In the 1920s, almost all electric arc welding was done with large, expensive, three-phase motor generators with DC output. Because three-phase primary wall power was usually only available in big cities, most blacksmiths in rural areas were still using the ancient hammer and forge technique to weld metal.
In 1929, Niels Miller recognized the need for a small, affordable arc welder that would operate on the type of electricity readily available in rural Wisconsin. With no money for raw materials, he used scrap sheet metal, core and coil materials to hammer together that first welder in his basement. His simple, non-rotating AC welder was smaller, lighter and less expensive than the DC units currently available.
Noteworthy Inventions of the 1920s
1920: The hair dryer. Previously, woman dried their hair by inserting a hose in the exhaust of a vacuum cleaner.
1923: By adding scraping blades to Benjamin Holt’s “caterpillar” crawling tractor, the LaPlant-Choate Manufacturing Company produced the first bulldozer in 1923.
1927: Edwin Perkins of Omaha, Nebraska created Kool-Aid. The original flavors were Cherry, Lemon-Lime, Grape, Orange, Root Beer, Strawberry and Raspberry.
1928: Otto Frederick Rowedder of Iowa introduced the world’s first mechanical bread slicer and Charles Strite's spring-loaded, automatic, pop-up toaster finally became a commercial success.