Nested Hollow-Dasher Churn: Two Dasher Frames Turn Contrary Ways, Their Hollowed Side Pieces Driving Cream at Webs

"The cream is projected by the surfaces of the hollow s, c, onto the wall of the vessel, by which it is constrained to take up a circular motion till obstructed by the webs, a, and reflected by them in currents, toward the middle of the vessel, and with a velocity increasing as the distances between these hollows and webs diminish."

Screw four hardwood webs 4 mm thick and 10 deep upright inside the bucket a quarter turn apart, from the floor to 310 mm up, sealing the screw holes outside with silicone. Screw a hardwood block 50 x 50 x 8 mm to the floor's centre as the step r and bore it 12.6 mm, 6 deep. Cut a 12 mm stainless rod 60 mm long as the pivot bolt e.

Halve together two hardwood arms 30 x 30 mm, 240 long, for the top and two for the bottom, crossed. Cut four side pieces 20 x 42 mm, 295 long, and join the arms' ends top and bottom with them, 310 mm overall. Hollow each side piece's outer edge on the same side, 12 mm deep at the middle and running out near the ends. Glue a hardwood web b, 4 x 11 mm, along each side piece's inner face. Bore the lower arms' crossing 12.6 mm for the pivot bolt and the upper arms' crossing 33 mm for the journal; fix an 18 mm stainless tube 102 mm long upright over the upper crossing as the hollow arbor.

Make the inner dasher the same way from 25 mm hardwood: arms 164 mm long, four side pieces 18 x 34 mm, 195 overall, hollowed 10 mm deep on the opposite edge from the outer dasher's, no webs. Bore the lower arms' crossing 13 mm, 12 deep, for the pivot bolt. Turn a hardwood journal G 32 mm across and 55 tall with two lugs, cut a 12.4 mm square socket in its top, and screw it to the upper arms' crossing.

Set the inner dasher inside the outer, its journal up through the outer's upper arms, and stand both on the pivot bolt in the step. Cut a hardwood cover in two halves, 350 x 330 x 15 mm overall, with a 24 mm hole for the arbor; slide pinion F onto the arbor above it. File the bottom 40 mm of a 12 mm stainless shaft square to fit the journal's socket, pass it down through the arbor, and key pinion E on its top. On one half of the cover screw two hardwood standards carrying a 12 mm shaft H with wheel D meshing E above and F below, a hardwood winch I with a dowel handle, and a bracket over E holding the shaft's top.

Pour about 8 litres of heavy cream at about 15 °C, checked with the thermometer, into the bucket, set the dashers and the gearing in place, and turn the winch steadily, timing it, the way that brings each frame's hollows toward the webs ahead of them. When the butter comes, lift off the cover and gearing, lift out the dashers, take out the butter, pour the buttermilk into a bowl, wash the butter in cold water until it runs clear, salt and weigh it.

**Stephen P. Dunham** and **Austin Hipple** of Kilbourne, Delaware County, Ohio, US 27,894, 17 April 1860, "Churn". They did not claim a wheel geared with two pinions to turn dashers contrary ways, but the hollowed side pieces working with the webs on the vessel and on the outer dasher. Their vessel is conical, wider at the bottom; ours is a bucket. Every size here is ours, and our gears are printed.