Slatted-Wing Concave-Hub Churn: Flanged Wings Lift the Butter, a Hollow-Sided Hub Rolls It Up

"As fast as the butter is produced the flanges collect and retain it upon the slatted wings until the wings arise out of the cream and assume a position which compels it to fall into the concaves of the solid hub."

Print the hub standing on end, four wings flat with the flange up, two end caps, the crank and the collar. Print in PETG at 0.2 mm layers, 30 % infill, 4 walls; wash before first use.

Use a container at least 230 mm long, 180 mm wide and 200 mm deep inside. Drill a 10.5 mm hole in the middle of each end wall, 100 mm above the inside floor. Cut a 10 mm dowel 310 mm long as the axle and sand it.

Slide the four wings into the hub's slots, every flange facing the same way round. Screw an end cap on each end with four M3 screws. Push the axle through one end wall, the hub and the other wall. Drill 2.5 mm through the axle at the hub's cross hole and fix it with an M3 screw; fit the crank on one end and the collar on the other the same way.

Pour in 2 litres of heavy cream at about 15 °C, checked with the thermometer. Turn the crank so the flanges lead, and time it with the stopwatch. Keep turning once the butter comes: the flanges lift it out of the cream and drop it into the hub's concaves, where it gathers into a roll. Lift the dasher out, pour off the buttermilk, wash the butter in cold water until it runs clear, work in a pinch of salt and weigh it.

**William Brown** of Duncannon, Perry County, Pennsylvania, US 20,189, 11 May 1858, signed 13 April 1858. He hung the dasher in the churn box "in the usual manner" and claimed the slatted wings, the flanges and the solid concaved hub in combination. He wrote that slats parallel with the hub would do in a measure, but set them at right angles so the butter rolls to the centre with less obstruction. Our container, sizes, dovetails and printed parts are ours. FDM prints hold food in their layer lines, so wash well and replace when worn.