I built mine back in 1994 or '95 and finally got around to building a dedicated cabinet for it last year to help contain the dust from milling. The mill is mahogany and white oak body with white oak roller support slider for gap adjustment. Mahogany plywood hopper. 2" x 8" hardened tool steel rollers powered by a 200rpm gear motor. The torque on the motor is unreal. I'd like a bigger hopper, but it mills as fast as I can pour the grain in, so it's not that big of a deal for me.
Here's V2.0 of my former Valley Mill. Paint and wiring in the switch comes tomorrow.
I heated the bottle neck up and narrowed it up in the vice and made it twice as wide. Not brewing till next weekend, so we'll see how it goes then.
The last hopper wasn't steep enough and didn't distribute the grain along the roller very good.
Bodine gearmotor off e-bay, DC, converted to AC. A lovejoy and a right-angle attachment for a power drill - sits on the bucket, goes anywhere, doesn't take up much space. The rpm is low, torque is high, bet it would crush rocks.
the DC to AC converter box I built (with a little help from an electronics forum)