Spring-Float Barrel Churn: Floats Stand Rigid to Churn, Fold Back on Springs to Gather and Work

"When the disks and floats are turned the other way so as to gather and amass the butter by pressing it against the sides of the barrel, the springs allow the floats to yield or give way, when they come over and strike on the buttermilk and butter and assume a tangential direction."

Print two disks (/uploads/blueprints/spring-float-barrel-churn-disk.stl) and two floats (/uploads/blueprints/spring-float-barrel-churn-float.stl). Print in PETG at 0.2 mm layers, 30 % infill, 4 walls; wash before first use.

Fix the two disks on a 10 mm square hardwood shaft and join them with two 4 mm stainless rods. Pivot each float between the disks on a 4 mm rod, and hook a spring from its eye to the anchor hole in a disk so it presses the float against its stop.

Lay a round food-grade container about 170 mm across on its side in a pine cradle, cut a door in its top with a cork vent, and run the shaft through its ends on the axis with a crank outside.

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 holds the floats on their stops; time until the butter comes. Turn it back so the floats fold and press the butter against the barrel; draw off the buttermilk, add salt and work the crank a little back and forth to mix it in, as he did. Weigh the butter.

**Benjamin Beers** of New Fairfield, Fairfield County, Connecticut, US 18,797, 8 December 1857. He bent a wooden hoop into the barrel's body between two heads, cheaper than staves and less likely to leak. He claimed the rotating dasher with spring floats to churn and to work the butter. A container and printed parts stand in for his barrel. FDM prints hold food in their layer lines, so wash well and replace when worn.