Abstract: A tool for machining workpieces, having a parent body which can be expanded at least zonally, having at least one geometrically defined cutting edge projecting beyond a circumferential surface of the tool, and having a setting device influencing the radial distance of the cutting edge from the center axis of the tool. The setting device has a setting element, and an adjusting device which sets the degree of bending of the setting element. The setting element is inserted into the parent body of the tool in such a way that, when the bending of the setting element is varied, the radial distance of the cutting edge is varied.