from another forum.
My youngest has a (more or less HO) TOMY set that runs off AA batteries and produces 'smoke' using water. It smokes quite well, enough to be clearly obvious although not like some really copious smokers I've seen.
Since the batteries last at least a week of heavy use and they drive the motor as well as the smoke producing unit, I cannot for the life of me understand why someone hasn't done this with O gauge unless its protected nine ways to Sunday by patents.
The water is administered with an eye dropper and the smoke is produced for a surprising length of time. It doesnt make the engine wet either so I cant see it being a nuisance with our rails or a danger with the electricity.
I keep meaning to buy another and dissect it to see if it can be transplanted.
