Typical Grinder Installations. PROSCO Inc. Rubber Roller Grinders are Custom Designed for a Perfect Fit on Your Lathe. Dry Or Wet Operation. Front Or Rear Mounted. Up To 7000 Rpms (With Ac Drive) Custom & Specialty Grinders. Straight And Tapered Shafts. 3hp, 5hp, 7.5hp, 10hp, 12hp, 15hp, 20hp, 25hp; 230v, 380v, 480v, 600v.