I see CoilyGirls motor is thermally protected. Make sure any motor you use is thermally protected because we dont want to burn our house down. 1/4 HP is considered minimum for one roller, you need more hp for multi roller machines. The average "standard" rpm for motors is 1750, so you have to do some reduction with belts and pulleys to get your tube to go around 20 rpm. The math is tricky. You will want to shoot for 20 rpm on the tube with the ability to go slower for fragile or square pieces. Faster is ok for robust round pieces like mineral waters. Ball bearings are best, but plain sintered bronze bearings are okay if you keep them oiled. These are just basic rules of thumb. This thread is making me want to start building my machine. I am using a radical new design but I'm not sure how I'm going to pull it off yet. And, of course, the tubes and stopples and other stuff are a nightmare on their own. I want to use clear tubes but just look at the price of that crap. Go to McMaster-Carr.com and look up the prices on clear acrylic or polycarbonate tubes in the 5 6 7 8, 10" range. Ouch.