Abstract: A band saw having a frame supporting a main shaft on which driven wheels of progressively decreasing diameter are rotatably mounted. Idler wheels are journalled on the frame and endless band saw blades are carried by the several driven and idler wheels to provide transversely spaced cutting runs along one side of the frame. Drive is transmitted to one driven wheel, thence through a system of gears to the other driven wheels to move all the cutting runs at the same speed. The driven wheels are rotatably mounted on eccentrics carried by the main shaft and the idler wheels are movable by a cam shaft arrangement relative to one another across the frame. The main shaft and cam shaft are connected by a mechanism which allows both shafts to be rotated simultaneously to shift the position of the several wheels and thus selectively adjust the spacing between the cutting runs.