I usually just go over it , that's all. Now back to your dilemma, I guess you have disassembled the lock. If it's a standard Siler,flat faceted, Take the pan off. And frizzen. Polish these parts separately, if you have done that good,sorry. Now the swirl marks that you see are probably from doing this with the abrasive in your hands taking short fast strokes that have a tendency not to follow the direction constantly and not using a backer. I polish my plates by holding the plate in my hand, and using the backer with the abrasive clamped in the vise, or even on the counter/ work bench. I also wear my headset binoculars, because I can't see that well.This way you are more in control and will be taking long strokes. For the pan I have these sanding sticks.You can get them from Woodcraft. They come with little belts that fit over this sticks alittle shorter than a unsharpened pencil.The grits of the fine set start at 120,240,360,400,600 grits.Great care getting the little details under the pan, but being so small of a surface they go quick. They are also great for the flats of the pan, as well as the contours of the cock. Do the bevel edges first then the flays to clean any slightly clipped corners. Polishing a lock takes awhile, it's not something that you want to blow through. Bill Shipman is noted for crisp lines on ALL his work, both metal and wood. He is quite the master.Hope this bailed you out some, ...Geo.