Atlas offers a deep shade of hexavalent chrome which has a 7-15 micro-inch thickness.We apply our chrome over different base metals but the majority of the jobs have a bright Nickel as the last layer just before chrome plating. We can also apply the chrome directly over polished stainless and brass.Atlas also offers satin chrome or none directional matte chrome.the chrome layer is same for the show chrome or street quality chrome.
Chrome Plating Aluminium
Chrome Plating Aluminium requires an extra step to prevent the oxidation of Aluminium surface after de-greasing and before plating starts. the conventional process is to deep the Aluminium parts inside a zinc based solution for less than a minute then proceed to Strike copper or directly to Nickel plating tank.
Show Chrome VS. Street Chrome
"Show chrome" means chrome that is good enough to be on a winning entry in a car show. if We accept a job for show quality finish We would attempt to create a flawless finish.if we find large pitting or void after the polishing process is done we would start to braze or solder the pin holes one by one and sand again till we get close to perfect. another method we use is filling the smaller holes with layers of Copper. after adding each layer we buff and inspect again.This method creates an almost flawless finish that we call "Show Chrome". sometimes the base metal is close to perfect after polishing and we can achieve the show quality without any brazing or soldering. If we don't repair the surface or if we don't use several layers of Copper we call in Street quality. So street quality could be as good as a show quality if the base metal is sound.
Triple Plating and our Duplex Nickel
In general triple plating referes to three layers of Copper,Nickel and chrome.The most important issue for durable chrome plating for outdoor exposure such as on a vehicle is that it should have at least two layers of nickel plating before the chrome: namely semi-bright nickel followed by bright nickel. The reason for this involves the anodic corrosion issues. The bright nickel is anodic to the semi-bright nickel, and sacrificially protects it, spreading the corrosion forces laterally instead of allowing them to penetrate through to the steel. OEMs demand very close control of this factor, and there is a test (the Chrysler developed STEP test) which large shops run daily to insure the right potentials. Careful control of this issue is probably the principal reason that today's chrome plating greatly outlasts the chrome plating of earlier times. If a restoration shop offers only single layer nickel plating, they must apply it really really heavy if corrosion resistance is to be guaranteed, because any porosity or pinhole will doom the underlying steel.
Experts argue whether copper plating provides any additional corrosion resistance at all, but with or without copper plating, chrome on top of a single thin layer of nickel will not hold up to the severe exposure of a vehicle! Industry professionals call the two layers of nickel "duplex nickel plating", and that would be a much better term to use than "triple chrome" and such.
Chrome Electroplating OR Dipping
When it comes to chrome it is always electroplating. Chrome can not be applied by dipping. Sometimes people ask us,"Don't you just dip it in Chrome?". Well it is not dipping and it is not that easy. as a matter of fact the actual chroming process on a small piece only takes about 45 seconds but getting the piece up to that stage requires lots of efforts.
Re-chroming Pot metal Is Expensive,Why?
When you strip an old piece of chrome plated potmetal, under the plating you can see these small black pin holes. These are the damages due to corrosion. At Atlas we blast these holes first to remove the black non-conductive layer then we sent piece to polishing room. The polisher would sand a layer off (if there is enough thickness on the base metal). If the surface is free from pin holes we can proceed to plating and expect a nice finish. In most cases the surface is still covered by small or large pin holes in that case we have to braze the large holes and attempt to fill the small holes with acid Copper layers. We may end up with 3-4 layers of acid Copper and after each layer we need to go back to the polishing room and rebuff the surface. this repeated process of plating and sanding/buffing makes the restoration of potmetal expensive.
Black Chrome is a darker version of chrome due to some additive it the tank.Black chrome has a poor throwing power even less than traditional chrome tanks. This poor throwing power causes the deposits to skip the corners. Most of what we see in the market as black chrome has nothing to do with chrome. In most cases there are some layers of primer paint then a layer of Aluminium Vapor and translucent black on the top. At Atlas we have a small tank for actual black chrome on very small pieces like gun parts. for larger applications we have our method of black chrome which include traditional plating plus translucent black top coat.