I noticed the bar magnet in my humbucker is rusted from years of playing in Hawaii. What is an easy way to remove the rust?
I would carefully remove the magnet and remember how it was taken out. There is usually a black line on one edge of the bar magnet that usually designates the North polarity and faces the stud side of the coil. Having access to a table mounted motor and fine bristle wire wheel will usually do the trick to remove unwanted debris and rust on the magnet. I would also soak the magnet in a fine oil solution such as WD-40 and wipe off before cleaning with a wire brush. The WE-40 will soften the rust making it easier to remove when buffing with the wire wheel. Also make sure you wear eye protection and avoid using gloves because the wire bristle wheel could snag them. Carefully wire brush the magnet by hand and keep loose items such as shirt sleeves, ties and long hair away from rotating motors and machinery.
