Re: Rail

I worked on the Atlanta Zoo train for two years or so from 1991-1993.
Our track was 16" gauge with two Minature Trains F-7's. At the time, the smallest rail available was 10# and it was alleged to have been discontinued about the time the zoo ousted the external vendor and bought a 24" gauge train. We used 12-14# rail as I recall. (some 10# was used on the one spur we used for loco and car repair)
If you have an application for your trolley that is a business, I'd recommend at least 10-12# rail.
The head of the Zoo train (a fellow live steamer in 7.5" gauge) said that 8# and 10# had become hard to find because the mills quit rolling it due to low demand.
The zoo train had had problems with 8# rail kinking in the sun. Also, there were wear problems in the 50' curve by the petting zoo's pig pen. (The 50' radius curve also had a 3.25% grade on the 90 degree turn - it is interesting to see the 24" gauge loco try the turn - it does make it with alot of flange squeals).