Something you might try if all else fails, and before drilling, is Reverse Electrolysis. I have used this technique many times in the past for restoration of artifacts which were badly oxidized or rusted with great success. What you would need for a small knob is the following:
1) A small metal pan with sides high enough to immerse the knob in liquid. 2) Sodium Carbonate (sodium hydroxide works best, however may be too caustic for the knob and remove the finish). Sodium Carbonate aka "washing power" should do fine. 3) Water 4) Small auto battery charger w/short circuit protection. 3 to 10 amps.... Mix about 1/8 cup of the washing powder with a gallon of water and fill the pan enough to cover the knob, or at least the metal insert and set screw. Attach the positive (+) to the metal pan and the negative lead to the set screw. Be sure you don't reverse this, as it will actually rust the iron even more if you do! Also make sure the point where the connection is made with the metal insert does not touch the metal pan! Turn on the charger and you should see some bubbling action coming from the set screw. If not, you either don't have a good connection, or you need to add some more washing powder. Let it sit and work for a day or so, but keep an eye on the knob finish, as I'm not certain what it will do. The electrical charge should have no effect on the knob, but the washing powder might, over time. The process should break down and dissolve ALL rust, and free the set screw from the brass. Again, be sure the (+) is connected to the metal pan and the (-) is attached to the set screw! Not sure how you can get a connection to the set screw, but maybe an allen wrench stuck into it would serve as a good connector. Brian / w5ami ______________________________________________________________ AMRadio mailing list List Rules (must read!): http://w5ami.net/amradiofaq.html List Home: http://mailman.qth.net/mailman/listinfo/amradio Partner Website: http://www.amfone.net Help: http://mailman.qth.net/mmfaq.html Post: mailto:[email protected] To unsubscribe, send an email to [EMAIL PROTECTED] with the word unsubscribe in the message body.
