macsalab drive rolls for rod / ball mills are rubber coated and manufactured in double and triple roll models. the rolls are 120 mm diameter x 1200 mm long and powered by a 0.37 kw 220 volt motor with a variable speed controller. ball/rod mill literature
it's not always true that roll refiners and ball mills are mutually exclusive: i know of one italian equipment manufacturer that offers a "turnkey" system that includes a roaster, cracker/winnower, roll refiner used a liquor grinder , and a ball mill.
make your own ball mill stand section: glazes, subsection: general the rods are far enough apart so that the shoulder of the jar runs low enough to contact the caster wheels. wine making carbuoys are good also since they are very straight cylinders that will roll without hopping in the stand.
four inexpensive fixed caster wheels were mounted on top of the platform for the drum to roll on. they were mounted about 2 inches in from the edges of the platform, and 7.5 inches apart. the ball mill is powered by a fairly robust 12v dc motor salvaged from a junked printer. it had a pulley for a fine-toothed belt on it.
this is a great way to roll firework stars fast and easy. it took 14 mins to make a couple hundred 5/16" stars. see the next video for finished stars. rolling firework stars part 1 of 3 ball