At Ford, cars came off the moving line at three-minute intervals, or six feet per minute; this increased production eight to one. 12.5 man-hours became 1 hour 33 minutes; it was so successful that paint became a bottleneck. The moving line cut costs; a Model T cost around $825 in 1908 and around $575 by 1912. In 1914 an assembly line worker could buy one with four months' pay. After the pay increase, Ford claimed that its turnover rate of 31.9 percent in 1913 decreased to 1.4 percent in 1915. Ford offered nearly three times the wages paid at other unskilled manufacturing plants. The Highland Park complex included offices, factories, a power plant and a foundry; that was part of Ford's strategy of integrating the supply chain. At about 102 acres it was the largest manufacturing facility in the world when it opened.
More than 15 million Model Ts were made. They reached 9,000 to 10,000 cars a day in 1925, or 2 million a year; the price was just $260; the Volkswagen Beetle passed the Model T's total production in 1972. Electrification of factories began around 1900. At first big motors drove long line shafts. Once small motors were available, factories switched to a motor at each machine. Getting rid of line shafts freed factory layout to be more efficient. Arkwright's achievement was to combine power, machinery, semi-skilled labor and the new raw material of cotton to create mass-produced yarn. His organizational skills earned him the title father of the modern industrial factory system. The Toyota Production System has roots in the automatic loom invented by Sakichi Toyoda; it grew from the Just-in-Time concept developed by Kiichiro Toyoda. Sakichi wanted to make things easier for his mother, who worked late into the night on a manual loom.
With jidoka, when a machine problem, a quality problem or a work delay occurs, the machine can stop automatically. Or the operator can stop the line by pulling the stop cord; this keeps defective products from flowing on and builds quality into the process. At Toyota, when equipment stops, the andon, a problem display board, lights up to notify workers. People need only respond when there is an abnormality. No one has to watch over the equipment. In Toyota's just-in-time loop, each step keeps a small store of finished parts; the next step picks up what it needs. Then it quickly refills the store. Only what is needed is made. In the late 1940s Toyota started studying supermarkets; the idea was to apply shelf-stocking techniques to the factory floor. In a supermarket, customers retrieve what they need at the required time; the store stocks only what it expects to sell.
Some historians have determined that Eli Whitney never actually achieved interchangeable-parts manufacturing, even though others once credited him with it. His guns were costly and handmade by skilled workmen. Lean is a way of thinking about creating needed value with fewer resources and less waste; it is also a practice of continuous experimentation to achieve perfect value with zero waste. Lean thinking and practice occur together.
Words to know
- jidoka: stop-on-error
- andon: signal board
- bottleneck: slow step
- electrification: adding electric power
