Counter-Turning Cylinder Churn: The Ribbed Cylinder Turns One Way While the Dashers Inside Turn the Other

"Now it will readily be seen that whenever rotation is given to the shaft that it and the dashers will traverse in one direction and that the cylinder and slats will traverse in a contrary direction, and that the velocity of the one in relation to that of the other will depend upon the number of teeth and comparative diameter of the pinions and the toothed surface on the head of the cylinder."

Cut two hardwood heads 364 mm across from 25 mm board, each with a hub 50 mm across bored 17 mm on the axis, the geared head's hub 38 mm long. Bend 1.5 mm stainless sheet into a shell 360 mm across inside and 450 long, screw it to the heads with silicone sealant, and screw four hardwood ribs 30 x 30 mm, 450 long, inside it a quarter turn apart. Cut a door 140 x 160 mm in the shell, hung on two small hinges and closed with a hook. Screw the printed toothed ring to the geared head's face.

Cut a 16 mm stainless shaft 662 mm long. Screw four hardwood dashers 430 x 122 x 16 mm to hardwood blocks pinned on it, a quarter turn apart, reaching 140 mm from the axis, and pass it through the heads' hubs. Fit the crown wheel on the geared end and a crank 160 mm long with a handle beyond it.

On a base board stand a post with a hardwood bearing block bored 51 mm for the plain head's hub. At the geared end stand a hardwood standard m, and fix a 12 mm stainless rod l upright in its top, running up into a second bearing block for the geared hub just outside the toothed ring. On l, below the shaft, slide the two pinions joined by a short stainless tube: the upper one meshing the crown wheel j, the lower the toothed ring o. Hold them with collars.

Turn the door uppermost, pour in about 12 litres of heavy cream at about 15 °C, checked with the thermometer, and close it. Turn the crank steadily, timing it: the patent says three to five minutes. When the butter comes, turn the door down over a bowl, let the buttermilk run out, take out the butter, wash it in cold water until it runs clear, salt and weigh it.

**Edwin Ward** of New York, US 27,175, 14 February 1860, "Churn". He claimed the horizontal cylinder with ribs and an interior shaft with dashers, made to turn in opposite directions. His bevel pinions and the toothed surface on the head are here printed crown gears and pinions, and his fixed shaft l is upright, carrying the geared end's bearing. The patent gives no sizes; every size here is ours.