A method for creating a hole for a permanent fastener that replaces a temporary fastener that fastens two adjacent workpieces. The cleaning brush head is configured to operate on at least one dirty portion to be cleaned within the reaction chamber. Using the latter, the pilot tone is output from the respective feeder cable, and is processed further in order to determine phase differences between the feeder cables. The walls of one or more adjacent cavities define one or more slots which can be shaped to receive an electronic device. The adhesive is irradiated with light to cure the adhesive and form an adhesive layer having a refractive index of 1.