Ogee-Float Twin-Shaft Churn: Two Rocking Shafts Drive the Cream's Currents Into Each Other

"My invention consists first of two sets of beaters on two shafts so situated in an ovoid or elongated vessel that the beater on one shaft whirls all the cream in one end of the churn alternately forward and backward, while the beater on the other shaft whirls all the cream in the other end of the churn in the opposite direction, for the purpose of driving the currents of cream violently into each other at the central parts of the churn where the air is drawn into the cream."

Print four ogee floats, two arm hubs, the segment wheel with its handle and two pinions. Print in PETG at 0.2 mm layers, 30 % infill, 4 walls; wash before first use.

Stand a long rectangular food-grade container inside a larger one, spaced off by short pine cleats, so water can be poured between them. Stand two 10 mm square hardwood shafts in the inner one, 87 mm either side of the middle, each with a hub and a 10 mm square hardwood arm through it carrying a float at each end; set the two arms at right angles.

Fix a pine bar across the outer container, with bearing holes for the shafts and a pivot for the segment wheel between them. Fix a pinion on each shaft's top and mount the segment so it meshes both.

Let the heavy cream stand until it reaches about 15 °C, checked with the thermometer. Pour cold or lukewarm water into the space between the containers to set the temperature. Pour 2 litres of cream into the inner one and rock the handle steadily left and right; time until the butter comes. 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.

**Michael L. Bauder** of Elyria, Lorain County, Ohio, US 19,117, 19 January 1858. His inner body was zinc or tin; he wrote that the case could also serve as a refrigerator for packing butter, and that the churn is best worked with half the cover off. He did not claim shafts with beaters in round churns, nor a reciprocating motion; he claimed the elongated vessel with the two armed shafts in the case. Two containers and printed parts stand in for his. FDM prints hold food in their layer lines, so wash well and replace when worn.