Rechromed bumpers for used cars were available years ago (and may still be available) with just nickel and chrome. The result was not satisfactory, and especially in the Northeast subject to rapid and destructive rust. Acid copper, was always used for heavy pitting, and as a means to repair rough pieces. Plate acid copper, buff and polish until the desired surface was achieved. Quite frankly, if a plater asked me if I wanted copper first, I would question the overall quality of his product.
