Pin-Cylinder Box Churn: A Cylinder of Square Pins Turns Through a Row of Pins in the Lid, Then Washes the Butter in the Churn

"So when the lid is shut the pins in the cylinder will revolve through between the pins that are in the lid, and break or churn the milk or cream; and when all the milk is let off by a faucet, and a pail of water thrown into the churn, by turning the crank eight or ten times around the pins in the cylinder will press and wash the butter through the pins in the lid."

Glue up two hardwood ends 22 mm thick, 350 mm wide and 400 mm tall. On each draw the inside: a 300 mm half circle, its centre 250 mm up, with straight sides rising 150 mm above the centre to the top. Rout a groove 1.6 mm wide and 8 mm deep on that line, and cut the bottom edge into feet. Bend a 1.5 mm stainless sheet 516 mm long into a U to fit the line, set its edges into both grooves with silicone sealant, and screw hardwood sides 22 mm thick outside its straight parts. Join the ends through the top corners, inside, with two M8 threaded rods, nuts and washers outside: the patent's iron rods with screws and burrs.

Turn a hardwood cylinder 76 mm across and 488 mm long (the patent's "about three inches"). Mark six places 80 mm apart, the outer ones 44 mm from the ends, and at each chop four square mortises 25 mm across and 25 deep, a quarter turn apart. Cut 24 hardwood pins 25 mm square ("about one inch") and 127 mm long, point their ends, and glue them in so their points stand 140 mm from the axis, each pinned with a small dowel. Bore a 30 mm hole 40 deep in the crank end for the square boxing and a 10.2 mm hole 20 deep in the other end for the centre rod.

Glue the square boxing into the cylinder's crank end. Bore the crank end 40 mm at the axis, 150 mm above the half circle's bottom, and seal the cone boxing into it, its wide end outward. Cut a 16 mm stainless rod 139 mm long for the gudgeon and file 38 mm of its inner end square, 12 mm across the flats (the patent's square end is 1.5 inch long). Pin the printed cone on it where it seats in the boxing, slide on a shaft collar as the shoulder, and pin a crank of mild steel flat bar, 120 mm throw, with a hardwood handle, on its outer end. Bend a spring steel strip into a U with a slot for the gudgeon and screw its legs to the end so it presses the collar inward. Bore the other end 10.2 mm at the axis and push a 10 mm stainless rod 51 mm long ("about two inches" by "three-eighths") through into the cylinder.

Bore the other end 24 mm through at the bottom, its lower edge just above the sheet, and seal the printed faucet into it with its outlet down. Turn a hardwood pin 19 mm across and 170 mm long with a knob, cut two grooves near its point and fit two O-rings as the patent's rubber packing, so pushed in it closes the tube and drawn back past the outlet it lets the milk run off.

Cut a hardwood lid 544 x 350 x 22 mm and hang it on two butt hinges along the back. Cut five hardwood pins 25 mm square, set them in mortises in the lid on its centre line, midway between the cylinder's pin places, reaching 105 mm down with pointed ends, so they stop 7 mm off the cylinder. Cut five strips of stainless strip 12 mm wide, file fine teeth along one edge, and screw one along a corner of each lid pin so the teeth stand about 3 mm ("about an eighth of an inch") proud. Fit two stainless tubes 38 mm long ("about an inch and a half") through the lid near its ends as air tubes.

Pour about 15 litres of heavy cream at about 15 °C, checked with the thermometer, into the box, shut the lid and turn the crank steadily, timing it. When the butter comes, draw the faucet's pin and let the buttermilk run into a bowl. Shut it, throw in a pail of cold water, and turn the crank eight or ten times so the pins press and wash the butter through the lid pins; let the water off and repeat until it runs clear. Sprinkle in the salt and turn a few times to work it through. To take the cylinder out, draw the gudgeon back against its spring and the centre rod back. Lift out the butter and weigh it.

**John Park** of Joliet, Will County, Illinois, US 29,397, 31 July 1860, "Churn", a churn and butter-dresser. He claimed the rows of pins in the cylinder and lid "for churning, and dressing the butter ready for use while in the churn", the faucet, the cone gudgeon, the spring, the tin strips for catching hairs and the air tubes. His text describes the gudgeon, boxings and spring from a Fig. 3 that is not on the drawing sheet, and some of its letters do not match the two figures; the gudgeon parts here follow the text, in our own form. His strips were tin, his faucet and boxings zinc; ours are stainless and printed. The sizes in quotes are his; all others are ours.