Abstract: A large diameter rock drill includes a tubular body and a central shaft longitudinally axially disposed with respect to the body. The shaft extends longitudinally axially above the top edge of the body and is attached to a drive means. A plurality of angularly spaced apart vertical plates are attached to the inside wall of the body and the shaft. Each of the plates has a lower edge which tapers downwardly and inwardly from the inside wall of the body toward the longitudinal axis of the drill near its lower end. The plates' lower edges taper downwardly and inwardly and have an array of closely packed pockets mounted thereon, each pocket receiving a drill tooth. The radially outermost pockets are affixed to vertically extending, outwardly projecting ribs on the body. The teeth face downwardly and outwardly, and are angled in a clockwise or counterclockwise direction.