Ball Mills vs Rod Mills - 911 MetallurgistJul 3, 2017 . Thus, quantitatively, less material can progress through the voids in the rod mill grinding media than in the ball mill, and the path of the material is more confined. . Selective and non-selective grinding are used here to compare products that have the same amount of the subsieve size. Then the product.ball mill and ball mill difference,Ball Mills vs Rod Mills | AM King Industries, IncBall mills & rod mills are both excellent mining machines. Know the important differences between ball mills & rod mills when selecting used grinding equipment.