Round-Bottom Square Churn: A Geared Dasher Turns in a Vessel Round Up to Its Blades and Square Above, Breakers From the Lid

"The shape of the dasher-blades and their inclined position to the bottom when revolving is such as to give a lifting and revolving motion to the cream, while the shape of the cream-vessel further assists in lessening the time usually required to churn, for the cream when driven by the dasher against the breakers E and c and from side to side and corner to corner of the cream-vessel is very greatly agitated."

Glue up a square hardwood box 260 x 260 mm inside and 300 deep from 20 mm boards with a 20 mm bottom. Seal the four corner fillets into the corners with food-safe silicone so the lower 110 mm is round, the skirt round the floor's edge, the step at the centre of the floor and the rib c on one side of the round part. Seal every joint. Screw a hardwood lug a 60 x 25 mm to two opposite sides near the top to lift it.

Cut a 12 mm stainless dasher shaft 360 mm long with a pin turned on its foot to fit the step. Fix the four blades on a printed or hardwood hub 25 to 45 mm above its foot, a quarter turn apart, each sloping 30 degrees. Cut a 12 mm HDPE lid B to the box's outside in two halves; hinge one half to the box and leave the other loose, with hooks and eyes b to fasten them. Screw two hardwood breakers E 12 x 80 mm, 140 long, under the lid 70 mm either side of the centre, reaching down to 160 mm above the floor. Bore the lid 14 mm at the centre for the shaft. Screw two hardwood bearing blocks 50 x 25 x 118 mm on the fixed half, bored 16.6 mm across 93 mm up; pin the pinion on the shaft 40 mm above the lid, and run a 16 mm stainless shaft 150 mm long through the blocks with the wheel C pinned on meshing it, a shaft collar, and a crank of mild steel flat bar, 100 mm throw, with a hardwood handle.

Set the dasher in its step, pour about 9 litres of heavy cream at about 15 °C, checked with the thermometer, into the vessel so it stands a little above the round part, close the loose half of the lid and hook it. Turn the crank steadily, timing it. When the butter comes, lift the loose half, take out the dasher by lifting the fixed half on its hinges, take out the butter, pour the buttermilk into a bowl, wash the butter in cold water until it runs clear, salt and weigh it.

**Thomas R. Markillie** of Winchester, Scott County, Illinois, US 33,154, 27 August 1861, "Improvement in Churns". He claimed "the cream-vessel constructed round at the bottom as high up as the height of the dashers, with the rest of the body of the vessel square, and this in combination with the revolving dasher". He made the vessel of earthenware, finding it the easiest to clean and keep sweet; ours keeps his shape in a sealed hardwood box with printed fillets, which must be scalded and dried with care; his vessel narrows toward the bottom, ours has straight sides. His gearing was a bevel wheel and pinion; ours is a printed crown wheel and pinion. The patent gives no sizes; every size here is ours.