Rotary-Tub Spout Churn: A Friction Wheel Spins the Tub, a Fixed Spout Catches the Climbing Cream and Jets It Into a Basket

"A quantity of cream being placed in the tub F, and the latter rapidly rotated by means of the crank D and friction wheel E, the cream ascends the sides of the tub by centrifugal force until arrested by the flange f and being caught by the spout K is deflected inward and projected in a forcible and continuous stream into the basket H, causing violent agitation in the body of cream as well as friction as it flows out through the apertures in the basket."

Make a hardwood base 520 x 560 mm. Screw a hardwood standard 60 mm square in its middle, its top bored 16.6 mm to take a 16 mm stainless spindle. Cut a plywood disk plate 300 mm across, fix the spindle in its centre, and screw the bucket down on it, sealing the screw heads inside with silicone. Screw a ring of HDPE sheet, 26 mm wide, inside the bucket 340 mm up as the flange f, and a hardwood socket bored 12.6 mm in the floor's centre.

Turn a hardwood wheel E 220 mm across with its rim rounded in section, as the patent's "regular convexity". Bolt two hardwood bearing blocks to the base so a 16 mm stainless shaft C runs straight out from under the spindle, at a height where the wheel, fixed on its inner end 50 mm from the spindle, just carries the plate. The shaft must point at the spindle, so the wheel rolls on the plate without scrubbing. Fix the wheel on the shaft, and a hardwood crank D with a dowel handle on its end; hold it with collars.

Stand two hardwood standards J 30 x 30 mm either side of the bucket and join their tops with a bar I across it, bored 12.6 mm over the centre. Drop a 12 mm stainless pin through the bar into the floor socket and slide the basket onto it so it turns freely. Clip the spout's clamp on the bar so its mouth sits just under the flange, close to the wall, facing against the tub's turn; slide it in or out to suit.

Pour about 5 litres of heavy cream at about 15 °C, checked with the thermometer, into the tub around the basket. Turn the crank briskly, timing it, until the cream climbs to the flange and runs from the spout into the basket. Keep on until the butter has gathered in the basket. Lift out the pin and basket with the butter, pour off the buttermilk into a bowl, wash the butter in cold water until it runs clear, salt and weigh it.

**Clark Wright** and **William Phelps** of Sycamore, DeKalb County, Illinois, US 28,802, 19 June 1860, "Churn". They claimed the rotary tub, stationary spout and basket together. Their wheel and plate meet as two crossed discs, the wheel's rounded rim avoiding both side thrust and broad rubbing faces. Every size here is ours.