A milling device for cutting up road surfaces which includes a roller-type milling body including a rotatably-mounted spiral conveyor, a plurality of rotary cutters carried on the spiral conveyor, the rotary cutters mounted for free rotation about their respective longitudinal axes. A plurality of retaining boxes is provided, each retaining box detachably connected by at least one screw in a respective trapezoidally-shaped positive radial recess in a wall of the spiral conveyor, each retaining box having a bore hole therein for receiving a respective one of the rotary cutters. The retaining boxes each have a trapezoidally-shaped shaft part for being matingly received in the trapezoidal recess with the narrow side of the trapezoidally-shaped shaft facing towards the spiral conveyor.
A tool holder includes a body, a head, and a flange. The body is dimensioned to fit closely within a slot formed within a flight block. The head is positioned at a distal end of the body and has a recess to receive a cutting tool and hold the cutting tool in a rotationally forward orientation. The head includes a threaded bore extending from the recess to an outer surface, and a set screw positioned within the threaded bore, to selectively engage and secure a cutting tool therein. The flange is positioned adjacent the head and extends from the body in a rotationally forward direction. The flange is angled away from the cutting tool recess and to one side of the tool holder to facilitate deflection of debris away from the interface of the flight block and the tool holder and to one side of the tool holder.