Well, you need a hobbing machine. They are certainly more rare than lathes and mills.
The thing I worry about is the elevated pitch circle. Once I had to outsource primary transmissions for racing motorcycles. I had everything sorted out, according to industrial standards. The manufacturer, who was experienced in this (and also in hardening) told me, that standard sizing, for the small gear, would make the teeth to vulnerable. The correction for low tooth gear weakens the base. An extreme example is the ancient roll dryer, used for drying clothes. The design (roll dryer) allowed only for four extreme corrected and vulnerable teeth. When you see one, look at this detail.
So he designed within the dimensions his own pitch circles and hobbed the special gears with a standard hobber. These gears never broke down and a championship proved he was right. Knowing this, and putting your caliper here and yonder, you see this is widespread. Transmission gears are high-stressed components. |