Just put a decent cloth around it and open a pair of pliers up to grip it solid with the inner circular part of the pliers. That way you shouldn't have to bear down a lot so you won't scratch it and I'll bet it will come off. Then you can clean the threads up with a tad of light oil and toothbrush.
Last edited by Topgun 3006; 08-22-2011 at 07:16 PM.