Rocking Twin-Dasher Lever Churn: One Lever Rocks the Box and Works Two Dashers Through a Perforated Wall

"The machine is operated by moving the upright lever l, to and fro, which rocks the box, while at the same time it works the dashers up and down, thus throwing the cream through the partition d, till the butter is made."

Print the partition (/uploads/blueprints/rocking-twin-dasher-lever-churn-partition.stl), two dashers (/uploads/blueprints/rocking-twin-dasher-lever-churn-dasher.stl), two dasher arms (/uploads/blueprints/rocking-twin-dasher-lever-churn-dasher-arm.stl) and two lower arms (/uploads/blueprints/rocking-twin-dasher-lever-churn-lower-arm.stl). Print in PETG at 0.2 mm layers, 30 % infill, 4 walls; wash before first use.

Build a pine box about 260 × 120 × 150 mm with a close-fitting lid, sealed inside. Glue the partition across its middle and screw two curved pine rockers lengthwise underneath. Drill the lid for the two dasher handles.

Set a 10 mm square shaft across each end on two studs, 60 mm above the lid. Fit a dasher arm on each, pointing inward and pinned to its dasher's handle, and a lower arm on each outside the box. Join the lower arms with a pine bar, and pivot an upright pine lever on a block near the box's foot, pinned to the bar's middle.

US 3,764 drawing sheet, public domain (expired patent).

Let the heavy cream stand until it reaches about 15 °C, checked with the thermometer. Pour in 1.5 litres. Work the lever to and fro: the box rocks and the dashers rise and fall in turn. Keep fingers clear of the arms and the rockers. 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.

**A. C. Stiles** of South Bloomfield, Pickaway County, Ohio, US 3,764, 27 September 1844. He claimed the combination of the rockers and dashers in the double-chambered churn. His drawing gives no sizes; ours are ours. FDM prints hold food in their layer lines, so wash well and replace when worn.