Abstract: An attachment device for a woodworking plane is provided to enable said plane to accurately cut end surfaces of wooden panels. Said end surfaces may be cut either at a right angle or at angles deviating therefrom by as much as 20.degree.. The device is attached to a plane by two mounting screws within slotted passageways. A third screw, positioned in a threaded hole above said mounting screws, is manually adjusted in association with said mounting screws to control the angle of an abutment surface disposed below the underside of the plane.