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How Automotive Metal Cutting Works

Automotive Metal Cutting Technologies

Automotive metal cutting uses many of the same techniques and technologies as metal cutting for other fabrication industries, like shipbuilding.

For small, low-volume jobs that don't require super-precise accuracy -- for instance, the type of metal cutting done in an auto enthusiast's garage -- the tool could be as simple as hand-operated cutting shears.

But for higher volume jobs, or for those in automotive manufacturing that require very precise cuts, the equipment gets more complicated. For instance, computer-controlled lasers, plasma cutters and waterjets are commonly used for a number of reasons:

  • They can cut through lots of material quickly.
  • Computerized controls ensure that there are few mistakes.
  • The greater accuracy helps cut down on waste, and therefore, reduces costs.

In the highly competitive auto manufacturing industry, suppliers of auto components are always looking for tools that can save labor without sacrificing quality.

Here are some quick snapshots of how the precision heavy-duty cutting tools work:

Lasers: Lasers work well for cutting sheet steel up to 1/2-inch (1.27-centimeter) thick and aluminum up to 1/3-inch (0.9-centimeter) thick. Lasers are most effective on materials free of impurities and inconsistencies. Lower-quality materials can result in ragged cuts or molten metal splashing onto the laser lens.

Plasma: Plasma blows an ionized stream of gas past a negatively charged electrode inside the torch nozzle. The metal to be cut, meanwhile, is positively charged. When the gas contacts the metal, it creates a superheated area between 20,000 and 50,000 degrees Fahrenheit (11,093 and 27,760 degrees Celsius) that slices through the metal [source: Rupenthal and Burnham].

For cars to look and perform their best, their metal parts have to be cut within very narrow bands of accuracy called tolerances. To find out about advances that are improving this accuracy, go to the next page.