Spiral-Scraper Ice-Cream Freezer: Turn One Way to Spin the Can, the Other to Scrape It Clean

"d, is a lifting catch which prevents the revolution of the cream holder when it is desired to revolve the movable arm E, in the direction shown by the arrow in Fig. 4, by which motion the frozen cream is scraped off the inner sides of the cream holder G, and forced to the bottom of the same by means of the spiral scraper D, thereby causing the unfrozen cream to rise to the top, which in turn will be perfectly mixed and equally frozen."

Print the spiral scraper, the socket, the lid with its cross bar, the arm and the catch. Print in PETG at 0.2 mm layers, 30 % infill, 4 walls; wash before first use.

Glue the socket to the floor of a clean tin can about 98 mm across. Round off the foot of a 10 mm square hardwood shaft so it turns in the socket, slide the scraper on, stand it in the can and push the lid on.

Stand the can on a block in a bucket. Clamp a pine beam across the rim with the shaft up through its hole. Fix the arm on the shaft just above the cross bar with a screw, and hang the catch on its pin so it locks on the bar when you crank anticlockwise, seen from above. Drop a dowel peg through the beam beside the bar as the lifting catch, and glue on a pine crank.

Fill the can a third full with cream sweetened with sugar. Pack crushed ice and salt, three parts to one, round it. With the peg up, crank anticlockwise: the can turns in the ice. Every few minutes drop the peg and crank clockwise a few turns: the can stays and the spiral scrapes the wall and drives the frozen cream down. Repeat until it is thick.

**Joseph Parisette** of Indianapolis, Indiana, US 15,083, 10 June 1856. His ice tub was hard wood, shaped like a churn, with a cock near the bottom to draw off the melt water and a hoop and lock piece holding the cover to the holder. He claimed the spiral scraper with the drop catches, regulating the can and scraper. Our sizes, the left-hand spiral and the tin can are ours. FDM prints hold food in their layer lines, so wash well and replace when worn.