Brass steam locomotive driver plating.

[WReid]

I have a couple of Van Hobbies ( Samhongsa ) CNR brass steam locomotives I an repairing and repainting. One has light wear on the drivers and the other has heavy wear. I could replace the drivers with new ones but I am thinking of replating the original ones. I have used one of the small silver replating kits before with excellent results.

The only thing I need to know is if the plating on the drivers is nickel plating. I have read that some people replate the drivers with silver. I have always been under the impression that they were nickel plated not silver plated. I do not feel like buying a nickel plating kit and fine out the drivers are silver or chrome plated. Most of all since I have read nickel cannot be applied over silver or chrome ( silver will not go over chrome also ). Now silver can be applied over nickel plating I have been told.wall1

Now I am almost willing to bet the factory plating is nickel but thought I would ask and see if anyone can confirm this. Thanks.


Wayne Reid
Ontario,Canada

 

[nachoman]

most drivers i am familiar with were either brass, or nickle-silver. Nickle silver is actually neither nickle or silver; it is actually a different alloy of brass. I havent heard of drivers being made of much else, with the possible exception of steel on limited models. I suppose the brass could have been plated with something to reduce oxidation...but i wouldn't use silver because it tarnishes worse than brass.

Kevin

 

[nkp174]

most drivers i am familiar with were either brass, or nickle-silver. Nickle silver is actually neither nickle or silver; it is actually a different alloy of brass. I havent heard of drivers being made of much else, with the possible exception of steel on limited models. I suppose the brass could have been plated with something to reduce oxidation...but i wouldn't use silver because it tarnishes worse than brass.

Kevin

:agree1:

Brass has the best electrical pickup (when clean) and steel has the worst.
Steel has the best adhesion and brass has the worst. Nickel Silver is in between in both categories...but doesn't have the corrosion problems that plague brass.

I'd bet they're Nickel Silver Plated...presuming their HO. If they are O...they could be steel.

 

[doctorwayne]

Another option could be to install pick-up shoes. I added a pair to this old John English Pacific, now in the shop for rebuilding. The original brass drivers never were plated, so the pick-up shoes solved a problem that I had put up with since the '50s. Mine are from Tomar - you get enough in one pack to do several locos.

Once the arm portion is painted, they're not too visible, as seen on this installation on an Athearn switcher:

If you're using DCC, and have isolated the motor from the frame, mount the shoes using the nylon screws from Kadee, and use a plastic spacer between the shoe and the bottom cover plate - the lid from a Kadee coupler box should work well.

Wayne

 

[pgandw]

Nickel plating is the norm over brass tires to get rid of the brass color, and that's what was done at the factory.

Brass tires have better adhesion and conductivity, but aren't the right color, and are much more easily oxidized. The latter prevents conductivity until the oxidation is worn away or cleaned off.

Chrome plating would be an interesting experiment. The extra hardness should improve adhesion significantly, and the change in conductivity really doesn't matter much as long as the oxidation is kept at bay. This assumes the chrome plating can be as thin and even as nickel plating.

Silver oxidizes easily, and I don't see any upsides not shared by nickel or chrome.

Custom locomotive builders prefer to put steel or stainless steel tires on their models' drivers when the client will accept it. The steel has significantly better adhesion than brass or nickel silver. The downside is making sure the tires don't rust when the model is stored.

my thoughts, your choices

 

[WReid]

Thanks to all who have replied. I am know 99.9% sure the plating is nickel. Several owners of Van Hobbies HO scale brass steam have contacted me and all have said they are sure it is nickel. I also used tried a testing kit for silver ( acid based kit ) and the plating is not silver. Also due to the fact it is not as bright and shiny as chrome nickel seems to be once again the correct choice.

Doctorwayne I like the info you posted on wiper pickups. I never thought about using them. A very good idea as I am planning on adding sound to my two N-5-d locomotives and extra pickups will be a must.

My biggest concern about the worn plating was having the brass tire wear due to lack of plating. I have a few drivers here from another brass locomotive where the tires are worn bad and have groves starting to show. Seeing as proper replacement drivers can be hard to find I would like to save the ones off the N-5-d's. I have ordered a nickel plating kit and expect it here in a week or so. Once I have the chance to try it out I will post some pictures and the results.

I am also considering ordering a chrome plating kit and testing it on some spare junk drivers. But first I have to see if it will go over the original nickel plating as well as the brass.

One thing I did notice the other day on one of the used spare Van Hobbies driver sets I got with the one locomotive is that the cast white metal center of the driver seems to be breaking down. It is a bit crumbly and seems to have lost some strength. I have read about this issue a few times before. Good news is it a a very worn driver set with a busted side rod crankpin hole and not one off the locomotives. It may be a good thing I have purchased a couple of sets of 63 inch drivers from Greenway Products. Their drivers have cast brass centers. The ones I purchased are very close in looks to the original Van Hobbies drivers on my N-5-d's. Actually the driver set with the heavy counterweight looks much closer to the heavy weighted driver on the real N-5-d's in photos I have the the Van Hobbies driver.


Wayne Reid
Ontario,Canada