Sure I could but I hate putting ebay links cause in one month from now someone searches the thread and they can't tell what's going on cause the link's no good. I'd rather just dole out the terms so you can plug them into ebay or whatever yourself.
In short, if you are going to motorize a grain mill, there are tons of options. Most people do a 1725 RPM motor (cause it's a usual suspect and thus not as pricey) and reduce the speed down (and thereby the torque up) by way of a pulley system/wheel. I don't want that many moving parts, so your other option is to get a gearmotor. This has a speed reducing gear in it. It's pretty hard to find the right amount of torque and speed when you go this route though (and by that I'm speaking of used on ebay or from 'surplus' wholesalers on the the net (like
www.surpluscenter.com... search for gearmotor). But they come in various mounting scenarios like 'right angle'. For me, I have not seen a 'right angle gearmotor' that I can mount pointing up (which would make it a similar profile to the mill and hopper). So, I'm getting a gear reducer gearbox which is basically what the gearmotor has built in but it's separate. It'll probably end up heavier and bigger than doing it all in one, but for my mounting situation, I need the orientation as described ... mostly because motors at that power level tend to be more than 10 inches long (and won't fit my table). The gear reducers say both what the max torque they can support is (in horsepower) and the speed redux (like 10:1).
So, in that most people think that around 200 RPM is best, then go for a 1725 RPM motor and a 10:1 reducer which reduces the speed down to 175 RPM. And then make sure it's the horse power you need (1/3 +, I would say) which will translate into torque above 50 lb/in.
Some come with capacitor start and some don't. I'm not really sure much about what that means and all, but why not then just get a 1/2 hp or better motor and not need it in the first place.
Also, the more power these have, the more used ones you'll find that are 3 phase 220V and not 115V. So, bargain hunting is a challenge. Craigslist is good for it though. Also, there are AC and DC ones so choose carefully.
One other thing that I'm just learning about now is the mounting options for the gearbox and motor. There are different sizes, so you have to be careful. I think the typical size is called '56C', but I'm in need of educating myself further before I lay down the plastic.
And, after you have your mill and motor setup, you'll have to get a 'lovejoy' coupler which basically takes whichever size shaft on your motor and converts it to whichever size shaft on your mill (so they can be different). And it also helps correct for mounting irregularities.
Just do a search for 'motorize monster mill' and you'll get a couple good links.
P.S.. One neat little bit of info regarding mills that have a 1/2" shaft upgrade option like a Monster Mill is that the 1/2" shaft is better for the pulley system cause it inhibits bending of the axle. It's not necessary for gearmotors though since bending isn't presented. Maybe something you should think about re: the Barley Crusher w/ 3/8" shaft and go for a gearmotor rather than a pulley. I'm not really sure why the are so much more prevalent than gearmotors other than cost. The gear reducing mechanism is another cost ($60+ ish).
