Fan-Blown Jet Dasher Churn: A Fan on the Crank Shaft Blows Air Out Through the Dasher Below the Cream

"When motion is communicated to the driving shaft a current of air is thrown by the blower through the dasher shaft, and issues in fine jets from the shaft and wings of the dasher beneath the surface of the cream or milk in the churn."

Print the dasher (/uploads/blueprints/fan-blown-jet-dasher-churn-dasher.stl) standing, with supports, four corner plates (/uploads/blueprints/fan-blown-jet-dasher-churn-corner-plates.stl), the step (/uploads/blueprints/fan-blown-jet-dasher-churn-step.stl), the cover (/uploads/blueprints/fan-blown-jet-dasher-churn-cover.stl), two brackets (/uploads/blueprints/fan-blown-jet-dasher-churn-bracket.stl), the pinion (/uploads/blueprints/fan-blown-jet-dasher-churn-pinion.stl), the dasher-wheel (/uploads/blueprints/fan-blown-jet-dasher-churn-wheel-b.stl), the fan (/uploads/blueprints/fan-blown-jet-dasher-churn-fan.stl), its case (/uploads/blueprints/fan-blown-jet-dasher-churn-casing.stl), the duct (/uploads/blueprints/fan-blown-jet-dasher-churn-duct.stl) and the crank (/uploads/blueprints/fan-blown-jet-dasher-churn-crank.stl). The cover needs a 240 mm print bed. Print in PETG at 0.2 mm layers, 30 % infill, 4 walls; wash before first use.

Use a square container about 200 mm inside and at least 220 mm deep. Set the step in the middle of its floor and stand the dasher's pivot in it. Press a pair of corner plates into each corner, clear of the dasher's wings.

Lay the cover on with the dasher's top through its hole and slide the pinion onto the flat at the top. Screw the two brackets, the fan case and the duct's leg to the cover from below with M4 screws. Cut a 10 mm dowel 230 mm long and push it through the first bracket, the dasher-wheel, the second bracket, the case's bearing and the fan; press the wheel and fan tight, the wheel meshing the pinion. Push the case's outlet into the duct's socket and the duct's nozzle into the dasher's top. Fix the crank on the dowel's free end with an M3 screw drilled through it.

Pour in 3.5 litres of heavy cream at about 15 °C, checked with the thermometer, to above the wings' holes. Turn the crank steadily and time it with the stopwatch. When the butter comes, lift the cover and dasher out, pour off the buttermilk, wash the butter in cold water until it runs clear, work in a pinch of salt and weigh it.

**M. R. Marcell** of Dansville, Livingston County, New York, US 21,010, 27 July 1858. His fan case sat on the churn's cover round the driving shaft, its mouth entering the dasher shaft's top; he allowed the blower to stand at the side instead, geared to the driving shaft. His corner plates were metal. He claimed the dasher, with the blower, that sends air out in fine jets below the cream, and the double pierced corner plates in a churn box. Turned at crank speed, our small fan makes far less pressure than the cream's depth needs (step 1), so do not expect air from the jets; the dasher and the corner plates still work the cream. Our fan beside the dasher-wheel, the duct, the container, sizes and printed parts are ours. FDM prints hold food in their layer lines, so wash well and replace when worn.