Spiral-Flange Perforated Dasher Churn: Curved Holed Dashers Fling the Cream Out, a Spiral Flange With Vanes Drives It Back Down

"Around the dasher staff is wound a spiral flange, E, upon which are formed auxiliary dashers, a, a. These dashers are not perforated but catch the cream as it approaches the shaft with an upward tendency and throw it back toward the bottom of the churn box or toward the large or main dashers below them."

Use a 20-litre food-grade bucket as the box A. Cut a 12 mm HDPE lid to its top, 304 mm across, bored 16.6 mm at the centre as the staff's top bearing.

Turn a hardwood staff B 32 mm across and 315 mm long. Set a 10 mm stainless pin 10 mm out of its foot and a 16 mm stainless rod 133 mm long 20 mm into its top. Slide the two flange sections on, one 80 to 120 mm above the foot and one 190 to 230 mm, the upper turned a quarter turn on from the lower, and fix each with a screw through its sleeve. Bore the staff 10.2 mm across at 45, 155 and 265 mm above its foot, each a quarter turn from the last, and push a 10 mm stainless rod 120 mm long through each. Slide a dasher D on each end, curves leading the same way round, and fix it with a split pin. Pin a crank of mild steel flat bar, 108 mm throw, with a hardwood handle on the stainless top.

Set the step on the bucket's floor, stand the dasher in it, pour in about 12 litres of heavy cream at about 15 °C, checked with the thermometer, and put on the lid over the staff's top. Turn the crank steadily, the dashers' curved ends leading, timing it. When the butter comes, lift the lid and dasher out, take out the butter, pour the buttermilk into a bowl, wash the butter in cold water until it runs clear, salt and weigh it.

**John J. Watson** of Buffalo, Erie County, New York, US 30,438, 16 October 1860, "Churn-Dasher". He claimed "the arrangement of the main dashers, D, D, with the auxiliary dashers, a a and the spiral flange E". He gives the dashers' form only as drawn, and does not say how many there are or how far round the flange runs; Fig. 1 draws one twisted band up the staff's height, while ours is two short sections between the dashers' levels. His dashers were metal; ours are printed. Every size here is ours.