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Q&As since 1989


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Nickel Plating model railroad track

1996

Q. I am new to "plating" and I am interested in trying a little bit. What I have is an old 1953 model railroad in which the track is starting to pit and the like. All and All it is in pretty nice shape. I intend on trying to add a nickel plate on the existing material. I am going to try some sulfuric acid and nickel on a simple D Cell current source. So far am I on the right track?

Any advice would be appreciated.

Thanks in advance

Mike Alexander

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A. Hi, Mike.

For the purposes of understanding chemical principles such as Faraday's Law of Electrolysis and Avagadro's Number, hobbyists and students can easily do some minimal electroplating of pennies with zinc and dimes with copper as explained in our FAQ "How Plating Works", and we encourage you to try that -- you might find it fun.

But those experiments are for the purpose of understanding principles, not for real-world application because the plating will be too thin, poorly adherent (will easily rub off), dull (no brightness), porous (not corrosion resistant) -- in general, of no real-world value.

You can learn what is involved in functional nickel plating in good detail from this list of plating books hopefully available at a large library; perhaps the best of which is the ASM Metals Handbook Vol. 5.
-- because it explains concepts like the wetters, carriers, primary brighteners, buffers, etc., required for nickel electroplating.

Functional electroplating is pretty difficult. To start, you've got to get that track waterbreak-free clean in a near boiling mixture of caustic and detergent; then you need to remove the rust and tarnish with hydrochloric acid without eating away the track. However, for small lots where labor costs aren't an issue, in lieu of the chemical cleaning you can carefully scrub the items with a scrub brush [on eBay or Amazon] and powdered pumice [on eBay or Amazon] .

Then you may need to remove the plating that is on it with a nickel stripper, probably cyanide-based (not in my town, you don't) because you will not be able to get new plating to stick to the old passivated nickel plating. Then you'll go through a lot of "D" cells (the number can be calculated based on Faraday's Law) to plate just one piece of track and the plating will still be poor unless you used addition agents (the brightener, carrier, wetting agent), and can hold 140 degree temperature and supply good agitation and filtration.

If the old track is the same size as today's, you'll be better off buying replacement track. Due to the labor cost of onesy-twosy rework, replating will be far more expensive than new track, but a plating jobshop can do the restoration work for you if replacement track is unavailable.

Please try to get one of those plating books from the library if you are interested. Functional plating is interesting, but it is fairly complicated.

I'm not sure that the track is nickel plated though; I'd have suspected it to be tin plated. If you have decided to experiment you can buy an inexpensive tin-zinc plating kit from Eastwood, or there are outfits that serve hobby platers.

Good luck!

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey