-tenon joint, one of the oldest and strongest methods of wood joinery. Mortises are often rectangular or square, but they may be oblong or uniquely shaped to accommodate specialized tenons. Common types include through mortises (the cavity extends completely through the piece), blind mortises (non-through), stub mortises (short), and haunched mortises (paired with a haunched tenon for alignment and strength). In frame and furniture work, mortises and tenons align across members to resist pulling and shear forces.

Cutting a mortise involves layout of the joint, removing waste with a chisel or auger, and finishing the walls for a precise fit. Tools include mortising machines, hollow-chisel mortisers, routers, chisels, and drill bits. Workpieces must be prepared to accommodate glue and, in traditional practice, sometimes drawboring with pins to enhance security. Some modern joints use loose or closed tenons, biscuits, or mechanical fasteners in conjunction with mortises.

Mortises are used in timber framing, cabinetmaking, and furniture making, contributing to joints that can be disassembled or permanent. In addition to woodworking, the term appears in hardware contexts (such as mortise locks) where a cavity is cut into a door to receive a locking mechanism. The concept emphasizes precision and wood movement considerations, ensuring a tight, durable connection.