Gear Materials
Numerous nonferrous alloys, cast irons, powder-metallurgy and plastics are used in the manufacture of gears. However, steels are most commonly used because of their high strength-to-weight ratio and low cost. Plastic is commonly used where cost or weight is a concern. A properly designed plastic gear can replace steel in many cases because it has many desirable properties, including dirt tolerance, low speed meshing, the ability to "skip" quite well and the ability to be made with materials not needing additional lubrication. Manufacturers have employed plastic gears to reduce costs in consumer items including copy machines, optical storage devices, VCRs, cheap dynamos, consumer audio equipment, servo motors, and printers.
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Famous quotes containing the words gear and/or materials:
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—Robert Burns (1759–1796)
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—David Elkind (20th century)