Bulged-Rocker Separator Churn: Oblique Rockers and a Diagonal Comb

"The churn is then rocked from side to side producing a rapid and violent agitation of the cream toward the sides and ends of the box and through the separator, causing thereby a speedy transformation of the cream to butter: the separator serving to catch the particles of butter and assist in the gathering of the same."

Print the separator (/uploads/blueprints/bulged-rocker-separator-churn-separator.stl), two rockers (/uploads/blueprints/bulged-rocker-separator-churn-rocker.stl) and two bearings (/uploads/blueprints/bulged-rocker-separator-churn-bearing.stl). Print in PETG at 0.2 mm layers, 30 % infill, 4 walls; wash before first use.

Use a rectangular food-grade container about 220 by 140 mm. Seal the two bearings in opposite corners with food-safe silicone and stand the separator's legs in them along the diagonal.

Screw the two rockers under a pine board, parallel, running from alternate corners, with the swells on opposite sides, and stand the box on it. Push a 10 mm square hardwood shaft down through the lid into the separator and fix a thin hardwood lath on top as the springy handle.

US 14,677 drawing sheet, public domain (expired patent).

Let the heavy cream stand until it reaches about 15 °C, checked with the thermometer. Pour in 1 litre and close the lid. Rock the box from side to side by the handle; 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.

**William Newbrough** of Mohican, Ashland County, Ohio, US 14,677, 15 April 1856. He wrote that the rockers could go under any ordinary churn. He claimed the combination of the oblique bulged rockers with the diagonal separator. A container, pine and printed parts stand in for his box. FDM prints hold food in their layer lines, so wash well and replace when worn.