When using lead free it will be experienced an increased oxidation in the wettable area of the tip. These oxidesnmust be removed regularly otherwise it will make the tip completely unwettable and not usable anymore. Whenncleaning the tip by means of the Weller WDC Dry Cleaner a special metal wool is used. First the surplus solder isnremoved by tapping the tip on the soft edge of the collector box.The final cleaning is then done by pushingnand turning the tip in the metal wool. After cleaning there is still a fine rest of solder on the tip avoiding fastnoxidation of the iron layer which is an advantage versus the cleaning by the wet sponge. The metal wool can bensoaked in flux