Why, oh why, do my rails go black?

[John R Smith]

 

I expect that you, like me, have got used to the ritual of cleaning the track before each operating session. It's not too dreadful a task these days, as I no longer have a very extensive layout, but it is still a bit of a pain. I had always accepted the published wisdom that the black scum which builds up on the rails (and the wheels too, eventually) was to do with electricity and tiny sparks arcing away between the wheels and track, producing a sort of carbon deposit.

 

So when I began my coarse scale O gauge project I was looking forward to the end of these domestic chores and track cleaning woes. Why? Because electricity, volts, amps and watts are banished forever from my new layout, which is powered entirely by clockwork (or Spring Drive, as Jack Ray would have preferred). Therefore, with no arcing between rail and wheel there should be no carbon deposits, right?

 

Imagine then my horror when I found that my rails got just as black, just as quickly, as on my fine-scale electric setup. I can scrub all the track sparkling clean with IPA, wire-brush the wheels, and within a few days the the black scum returns. So this is obviously nothing to do with electricity at all, but if not, what is the cause?

 

For your reference- my rails are brass, and the wheels are a mix of mazak (wagons and locos), cast iron (coaching stock) and a bit of steel (a few wagons).

 

I seem to have been cleaning track for almost as long as I can remember. The only layout where I never used to bother was my dear old Horby Dublo 6x4, where it appeared to be self-cleaning, somehow. There's a lot to be said for centre third . . .

J

 

[APOLLO]

Brass tends to tarnish quickly, where are your tracks located, ? A damp(ish) cold shed etc would worsen the tarnishing.

 

Nickel silver, though expensive, is far better than brass or steel.

 

Brit15

[goldfish]

If you are using the track purely for clockwork is there actually any need to clean it? Other than for purley cosmetic purposes.

The usual source of dirt from clockwork is oil, it doesn't matter how careful you are to keep it away from the wheels it still gets on the rails.

[Nearholmer]

Yep, clockwork flings oil about in all directions, and brass tarnishes to brownish-black simply by contact with air.

 

This has been outside enjoying the vagaries of the weather for upwards of fifteen years, so has a nice patina now.

 

 

Different brasses give slightly different colours of brownish-black.

 

Nickel silver also tarnishes, and in some conditions it will do so in a much more troublesome way than brass, but indoors in low humidity it behaves itself.

Edited April 23 by Nearholmer

[John R Smith]

2 hours ago, goldfish said:

If you are using the track purely for clockwork is there actually any need to clean it? Other than for purley cosmetic purposes.

 

A very good point. The reason I might bother to clean the track at all is simply that it would seem the black goo builds up on the wheels, and after a time (months? years?) forms a horrible lumpy crust on the wheel tyres. I know this, because with every vintage B-L wagon I obtain, I have to spend a happy half hour or so chipping the hardened goo away with a screwdriver blade and then finishing the job off with a wire brush.

 

1 hour ago, Nearholmer said:

brass tarnishes to brownish-black simply by contact with air.

 

True, but my problem is not tarnish. A control section of B-L track left out but with no stock running on it stays clean. It might be tarnished, but no black goo wipes off with IPA and a cotton bud.

 

It sounds as if oil is at the root of this problem. I must admit, I do tend to be generous with the lube on my clockwork mechs . . .

[goldfish]

10 minutes ago, John R Smith said:

It sounds as if oil is at the root of this problem. I must admit, I do tend to be generous with the lube on my clockwork mechs . . .

 

Its all those cogs whirling around, they need to be lubricated but they fling oil everywhere.