After completion of one or two teeth, the blank and cutter stop feeding and the cutter is withdrawn and indexed back again to its starting position, thus enabling a short rack cutter of a practical length to be used. Cutter is again fed back again to depth and 
routine is repeated. Amount of teeth is controlled by the machine gearing, and pitch and pressure position by the rack cutter. This technique is utilized for generation of external spur gears, being preferably suited for cutting large, double helical gears. For creating helical the teeth, the cutter slides tend at the gear tooth helix angle.
The hob is fed into the gear blank to the proper depth and the two are rotated together as if in mesh. One’s teeth of the hob cut in to the function piece in successive order and each in a somewhat different placement. Each hob tooth cuts its own profile depending on the shape of cutter , however the accumulation of these straight cuts produces a curved type of the gear teeth, thus the name generating process. One rotation of the task completes the trimming upto certain depth upto which hob is fed unless the gear has a wide face.
This methodis specifically adopted to cutting large teeth which are difficult to cut by formed cutter, and also to cut bevel-gear teeth. It is not widely used at the moment.
In gear planing process, the cutter includes true involute rack which reciprocates over the face of the blank and the blank rotates in the right relationship to the longitudinal motion of the cutter as if both roll with each other as a rack and pinion. At first the cutter is gear rack for Machine Tool Industry china certainly fed into complete tooth depth with cutter reciprocating and blank stationary. Involute shape is produced 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 utilization of the formed tool for finishing is certainly impracticable for the bigger pitches which are finished by a single pointed tool. The amount of cuts required depends upon how big is the tooth, amount of share to be eliminated, and the type of material.