jointer

A jointer is a woodworking machine used to create flat surfaces along a board’s length and to produce true, square edges. In its modern form it consists of a flat bed with an infeed and outfeed table, a cutterhead beneath the bed, and a fence to guide stock. The cutterhead removes material as the stock is pushed across the bed, leaving a flat, straight reference face.

Two broad categories exist: power jointers and hand jointers. A power jointer is a stationary machine commonly used in shops, offering cutterheads with rotating knives or inserts. A hand jointer, or jointer plane, is a traditional tool used with hand pressure to shave surfaces and edges. Modern power jointers come in widths such as 6, 8, or 12 inches and longer beds for longer stock.

Typical use is to flatten one face and to square and edge-joint the opposite edge. After a face is flattened, the board is run along the fence to create a straight, square edge. The resulting edge then provides a true reference for glue-ups. The board can then be finished on a thickness planer to achieve uniform thickness.

Safety and maintenance: ensure proper blade depth, align the fence parallel to the bed, and keep the knives sharp. Use push blocks and guards to keep hands clear of the cutterhead and avoid kickback. Regular maintenance includes cleaning the tables, checking fence alignment, and servicing the cutterhead.