Cord-Wound Staff Churn Drive: A Swinging Lever Twists the Dash To and Fro by Cords

"By taking hold of the handle of the lever, and moving it with a reciprocating motion, the cords attached to arc of the lever, will alternately wind and unwind on the pulley F, causing it to partially revolve in the direction of the lever, thus causing the cords E, E, to move the staff with a reciprocating motion."

Print the pulley (/uploads/blueprints/cord-wound-staff-churn-drive-pulley.stl), the lever head (/uploads/blueprints/cord-wound-staff-churn-drive-lever-arc.stl), the frame (/uploads/blueprints/cord-wound-staff-churn-drive-frame.stl) and the dash (/uploads/blueprints/cord-wound-staff-churn-drive-dash.stl). Print in PETG at 0.2 mm layers, 30 % infill, 4 walls; wash before first use.

Stand a pine post beside a tapered food-grade bucket. Clamp the frame on its top, with a pine arm out over the bucket's centre carrying the pulley on a 10 mm rod. Pin the lever head on a 10 mm rod lower in the frame and glue a 12 mm dowel handle into it.

Push the dash onto a 16 mm hardwood staff and stand it in the bucket, its top in the pulley's large groove. Tie a cord from each pulley groove, wind it a few turns round the staff, the two the same way, and fix it to a pin in the staff. Tie cord H round the pulley's small hub in opposite directions to the two ends of the lever's arc.

US 14,458 drawing sheet, public domain (expired patent).

Let the heavy cream stand until it reaches about 15 °C, checked with the thermometer. Pour in 3 litres. Swing the lever steadily to and fro; 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.

**Lucius Leavenworth** of Trumansburg, Tompkins County, New York, US 14,458, 18 March 1856. The lever's wrist pin could take "a connecting rod from a rocking chain or other power." He claimed the cords attached to the pulley and wound on the staff to give a rotary motion. A bucket, pine and printed parts stand in for his. FDM prints hold food in their layer lines, so wash well and replace when worn.