Once again I present to you some “Before & After” photos. These are the rotors from a Paxman French horn that came into the shop last week. The first photo shows the rotors from a double horn and as you can see there is a significant amount of bluish/green buildup on both the four rotors and the back bearings which are the pieces directly above the rotors. In the second photo, abracadabra, like magic the rotors and back bearings are clean as a whistle. Actually it’s far from magic. The rotors were scoured using a dremel with a small brass brush then they were put into a de-greaser to remove all unwanted sludge & grit and finally they go into a chemical cleaner designed to clean brass parts. The same procedure was also done to the rotor casings which are attached to the French horn itself. Next, I wipe everything down with denatured alcohol and then reassemble the horn. Nothing to it, a piece of cake, etc., etc., etc. The majority of French horns that come into my shop need this same procedure.
Paxman horns are British made and seem to be nice instruments. They are not as common in this country but they do pop up now and then.