Segment-Rack Zone Churn: A Lever Rocks the Dasher Shaft, a Toothed Tin Band Gathers the Butter at the Surface

"This zone is intended to be raised or lowered along the slide so as to accommodate itself to the quantity of cream in the churn—the upper edge being intended to rise to the surface of the cream or a little higher so that the radial proportions may gather the butter as it is formed."

Cut an 18 mm plywood disc 350 mm across for cover B, with a 17 mm hole in the middle and a 110 mm hole 106 mm off centre. Glue two 12 mm plywood rings under it, 292/264 mm and 350/312 mm across: the gap between them is the groove that takes the bucket's rim. Screw the two ears to the bucket's wall on opposite sides, hooks over the rim, and cut two 44 mm notches in the cover's edge and outer ring to pass them: drop the cover on and turn it 45 degrees to lock. Cut a 130 mm hatch D from 6 mm plywood with a dowel knob.

Screw the socket to the middle of the bucket's floor with an M4 screw and lock nut. Cut the stainless tube (16 mm) to 433 mm. Cut four hardwood arms 248 x 30 x 10 mm and three floats 216 x 40 x 8 mm; bore each 16.5 mm at its middle and the arms 8.4 mm at 118 mm each side. Fix the arms on the shaft 115, 140, 165 and 190 mm above its foot, all in line, and the floats 35, 60 and 85 mm up, each an eighth of a turn round more than the last and slanted 25 degrees, with M4 screws across. Push an 8 mm stainless rod 200 mm long through each end of the arms as the slides. Cut a tinplate strip 60 x 810 mm, roll it into a 253 mm band and screw the lap with M3 screws; screw ten tinplate tabs 26 x 50 mm inside it, evenly spaced. Clip it to the slides at the height the notebook gives.

Stand the shaft in its socket, lay the cover on and lock it. Fix the pinion on the shaft's top with an M4 screw across. Screw a hardwood upright I 44 x 30 mm, 162 mm tall, to the cover from below, its front face 38 mm behind the shaft's centre. Bolt the segment to it with an M12 bolt as pivot M so its teeth mesh with the pinion, and screw a hardwood lever G 340 x 30 x 14 mm on top of its socket.

Stand the bucket in a tub of ice water in warm weather or warm water in cold weather (ours, for his receptacle at the side) until the cream is about 15 °C. Pour in about 12 litres of heavy cream and set the zone's top edge at its surface. Lock the cover and rock the lever back and forth steadily; time it. Look through the hatch: the tabs gather the butter at the surface. When it has come, lift the cover and shaft out, pour off the buttermilk, wash the butter in cold water until it runs clear, work in a pinch of salt and weigh it.

**Charles W. Stafford** of Burlington, Iowa, US 22,093, 16 November 1858, "Churn". He preferred a tin body, light, cheap and quick to warm or cool, and claimed the general arrangement, the adjustable zone with its projections, the grooved cover with slots and ears, and the two covers. He gave no sizes. Every size and material is ours. His Fig. 4 draws S toothed on its face and N bevelled; ours is a crown-toothed segment with a straight pinion. His water receptacle hangs on the body's side; ours is a tub the bucket stands in.