Spring-Lever Dasher Churn: A Hand Lever and a Faster Bar on a Post Drive the Old Dasher Down, a Rubber Spring Lifts It

"The labor of lifting and returning the ordinary churn dasher by the smooth vertical handle, is by my process, or that which my improvement introduces, changed to an easy downward pressure upon a nearly horizontal bar or handle, the parts returning upwardly to their place by the force of the spring which was easily overcome by the downward pressure."

Screw a hardwood base 520 x 400 mm and stand the bucket on it, held by a few cleats round its foot, as the patent says. Cut an HDPE cover with a 28 mm hole in the middle. Make a dasher of two crossed hardwood boards 220 x 40 x 16 mm on a 25 mm hardwood handle long enough to stand 300 mm above the cover.

Glue up a hardwood standard 60 x 40 mm, 800 tall, and frame it into the base behind the churn, 210 mm from its centre. Rout a slot a 18 mm wide through it from 480 to 700 mm up, and bore 10.4 mm holes b across it every 30 mm. Make a hardwood block c that slides in the slot with shoulders bearing on both faces, with a 10 mm stainless pin through a hole b to set its height, and a tail behind the standard for the spring k.

Cut a hardwood lever F 28 x 16 mm, 810 long, and a piece g 340 long. Pivot both on a 10 mm stainless pin through a hole b 620 mm up, F on one face of the standard and g on the other, 110 mm of each behind it, and join them there with a pin j. At the churn's centre join them with a hardwood block i with a 28 mm upright hole for the dasher handle. Cut a hardwood bar d 24 x 16 mm, pivot it on the block c 55 mm from its back end, and join its back end to the pin j with two mild steel flat bar links f, 71 mm between holes. Join d's front end, 170 mm out, to the dasher handle with a flat bar link e 80 mm long hanging down to a pin m through the handle; bore the hole m where the dasher rests on the bottom with the levers level.

Loop a length of elastic cord round the pin j and tie both ends to the block c's tail, tight enough to lift the lever and dasher when let go: the spring k. Tie a shorter loop from the bar d to the lever F as the spring l.

Pour about 8 litres of heavy cream at about 15 °C, checked with the thermometer, into the churn and put on the cover. Set the block c so a full press of the handle brings the dasher near the bottom and the spring lifts it clear of the cream. Press the handle down and let it rise, steadily, timing it. When the butter comes, unpin the link e, lift out the dasher, take out the butter, pour the buttermilk into a bowl, wash the butter in cold water until it runs clear, salt and weigh it.

**N. B. Cooper** of Gratis, Preble County, Ohio, US 28,970, 3 July 1860, "Churn". He claimed the mechanism of base, upright, block, hand lever, pivoted bar, links and springs together, to make the old dasher churn lighter work, likening it to a pump on a "spring pole". His springs are india rubber; ours are elastic cord. Every size here is ours.