A steady rest has a body juxtposable with a workpiece rotatable about a workpiece axis. Two arm elements are pivoted on the body and carry outer rollers radially engageable with the workpiece. A center element shiftable on the body in a straight line generally radially of the axis carries a center roller engageable radially with the workpiece. The rollers are angularly spaced about the workpiece. An electric actuator mounted on the body is connected by a transmission to the elements for displacing the respective roller radially relative to the workpiece.