Gidday Harold, while not knocking any of the other methods, I’m a big fan of the “John Allen” track cleaning car. Here are two of my home made ones.
I live in an active geothermal area were hydrogen sulphide can play havoc with electrical appliances, Doesn’t do “her in doors” silver tea set much good either. A new modeller to the club was given brass track which he has just had to replace with nickel silver. Like Randy suggests I have a policy of running one in every train.
Hope you get your problem sorted,
Cheers, the Bear.