A ‘Revolution’ in Chrome Barrel Plating
Pavco’s Hex-A-Gone Revolution trivalent coating option captures the advantages of both chrome and barrel processing.
The range of products we come into contact with every day that have a chrome finish is impressive: virtually everything, it might seem, from kitchen utensils to tools to automotive trim. Even if the base material is plastic instead of metal, the decorative chromium coating makes it look like metal and feel like metal, and maybe most importantly, makes it resistant to corrosion.
Pavco Inc.’s latest decorative chrome plating process addresses two of the most common complaints about applying these types of finishes to smaller parts like the sockets pictured above: it is inefficient and tedious. Hex-A-Gone Revolution allows for bulk processing of these types of parts, producing the quality of rack plating in less-labor-intensive barrel production.
The material and method of choice for that chrome look traditionally has been hexavalent chromium applied to parts on racks. Although it provides corrosion resistance and aesthetic appeal, the hex chrome formulation has its own drawbacks, including well-documented health and environmental concerns, but it’s also hard to get full coverage on parts with rack plating.
“Rack marks are a problem for rack platers,” says Matt Stauffer, technical director for the Charlotte, North Carolina, company. “Generally, when something is chrome-plated, you can tell how it was racked by the rack marks. There are voids in the coating, because that’s where the parts had to make contact with the rack. These areas then also become more susceptible to corrosion.”
When a part is barrel-plated, there obviously are no rack marks. “In the end, customers are getting full coverage on their parts instead of areas of bare steel or dark contact marks that they have to deal with,” Stauffer says. “Full coverage inside of a socket is not something that rack chrome platers are used to.”
Plus, parts like the sockets are just difficult to rack. Barrel plating is less labor-intensive, leading to not only higher levels of efficiency, but also reduced costs. “With a barrel process, people can reconsider finishing parts overseas, where labor is cheaper, and have them done here in the U.S.,” he says.
Some shops have tried switching from rack chrome plating to non-chrome barrel processes using tin-nickel and tin-cobalt, but those coatings have weaknesses as well. “They don’t look like chrome, they’re not hard like chrome, and they don’t have the same corrosion protection as chrome,” Stauffer points out.
After years of research, Pavco has come up with a formulation that provides the hardness, color values and corrosion protection of trivalent chrome, but with improved thickness distribution and covering power over hex chrome. Hex-A-Gone Revolution can achieve bright parts with a coating thickness ranging to 0.40 microns, or even a little thicker, he says.
Of course, there are some limitations to the size of parts that can be barrel plated, but Stauffer says Pavco has had success with parts as long as 12 inches. “Essentially, things that you would conventionally barrel plate in other coatings are now possible in chrome,” he says.
Charlotte, North Carolina / 800-321-7735 / pavco.com
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