Abstract: A pavement slot cutter has a mobile support adapted to advance on the pavement in a predetermined direction. A drum is mounted on the support to rotate about a horizontal, transverse axis. A motor within a hub fast on the support rotates the drums. A transversely extending casing on the drum holds a transversely extending tooth structure for reciprocation therein toward and away from the support. An undulatory cam track is formed in the hub and is engaged by a cam follower on the tooth.