How to cut a large spur gear with a prime number of teeth?
for a description of a method for large prime gears. Some shops use differential machines routinely to cut helical gears of all sizes because it is often thought that helicals are difficult on a non-differential machine. CPC-HOB is a PC computer program that makes this job simple. Accuracy is equivalent to a differentially cut gear since both machine types require change gear sets to create the helical angle.
