At the tractor shows, and threshing bees I attend, there is usually someone processing corn. They arrive with a pickup load of ear corn, husk the ears, then run them through a hand cranked corn sheller. Then take the shelled corn, fan it, and run it through a small grinder which cracks it. Sometimes they tighten down the burrs in the grinder, or have a second one set up. The corn meal coming out of this second run is good enough to make corn bread from. These are usually cast iron, and attached to a board, they aren't much bigger than a toaster. Some of them have hand cranks, and some are run from the hit and miss engine by flatbelt. I know mills used stones to grind with, but smaller setups usually used a burr grinder. Just my thoughts.