Optimum choice of the make-up ball sizes for maximum throughput .3 shows the typical variation of the S values with particle size xi for different ball diameters. For the same amount of ball charge, the number of balls in the mill decreases as the ball size increases. Thus, the S values are lower for larger balls. However, larger balls are capable of breaking large particles; therefore, the size at.typical size of ball miller,Ball Mills - 911 MetallurgistDrum-scoop feeder made of welded steel, is available. Specify size desired. When ordering, include a small sketch of your ball mill classifier layout. Right hand mill is standard. This should show the ball mill (feed, discharge and position of drive); Unit Flotation Cell.