Abstract: A chain saw for cutting aggregate materials including a saw chain of interconnected center links and side link paris composed of heat-treated steel. Certain pairs of the side links support diamond impregnated matrix cutting blocks that are laser welded to the side links in a process where the laser beam is focused and orbited along the juncture to avoid stress risers in the steel material of the supporting side links. Drawing down of the zone adjacent the weld also is controlled to avoid stress risers. The guide bar is provided with a pattern of enclosed channels for directing water to the guide bar groove at spaced positions on the periphery of the guide bar edge for flushing away the aggregate dust generated by the cutting process. The channels are angularly directed toward the guide bar nose and have incrementally increased cross sections on progressing toward the guide bar nose to enhance the flushing operation.