Shimpo Ball Mill Rack for Potters Wheel. Attaches to all wheels when used with a 12quot wheelhead except the M1. This spacesaving rack will allow you variable speed milling and grinding. The rack accommodates jars from 312quot to 9quot diameter up to 10quot long. Made of heavyduty cast iron, the unique folding design lets you use. Get A Quote. Ball Mills For Pottery .