When free-flowing powders are being filled, a method of cutting off the powder supply is required. Usually, the best method of achieving this objective is to use a "spinner disc" as shown alongside. Attached to the protruding auger end is a spinner disc, a saucer shaped disc designed to retain the product flow. All powders have an angle of repose, the angle at which a collapsing heap of powder will come to rest rather than continue to spread outwards: the angle (top enclosed angle) for small smooth spherical beads would be much greater than, for instance, granulated sugar. The distance between the bottom of the funnel and the spinner disc is determined by the powder dosing rate, i.e.; the gap needed to permit unrestricted product flow. The spinner disc is sized to prevent the powder trickling over the rim of the disc once the auger has stopped, taking into account this gap and the powder's angle of repose. As the spinner disc throws the powder outwards, a simple collection cone funnels it down to an appropriate size. The spinner disc approach achieves a perfectly clean fill without expensive shut-off valves and complicated pneumatic/moving parts.

The size of the auger and funnel is determined by a number of factors: fill weight, dosing rate, accuracy and container neck opening. The smaller the auger/funnel, the slower the dosing rate but greater the accuracy. Conversely, a larger auger delivers more quickly but less accurately. Where a wide range of fill weights are required, more than one auger/funnel set may be required to achieve the required combination of speed and accuracy. As a rule of thumb, a ratio of 5:1 for each set may be considered appropriate. Accordingly, if a range of weights from 10g to 1 kilo+ was required, three tooling sets would probably suffice; one small set for weights of 10g to 50g, a second for 50g to 250g and a large set for 250g to 1.25 kilo.

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