I need a knowledgeable input to this question about the levels of conductivity that the various rail types (brass, steel & nickel silver) have to offer I have run both brass & nickel silver rails during my years in model railroading but no steel. I recall that brass rail was a real pain to use unless you cleaned it regularly to remove any oxides. I seem to recall reading that the oxide on nickel silver was a better conductor than the oxide free rail itself. I have no experience with steel. So what’s the skinny? Was/is the nickel silver oxide a better conductor than clean rail or not? Is steel better than nickel or brass? Inquiring minds want to know. Thanx.
I would stick with the NS track. It’s the best.
Brass was a pain and steel can rust.
No oxidation is the best of course. I would go to the right “search our communtiy” and type in keywood “gleam” for the general forum to get several threads on the GLeam method of highly polishing the rails to help avoid oxidation on the rails and allow for better conductivity on NS track.
Nickel Silver is generally regarded as the “best choice” insofar as the rail to use. Brass is regarded as… well… recycling material.
Nickle Silver is recognized as the best bet. Not as conductive as the other 2 but as the OP noted the oxide is actually a better conductor than clean rail. It’s still better to keep the rail clean though. The oxide can attract dust and dirt.
Steel rail has the best conductivity.
Nickel silver is the best for use on a model railroad.
In order of conductivity (1st is best conductor):
brass (great conductor)
steel (good conductor)
nickel silver (fair conductor)
oxidized nickel silver (poor conductor)
oxidized steel (aka rust) (non-conductor)
oxidized brass (non-conductor)
In addition to having an oxide that conducts a little, nickel silver is far more resistant to oxidation in the 1st place.
The conductivity differences between the metals is not important - controlling the oxidation is what controls the conductivity. Oxidation occurs much faster in humid environments, and in polluted/dirty air (lots of suspended chemicals to speed the reaction).
Preventing/removing oxidation can be done several ways:
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Removal of oxidation (and dirt) by chemicals or scraping. Track cleaners and Bright Boys do this. But these do nothing to slow re-oxidation.
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Coating metal with a really thin layer of CRC 2-26, clipper oil, No-Ox, metal wax, or similar. The good coatings prevent oxygen in the air from reaching the base metal so easily while allowing wheel pressure to conduct electricity. Paint is a good coating to isolate metal from the air, but will not allow wheel pressure to conduct. Oxidation must be removed prior to coating for the coating to have the desired effect.
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Burnishing and hardening the surface of the metal. This is done by running trains with metal wheels and/or “gleaming”. The heavier the train, and the more frequently they are run, the less oxidation you will have. The oxide can’t stand up to the pressure and polishing action of the metal wheels, and disintegrates. The polishing action of the wheels smooths and hardens the surface of the rail - which is why prototype rail is shiny on top where the trains run
Just want to add that with a sufficient number and spacing of feeders, relative conductivity of the rail is a very minor issue. Not noticeable at all. I feed around every six feet. More at special work. Every track section has either a feeder or soldered joiners to another section with a feeder.
NS is by far the metal of choice for the reasons stated in previous posts.
Karl
Silver;
Copper; and
Gold.
If you encounter any silver or gold track in your travels buy up all you can get; its suppose to be a hedge against inflation!
Of the three materials listed above only copper is practical for model railroad track–although there apparently was some industrialist in Italy awhile back who had a couple of hundred feet of gold track drawn; both brass and nickel silver are copper alloys. Brass is a slightly better conductor but it’s oxidation is not conductive while nickel silver oxidation pretty much retains it’s conductivity.
Why, Brother Poteet, I am frequently ask, don’t we use pure copper for track? Well, technically pure copper is a better conductor than brass but it corrodes considerable faster and it’s oxide is even less-conductive than oxidized brass; besides that it is really not very malleable . . . . . and remember, our rail needs to be bendable!