Hay! I want to do the same thing, only I'm about 3 years from being ready to build mine. I don't think they ever rotary dumped 2 bay hopper cars. To old. Your best chouces are the Aristo 100 ton hopper or the USA Trains 3 bay hopper. American Mainline wants to manufacture G scale Bethgon Coalporters but that project is on hold. I would suggest building it ot handle just one type of car. If you build it for one type of car, buy one, that way you have a car to test it with. And let me know how it goes. I may just have Eaglewings Ironcraft build one for me.
I am starting a rotary car dumper for a G scale layout I want to build. Can anyone give me sizes on open hoppers fro different scales. I don't know what scale to make it. The layout will be early 1980's so cars that are older 2 and 3 pocket coal hoppers are what I have in mind. I have full scale plans but don't know what the best cars are. The dumper will be working some what like the dumper at a power plant here in Ohio. The walthers HO moded is close.I know a little about G and have been selling of my HO to help fund getting G equipment.
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