A cutter for a cutting unit used in cutting apparatus suitable for creating tunnels or subterranean roadways. The cutter includes a disc body having an underside, an upper side arranged substantially opposite to the underside, and a radially peripheral part. A plurality of buttons for abrading rock are mounted in the radially peripheral part of the disc body and protrude outwardly therefrom to engage rock during an undercutting operation, wherein at least some of the buttons have a cutting part having a dome-shaped cutting surface.

A cutter for a cutting unit used in cutting apparatus suitable for creating tunnels or subterranean roadways. The cutter includes a disc body having an underside, an upper side arranged substantially opposite to the underside, and a radially peripheral part. A plurality of buttons for abrading rock are mounted in the radially peripheral part of the disc body and protrude outwardly therefrom to engage rock during an undercutting operation, wherein at least some of the buttons have a cutting part having a dome-shaped cutting surface.

A cutter assembly for an undercutting machine for cutting a rock workface and a method of assembling a cutter assembly is provided. The cutter assembly includes a shaft mountable on the machine with one end extending from the machine, and a cutter device arranged in connection to the extended end of the shaft. The cutter device is connected releasably and rotationally rigid to the shaft with a locking arrangement. The locking arrangement includes a first locking device arranged to transfer substantially axial loads, and a second locking device arranged to transfer substantially radial loads.

A cutter assembly for an undercutting machine for cutting a rock workface and a method of assembling a cutter assembly is provided. The cutter assembly includes a shaft mountable on the machine with one end extending from the machine, and a cutter device arranged in connection to the extended end of the shaft. The cutter device is connected releasably and rotationally rigid to the shaft with a locking arrangement. The locking arrangement includes a first locking device arranged to transfer substantially axial loads, and a second locking device arranged to transfer substantially radial loads.