Sliding-Bar Air-Tube Dasher Churn: Churn Low, Then Raise the Bar and Turn Back to Gather

"After the butter is produced, the bar D is raised to the surface, or nearly to the surface, of the cream and is supported in proper position by the pin (h) which is inserted in the shaft B below the collar (g). By turning the shaft B, gently in a reverse direction the butter will be collected, the inclined boards (i) forming chambers to receive it."

Print the dasher bar with its inclined boards (/uploads/blueprints/sliding-bar-air-tube-dasher-churn-dasher-bar.stl), the collar (/uploads/blueprints/sliding-bar-air-tube-dasher-churn-collar.stl), the step (/uploads/blueprints/sliding-bar-air-tube-dasher-churn-step.stl), the crown wheel (/uploads/blueprints/sliding-bar-air-tube-dasher-churn-crown-wheel.stl), the pinion (/uploads/blueprints/sliding-bar-air-tube-dasher-churn-pinion.stl) and the standard (/uploads/blueprints/sliding-bar-air-tube-dasher-churn-standard.stl). Print in PETG at 0.2 mm layers, 30 % infill, 4 walls; wash before first use.

Glue an 8 mm food-grade tube into each socket so its top stands above the cream, slightly inclined. Slide the bar onto a 10 mm square hardwood shaft standing in the step in a round food-grade container. Hang the bar from the collar by four 3 mm stainless rods, and drill the shaft for a pin under the collar at the churning and the gathering heights.

Fix half the lid with a hole for the shaft, the pinion on its top and the standard with the crown wheel meshing it; screw a dowel handle into the wheel.

Let the heavy cream stand until it reaches about 15 °C, checked with the thermometer. Pour in 2 litres. With the bar low, crank steadily; time until the butter comes. Raise the bar to the surface, pin the collar there, and crank gently the other way to gather the butter. 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 H. Truesdell** of Elgin, Kane County, Illinois, US 18,936, 22 December 1857. He did not claim bringing air into the cream, nor adjusting dashers broadly; he claimed the bar and its inclined boards that let air in turning one way and form chambers to gather the butter turning the other. Printed parts and a container stand in for his. FDM prints hold food in their layer lines, so wash well and replace when worn.