durability comparison - nickel vs. chrome

[funkmunky]

can anyone offer and input on this? Also, is there any difference between nickel and Electroless nickel, or between chrome and electroless krome? anything you have would be wonderful, as well as pics of some nickel and chrome parts. thanks! --Dave

[dadkar2]

Electroless Krome is not real chrome plating. It is an electroless nickel with a bluish tint--at least it should be. Copy Chrome is basically nickel plating with a cobalt adder to give it the blue tint. I'm not sure what adder is used with Electroless Krome.

There are many differences between electrolytic nickel and electroless nickel. In the plating industry, electrolytic nickel is often preferred for cosmetic parts intended to have a brilliant polished finish. Modern brighteners and levelers do wonders to enhance the results you get with electrolytic nickel. Electroless nickel is a workhorse finish that is often used on complex shapes with inside areas that are beyond the "throw" of electrolytic nickel. An example is a gun barrel, where you just can't get electrolytic nickel to throw. Electroless nickel will plate an inside barrel without any trouble.

The literature has it that electroless nickel can give results harder and more durable than electrolytic nickel. Some claim the hardness can compete with the hardness of real chrome plating. That is possible, but it will depend on the formulation and post heat treating processes as well.

A triple chrome cosmetic finish will offer the best of all worlds for cosmetic applications--excellent corrosion resistance and resistance to wear. Hard chrome plating alone is often used to enhance the mechanical wear resistance of gears, bearings, etc.

Triple chrome is so named because it involves three separate processes:

Copper plate
Nickel plate
Chromium plate

If you stop after the nickel plate, you can have a nice, durable finish but it will have a nickel cast, which has a silvery yellowish cast. This is where most of the appearance of chrome plating comes from....except the bluish cast. The chrome step will give it a bluish cast. Of course, the chrome finish will give more wear resistance and durability, too.

Often a flash copper is used first over steel, then an acid copper is sometimes used to provide build. Over brass, you can use acid copper for build if it is necessary without the flash copper. Remember that the copper step is usually needed if you are working towards a bright polished finish--or if you are working with metals such as pot metal that cannot tolerate the nickel plate directly applied. In this case flash copper is the only option. The reason for the copper: It is super easy to polish to a bright luster, and it can be sanded, soldered, and repaired easily for restoration purposes.

For your parts, I'm not sure you're looking for a dazzling brilliant finish. You're looking for a matte finish. The electroless process should work well for you. But it won't look exactly the same as a triple chrome finish. Either way, you shouldn't really need to copper plate your parts; I recall you said they were brass.

Ken