The shoulder plane is a plane tool

Plane (tool)

A hand plane is a tool for shaping wood. When powered by electricity, the tool may be called a planer. Planes are used to flatten, reduce the thickness of, and impart a smooth surface to a rough piece of lumber or timber. Planing is used to produce horizontal, vertical, or inclined flat surfaces on...

 with a blade flush with the edges of the plane, allowing trimming right up to the edge of a workpiece. Like a rebate plane

Rebate plane

The rebate plane is a hand plane designed for cutting rebates in wood. It's a simple tool, used in many Western countries, with hundreds of years of history...

, the shoulder

Shoulder

The human shoulder is made up of three bones: the clavicle , the scapula , and the humerus as well as associated muscles, ligaments and tendons. The articulations between the bones of the shoulder make up the shoulder joints. The major joint of the shoulder is the glenohumeral joint, which...

 plane's blade extends, therefore cuts, to the full width of the tool. The shoulder plane is used to trim the shoulders and faces of tenons

Mortise and tenon

The mortise and tenon joint has been used for thousands of years by woodworkers around the world to join pieces of wood, mainly when the adjoining pieces connect at an angle of 90°. In its basic form it is both simple and strong. Although there are many joint variations, the basic mortise and tenon...

. It is used when it is necessary to trim right into the concave corner where two surfaces of the same piece of wood meet perpendicularly. It is also commonly used to clean up dadoes (housings) and tenons for joinery.

Unlike the rebate plane, the shoulder plane is intended to cut end grain. There are therefore differences between it and a rebate plane in the angles at which the iron (blade) is set.

• There is a more acute angle between the iron and the sole of the tool.
• The iron is set square across the tool rather than obliquely.
• The iron is set face down. The ground and honed bevel forming the edge is uppermost.

A shoulder plane also has a much finer set mouth, which allows finer shavings to be taken.