Nested Counter-Dasher Pin-Clutch Churn: Two Dashers Turn Opposite Ways, Reverse the Winch and Only the Outer One Gathers

"Thus, I am enabled to produce two different movements of the dashers; one for churning, and the other for gathering the butter, by simply turning the winch in opposite directions."

Print the inner dasher, the outer dasher, the hollow journal, pinions G and H, the driving wheel, the disk, the pin, the step, the cover, the standard and the crank. Print in PETG at 0.2 mm layers, 30 % infill, 4 walls; wash before first use.

Cut a 10 mm square hardwood strip about 330 mm long as the shaft and sand it. Set the step in the bottom of the pot. Push the shaft through the inner dasher, stand it in the step, and lower the outer dasher round it, its bottom piece turning freely on the shaft. Push the hollow journal onto the outer dasher's top piece, over the shaft.

Lay the cover on the pot with the journal through its centre. Slide pinion G onto the flat at the journal's top. Slide pinion H loose onto the shaft above it, put the pin in its hole, and fit the disk on the shaft over it, notch down. Screw the standard to the cover from below with two M4 screws, push a 10 mm dowel through it as the winch axle, press the driving wheel tight onto its inner end so it meshes with G below and H above, and fix the crank on its outer end with an M3 screw drilled through the dowel.

Pour in 1 litre of heavy cream at about 15 °C, checked with the thermometer. Turn the winch the way that couples the pin, so both dashers turn opposite to each other, and time it with the stopwatch. When the butter comes, turn the winch the other way: the pin rides up its slope, the inner dasher stands still and the outer one gathers the butter at the edge. Pour off the buttermilk, wash the butter in cold water until it runs clear, work in a pinch of salt and weigh it.

**T. B. Harper** of Xenia, Greene County, Ohio, US 20,062, 27 April 1858, signed 6 March 1858. Each of his dashers had top and bottom pieces joined at their ends by vertical wings, bevelled to cleave the cream one way on one dasher and the other way on the other. He claimed the pinion H, the disk L and the pin h, arranged with the winch and the two dashers as described. Our sizes, gear counts and printed parts are ours. FDM prints hold food in their layer lines, so wash well and replace when worn.