After completion of one or two teeth, the blank and cutter stop feeding and the cutter is withdrawn and indexed back again to its starting position, thus allowing a short rack cutter of a practical length to be used. Cutter is again fed back to depth and cycle is repeated. Amount of teeth is gear rack for Machine Tool Industry china controlled by the device gearing, and pitch and pressure position by the rack cutter. This technique can be used for generation of external spur gears, being ideally fitted to cutting large, dual helical gears. For making helical teeth, the cutter slides are inclined at the apparatus tooth helix angle.
The hob is fed in to 
This methodis specifically adopted to cutting large teeth which are difficult to cut by formed cutter, and to cut bevel-gear teeth. It is not widely used at the moment.
In gear planing process, the cutter consists of true involute rack which reciprocates across the face of the blank and the blank rotates in the correct relationship to the longitudinal motion of the cutter as if both roll jointly as a rack and pinion. At first the cutter is definitely fed into complete tooth depth with cutter reciprocating and blank stationary. Involute shape is generated as the blank rotates and involute rack cutter feeds longitudinally.
In the other technique, both roughening and finishing cuts are taken with single pointed tools. The usage of the formed tool for finishing is definitely impracticable for the larger pitches which are completed by a single pointed tool. The amount of cuts required depends upon how big is the tooth, quantity of share to be taken out, and the kind of material.
