sponningen

Sponningen is a woodworking term used in Nordic languages for a rabbet or groove cut along the edge or end of a piece of timber to receive another piece. The resulting joint is commonly used in frames, doors, cabinetry, and furniture, where it increases glue area, provides alignment, and helps conceal fasteners. A sponning is typically rectangular, with its width matching the thickness of the inserted piece and its depth determining how far the cut goes into the wood.

Producing a sponning can be done with hand tools or power equipment. Hand tools include a shoulder or rabbet plane and chisels for cleaning the corners, while powered methods include routers, table saws with dado blades, or a plough plane. The typical workflow involves marking the shoulder lines, cutting the cheeks to the desired depth, and finishing the corners for a square, clean fit. The goal is a precise, snug fit that can be held without excessive forcing, sometimes aided by a small amount of glue.

Variants of sponningen include the stopped rabbet, where the cut ends before the edge, and the through rabbet, where the notch extends across the full thickness of the workpiece. In frame-and-panel construction and similar assemblies, sponning is often paired with other joints to achieve both strength and a clean appearance. Sponningen is distinct from grooves cut into a surface to accept panels; while grooves are typically used for panels within a frame, a sponning creates an edge-wise recess that accepts a mating piece.