Fast-and-Loose Bucket Churn: One Way the Buckets Cross to Churn, the Other They Close to Gather

"The loose bucket working by its nut on the left hand screw on the spindle brings the end of the said bucket tightly against the other as they get into line."

Print the fast bucket (/uploads/blueprints/fast-and-loose-bucket-churn-fast-bucket.stl), the loose bucket with its nut slot (/uploads/blueprints/fast-and-loose-bucket-churn-loose-bucket.stl) and two bushings (/uploads/blueprints/fast-and-loose-bucket-churn-bushing.stl). Print in PETG at 0.2 mm layers, 30 % infill, 4 walls; wash before first use.

Press an M10 nut into each end trap of the fast bucket and screw it onto an M10 stainless threaded rod near one end, locked. Drop an M10 nut into the loose bucket's slot and screw it on beside the fast one. Fit a short pin in the fast bucket's hole so the loose bucket's lug can turn only a quarter turn.

Lay a round food-grade container about 180 mm across on its side in a pine cradle and cut a lid opening in its top. Seal a bushing in each end on the axis, pass the rod through, and fit a pine crank arm and handle with nuts.

Let the heavy cream stand until it reaches about 15 °C, checked with the thermometer. Pour in 1.5 litres. Turn the crank the way that opens the loose bucket across the fast one; time until the butter comes. Turn it back so the buckets close in line and roll the butter together. Pour off the buttermilk, add cold water, churn a little and pour off again until it runs clear; work in a pinch of salt and weigh the butter.

**Franklin Thorpe** of Shelbyville, Shelby County, Illinois, US 15,787, 23 September 1856. He claimed the fast and loose buckets, the loose one slackened and tightened by "the screw upon the spindle; or equivalent devices." His screw was left-handed; a common right-hand M10 rod simply swaps which way of the crank churns and which gathers. A container, a threaded rod and printed parts stand in for his tub and spindle. FDM prints hold food in their layer lines, so wash well and replace when worn.