Låsfogar

Låsfogar is a term used in carpentry and joinery to describe joints that connect two pieces of material with a mechanical locking feature. The word combines the Swedish terms for lock (lås) and joint (fog). Låsfogar are designed to resist separation and to provide accurate alignment without relying solely on adhesive.

Construction and function: Låsfogar use complementary profiles milled into the edges of the workpieces so that, when pressed together, they form a mechanically interlocked connection. Often, glue is applied to increase strength, and additional elements such as dowels, pins, wedges, or splines may be added to prevent movement and to boost tensile or shear strength. The exact geometry is chosen to balance ease of fabrication with the expected service loads and environmental conditions.

Variants and examples: Common implementations include finger joints (box joints) and dovetail-type locking joints, both of which offer broad gluing surfaces and good resistance to pulling forces. Other locking-edge joints may involve rebates, rebates with pins, or angled cam-like profiles. The selection depends on factors such as wood species, thickness, grain direction, and whether the joint will be exposed.

Applications and advantages: Låsfogar are used in furniture, cabinetry, and light to medium timber construction where strong edge-to-edge connections are required. They provide good alignment, distribute stress over a large area, and can be produced consistently in factory settings. They may require precise milling and careful consideration of wood movement due to humidity, to maintain fit over time.

See also: Joint (woodworking), Finger joint, Box joint, Dovetail joint, Mortise and tenon.