Hobbing can be described as the manner in which gears, sprockets etc are made on a machine specifically designed for this purpose. The teeth are cut at regular intervals using work pieces through a string of cuts by using a device known as a ‘hob’. As compared to other methods to make gears, this is a lot cheaper method that can be used to make a wide range of quantities and parts. Moreover, it is highly accurate and reliable. Most of the users use the process of hobbing to create spurs, gears etc.. Since it is fast to work and not very expensive, most of the gears are cut using this process.

A machine used for hobbing is used for hobbing containing two parallel spindles; one mounted on a hob while the other is mounted on a void work piece. The angle present between the various spindles of the hob’s spindles and its relation with the work piece’s spindle differs. The actual difference depends on the product being manufactured. If a spur gear has to be made, the hob is fixed at an angle that is equal to the hob’s helix angle. On the other hand, if the gear being made is a helical gear, then there will be an increase in the angle of the hob as that of the angle of the gear. A proportional ratio is determined and rotation of the shafts determines the exact quantity of teeth on the blank.

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