hob

tool

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Last updated

June 29, 2026

Quick Summary

A hob is a specialized tool with a projection used for cutting teeth on gears and worm wheels. This cutting process is known as hobbing. Gear-hobbing machines employ a rotating, multi-tooth hob to generate teeth on various types of gears, including spur gears, worm gears, and helical gears. This method is highly efficient for mass production due to its continuous cutting action, which results in accurate gears at high speeds. A gear hobber is a machine specifically designed for this milling process. The term "hob" can also refer to a projection at the back or side of a fireplace used for keeping things warm, or in British English, a cooktop.1234

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machine tool
Gear-cutting machines
…multiple-tooth cutting tool called a hob for generating teeth on spur gears, worm gears, helical gears, splines, and sprockets. More gears are cut by hobbing than by other methods because the hobbing cutter cuts continuously and produces accurate gears at high production rates. In gear-making machines gears can be produced…
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…multiple-tooth cutting tool called a hob for generating teeth on spur gears, worm gears, helical gears, splines, and sprockets. More gears are cut by hobbing than by other methods because the hobbing cutter cuts continuously and produces accurate gears at high production rates. In gear-making machines gears can be produced…
Read More