Ball Mills vs Rod Mills - 911 MetallurgistJul 3, 2017 . When the mill is rotated without feed or with very fine feed, the rods are in parallel alignment and in contact with one another for their full length. New feed entering at one end of the mill causes the rod charge to spread at that end. This produces a series of wedge shaped slots tapering toward the discharge.cara kerja ball mill rod mill,Laboratory Ball Mill Plans - Homemade Ball Mill / Rod Mill DrawingSep 26, 2017 . By this drawing, it is suggested that a typical homemade laboratory rod mill or ball mill might be fabricated from 20 cm (8 inch) diameter schedule 40 type 316 stainless steel pipe and would be about 38 cm (15 inches) long. The plans show stainless steel grinding rods for this size of mill may be a graduated.