A method of manufacturing of an expansion sleeve including providing a sleeve blank having axially extending material weaknesses, and forming the longitudinal slots by tearing open the material weaknesses by substantially radially expanding same. A dust-collecting portion 11 includes a cyclonic portion 14 which is approximately cylinder-shaped, having a bottom and an introducing portion 15 for introducing dust-laden airflow to the cyclonic portion 14. An armature having an outside diameter of at least 0.