The tool for producing a thread-like groove (14) in a drill hole (11) in a concrete wall (10) has a rotary percussion bit (15). The tool edge (17') is located at the tip of the rotary percussion bit. Located in a centre area is a coarse-pitch thread (18) in which balls (21, 22) engage which are arranged in a fixed position in the housing. By a percussion movement on the rotary percussion bit, a rotary and axial movement is imparted to the rotary percussion bit as a result of the coarse-pitch thread and the balls. After the thread-like groove is produced in the drill hole in the concrete, a compound anchor is inserted into the groove with the addition of a hardening compound mixture. In this way, especially good adherence of the compound anchor is obtained. <IMAGE>
