Modern manufacturing
Bell Aircraft's assembly plant in Wheatfield, New York in 1944
Electrification of factories, which had begun gradually in the 1890s after the introduction of the practical DC motor and the AC motor, was fastest between 1900 and 1930. This was aided by the establishment of electric utilities with central stations and the lowering of electricity prices from 1914 to 1917. Electric motors allowed more flexibility in manufacturing and required less maintenance than line shafts and belts. Many factories witnessed a 30% increase in output owing to the increasing shift to electric motors. Electrification enabled modern mass production, and the biggest impact of early mass production was in the manufacturing of everyday items, such as at the Ball Brothers Glass Manufacturing Company, which electrified its mason jar plant in Muncie, Indiana, U.S. around 1900. The new automated process used glass blowing machines to replace 210 craftsman glass blowers and helpers. A small electric truck was now used to handle 150 dozen bottles at a time whereas previously used hand trucks could only carry 6 dozen bottles at a time. Electric mixers replaced men with shovels handling sand and other ingredients that were fed into the glass furnace. An electric overhead crane replaced 36 day laborers for moving heavy loads across the factory.[35]
Mass production was popularized in the late 1910s and 1920s by Henry Ford's Ford Motor Company, which introduced electric motors to the then-well-known technique of chain or sequential production. Ford also bought or designed and built special purpose machine tools and fixtures such as multiple spindle drill presses that could drill every hole on one side of an engine block in one operation and a multiple head milling machine that could simultaneously machine 15 engine blocks held on a single fixture. All of these machine tools were arranged systematically in the production flow and some had special carriages for rolling heavy items into machining positions. Production of the Ford Model T used 32,000 machine tools.
Lean manufacturing, also known as just-in-time manufacturing, was developed in Japan in the 1930s. It is a production method aimed primarily at reducing times within the production system as well as response times from suppliers and to customers. It was introduced in Australia in the 1950s by the British Motor Corporation (Australia) at its Victoria Park plant in Sydney, from where the idea later migrated to Toyota. News spread to western countries from Japan in 1977 in two English-language articles: one referred to the methodology as the "Ohno system", after Taiichi Ohno, who was instrumental in its development within Toyota. The other article, by Toyota authors in an international journal, provided additional details. Finally, those and other publicity were translated into implementations, beginning in 1980 and then quickly multiplying throughout the industry in the United States and other countries.