We are trying to find out what type of wire is used in this device. We repaired several with .008-.009 E guitar string wire, and the wire burned through in a month or so. We know this is not the correct wire. Does anyone know what the correct wire is for these? I doubt piano wire is correct either. We are going to repair one using tungsten wire and see how it lasts, before doing the others. The size .008-.009 is about right as the cleaning beads work on this size wire. Any knowledge on this would be appreciated.