Barrel Zinc Plating, Nickel Chrome Plating, Electroplating, Trivalent Chromium Plating, Bronze Plating, Plating Services, Signal Plating, Chattanooga, Tennessee; Automatic zinc barrel plating. Zinc barrel plating includes clear & yellow chromate, rack nickel-chrome plating provides nickel only or chrome over nickel. Processing parts measuring up to 9.5 ft. long, 4 ft. high and 30 in. wide; Additional Automatic Zinc Barrel Plating details ...