Abstract: A carriage on the frame of a lumber edger is driven on tracks longitudinally from one limit to another. Two motors are arranged with their corresponding output shafts coaxial and facing each other. A saw blade is mounted to each shaft. The motors are mounted to laterally extending tracks on the carriage and actuators are provided for shifting the motors, and hence, the parallel saw blades toward and away from each other so that when the saws are translated longitudinally they will rip the irregular edges from a board. A chain conveyor runs through the machine frame and transports the boards to a position under the saws with the length of the boards directed longitudinally. When a rough board arrives under the saws the lines along which the saws will cut are marked on the board with parallel laser light beams. The saws are shifted laterally until the light lines are just inside of both rough edges.