socket 5 during milling in fig7 b the side view of the cap milling tool of fig7 a is outlined moreover the tip of a spot welding electrode 6 and the axis of rotation dotted line are indicated in fig7 b during the milling operation the cap milling tool rotates about the tip of the spot welding electrode 6 which itself does not rotate so that the milling edge 1 removes material from the tip of the spot welding electrode 6 the mounting socket 5 mainly serves as guide for the spot welding electrode 6 on the side facing away from the milling edge 1 typically the axis of rotation of the cap milling tool coincides with the axis of symmetry of the spot welding electrode 6 to be machined the milling cutter can also be designed such that the milling element comprises two milling edges so that both electrodes of one welding gun are machined simultaneously and with the same milling element in fig7 b the second milling edge would be arranged to be directed downwards the mounting socket 5 can then also be correspondingly designed for receiving two electrodes in fig7 b from above and from the bottom for example another approximately half round depression can be provided from the bottom when the electrodes are being subsequently machined with the electrode milling cutter the electrode can be pressed against it with a force of 1 kn to 2 5 kn machining time can be between 0 5 and 3 0 seconds in subsequent machining.