The assembly line was a system through which items were mass-produced in a flow.

Mass Production

Predecessors to mass production

Mass production begins at Ford

The assembly line

The spread and limits of mass production

Mass production and advertising

Supporters and detractors of mass production

Mass production today

Resources

Mass production is a system of manufacturing products that uses specialized labor, machinery, the smooth and logical flow of materials, and an assembly line to turn out large volumes of the same product at the lowest possible cost. The fullest expression of mass production was probably found at the Ford Motor Company in the early years of the twentieth century, when hundreds of thousands of Model Ts were produced a year, all exactly the same.

Predecessors to mass production

The principals of mass production grew out of manufacturing techniques that were already widespread in the United States. Called “the American system” or the “uniformity system,” these techniques called for goods made of interchangeable parts. This meant that the cost of parts went down, but it was expensive to set up an interchangeable parts system.

Initially the uniformity system was most important in the manufacture of military equipment and clocks, both of which were built from many small parts that had to be made carefully. The United States government wanted to build weapons of high quality cheaply and swiftly, and make the parts uniform so that they could be quickly repaired during a battle. The process began at the end of the 1700s. At that time, while two rifles might look the same, any given part from one probably would not fit into the other. Guns were instead made one at a time by skilled craftsmen.

Guns required parts to be made with great accuracy. The federal government financed the initial attempts to use interchangeable parts. Eli Whitney, the inventor of the cotton gin, began the task around 1798. The parts of his muskets became more standardized but they were not really interchangeable. New equipment was invented that made parts with greater precision, and a system was created to ensure interchangeability. Patterns were used to make the parts, and a series of standardized tools were then used to measure them. Inspectors were sent to different arms factories. As a result, by mid-century the parts made at one factory fit into a gun made at another. Previously, the parts made by one worker would not fit into a gun made by the person next to him.

Around 1800, clocks still were made one at a time, by hand. As a result, they were so expensive that few people owned one. The demand for clocks increased as more people lived in cities and had tight work

schedules. To make clocks more cheaply, manufacturers began using power machinery and dividing labor so that workers specialized in a few tasks. Patterns were used to make parts interchangeable. Using these techniques, over 80,000 wooden clocks were made in Connecticut in 1836—twice as many as were owned in all of the United States in 1800. Division of labor was further refined so that by the 1850s, 60 workers had a part in making each clock. At the same time, fewer skilled workers were required because more work was done by machine, and this saved money. The price of a clock dropped from $10 in 1800, to $1.50 about 60 years later.

The techniques used to manufacture clocks and guns spread to other industries. The industrial revolution was underway and an increasing number of products were in demand by business and individuals. The uniformity system was used in varying degrees to make sewing machines, bicycles, and mechanized farm equipment. In each case, some fitting had to be done by specialists. No one had looked at the process as a whole and broken it down into small tasks arranged in the most efficient order possible.

Such ideas were in the air, however. In the 1880s and 1890s management theorist Frederick W. Taylor studied the motion of people at work. He believed that production could be made more efficient by seeing where time and motion were wasted, then designing better work methods.

Mass production begins at Ford

The various threads of mass production came together at the Ford Motor Co. in Highland Park, Michigan, from 1908 to 1915. Cars were a relatively new invention and were still too expensive for the average person. Many were too heavy or low powered to be practical. Henry Ford set out to produce a light, strong car that could be sold at a reasonable price. His Model T, released in 1908, was designed to meet these goals. Ford’s top engineers and mechanics had backgrounds in the uniformity system, making sewing machines and farm equipment. From the beginning, they adopted interchangeability of parts as a core idea.

After studying how to make cars in the simplest most logical, way possible, Ford built a Model T factory between 1908 and 1910 that favored the sequential assembly of parts. Machine tools, which made the parts of the car, were designed to perform one specialized operation. One machine tool did nothing but drill 45 holes into the side of an engine block. The machine tools were placed at the point in the assembly sequence where they were used; previous manufacturers usually had grouped machine tools together by category.

By 1913, a finished Model T rolled out of the factory every 40 seconds. Production went from 14,000 in 1909 to 189,000 in 1913, while the price dropped from $950 to $550. Contemporary observers were amazed by this level of productivity, but a final innovation was coming.

The assembly line

Initially groups of workers at Ford moved down a line of parts and subassemblies, each carrying out a specific task. But some workers and groups were faster or slower than others, and they often got in each other’s way. So Ford and his technicians decided to move the work instead of the workers. If engines in need of assembly were moved by a conveyor belt, the speed of work would become standardized to the speed the conveyor belt moved.

The concept of the assembly line came from many places, including slaughterhouses, where they operated in reverse. An animal carcass, hung on a hook, would slide down an overhead rail, while different workers removed various cuts of meat. No one had applied this idea to manufacturing, however.

After months of experimenting with various lengths and rates of speed for the assembly line, Ford switched its factory to assembly line production in 1913. The amount of time required to build a car plummeted to about a third of what it had been, and production skyrocketed, reaching 585,000 in 1916. Because the assembly line was so demanding on workers, many left. To avoid constantly hiring and training new workers, Ford began paying them $5 a day—double the average wages at the time.

The spread and limits of mass production

Ford became the toast of the nation. Manufacturers of many types quickly became interested in his methods. The company’s manufacturing process was initially known as Fordism, before being called mass production in the 1920s. Soon other car manufacturers, as well as manufacturers ranging from household appliances to radios, were using variations on Ford’s methods. Ford’s system called for making one unchanging product. Each copy of a product was exactly the same, and customers didn’t have any choices about the cars they wanted to buy. For the first 12 years of its production, the Model T was available only in black. However, by the time the 15 millionth Model T had been built in 1927, the basic design was 20 years old and the market was saturated. No one wanted to buy any more Model Ts and its sales were falling fast.

When one of Ford’s rivals, General Motors, designed and expanded its own mass production system during the 1920s, it built it with a greater amount of flexibility. GM used general purpose machine tools that could be adapted quickly to design changes. It also built the parts that went into its cars at a variety of locations, rather than all in the same factory as at Ford. When GM switched from a four-cylinder engine to a six-cylinder engine, the company first perfected the equipment at a small experimental plant. It was then able to switch over the main engine plant in Flint, Michigan, to six-cylinder production in a mere three weeks. Other parts of GM’s business continued with no interruption at all.

In contrast, when Ford switched from the dying Model T to the Model A in 1927, the entire factory had to be shut down for six months. Ford had become so good at producing one product, and had become so specialized, that the change to a new product threw the company into chaos. After this demonstration of the shortcomings of doing everything in one factory, Ford too became less centralized. Mass production clearly had needed more flexibility; now it had it.

Mass production and advertising

Mass production requires mass consumption. Thus mass production helped create the modern advertising industry as manufacturers sought to make consumers buy their products. But what if everyone already had bought a car? Partly to give customers more choices, partly to give those who already owned a car a reason to buy another, in the 1920s GM began creating a new version of its cars each year. In the 1930s, Ford followed. While mass-production purists like Henry Ford felt this was a marketing gimmick more appropriate for clothes than cars, most consumers were happy to finally have more choice in what they bought. Further, the Model T had been designed purely to function well. Many found it ugly. The Model A was considered far more visually appealing. Industrial design became important in winning customers. Just because hundreds of thousands of copies of a product were made did not mean they had to be visually uninteresting.

Supporters and detractors of mass production

As the idea of mass production became popular, manufacturers and industrialists of every kind looked for new areas in which to apply its methods. Henry Ford tried with mixed success to grow and process soybeans using mass production methods, turning them into products ranging from food to plastics and fabrics. Foster Gunnison considered himself the “Henry Ford of housing” because he built prefabricated houses on an assembly line beginning in the 1930s. Many furniture makers also tried mass production methods, but they did not work well for houses or furniture. Tastes for these kind of commodities were highly personal, and once bought, they were held onto for a long time. Henry Ford and others believed that mass production would save the world and move into every facet of life, but it became clear that it was not suitable for building everything.

Many people were suspicious of mass production. It arose at a time when workers were leaving small towns and farms to work in the more anonymous environment of the big city. Many saw mass production as a reflection of this loss of individuality. Some critics saw it as a cause as well. In a mass production economy, everyone bought products that were exactly the same. And the workers who made these products were, in the view of these critics, little more than slaves to machines, doing the same thing all day, everyday. Mass production was seen by some as a symbol of all that was wrong with the world. It was criticized by Aldous Huxley in his 1932 novel, Brave New World and by filmmakers like Charlie Chaplin in Modern Times from 1936.

Defenders of mass production retorted that the high wages paid by mass production factories meant that workers could afford more products themselves. They pointed out that mass production created a great number of useful things that more people could afford. Therefore, they said, it improved people’s lives.

For most people, the doubts about mass production, which intensified during the Great Depression, were swept away by World War II. Mass production created incredible volumes of equipment for the war effort. Most manufacturers switched production to war materiel. Many car factories retooled, and began to make airplane or tank engines. Using mass production methods, some factories turned out tens of thousands of guns per month, more than the entire country produced in a year before beginning the uniformity system. Meanwhile the cost of building some weapons dropped to as little as 20% of the prewar cost.

Interchangability of parts had become a basic law of manufacturing. During the war smaller factories often made just one part, which was combined at a second factory with parts from many other factories. At the same time, part sizes were becoming more specific. The holes in engine blocks often had to be precise to within thousandths of an inch. Such engineering and production advances were unprecedented, but as the war demonstrated, mass production also made mass destruction possible.

Mass production today

Mass production has become far more sophisticated than at its inception. To increase productivity, managers have focused on planning and scheduling. Actual production has become a carefully managed flow of parts, materials, and employees. Sales and marketing have become part of production, enabling management to know how many copies of a product to make.

One of the most important innovations is “just in time” production. Invented in Japan, the process requires detailed, predictable transportation and manufacturing schedules. Materials required for production arrive just in time to be used, while products are

KEY TERMS

Assembly line —A sequence of workers, machines and parts down which an incomplete product passes, each worker performing a procedure, until the product is assembled.

Interchangeability —Parts so similar that they can be switched between different machines or products and the machines or products will still work.

Machine tool —A machine used for cutting or shaping parts.

Uniformity system —A method for building products out of interchangeable parts that arose in the United States during the early nineteenth century.

manufactured just in time to be shipped to their destination. This process cuts down on costly storage in warehouses, and prevents obsolete products from building up.

Computers have played an important role in planning and keeping complicated schedules that may involve thousands of people and parts. They help figure out production flow as well, keeping track of how much time different tasks take on the factory floor, and how much space they require.

In some ways, mass production has become so sophisticated that it is no longer true mass production. Many products come with a variety of options, and customers can choose any combination desired. When buying a computer from some manufacturers, for example, customers can specify the size and make of the hard drive, how much memory they want and other details. Many theorists see a time in the near future when clothes are customized too. People would have their measurements taken, and when they order clothes, the clothes would be cut to their precise size by lasers at the clothes factory. The product would be created by specialized labor with the aid of machines, each shirt or pair of pants would be made using the same process, but by virtually any definition, this no longer would be mass production.

Resources

BOOKS

Hindle, Brooke, and Steven Lubar. Engines of Change. Washington, DC: Smithsonian Press, 1986.

Scott M. Lewis

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