I like cordless drill and screw driver motors.
Come with planetary gears that often get you right into
your target RPM range.
Come in various sizes and can handle wheeled platforms
up to about 100 pounds.
And not very expensive for what you get. Just don't buy the really
cheap Black & Decker stuff as they don't have anything worth
working with inside.
One downside is that you usually need to make custom mounts
and sometimes other special mods.
Not a problem if you have access to a decent shop but can be
a knock out factor if all you have is a saw and a drill press.
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