number of blade groups:17

number of blades per set:34

Oerlikon makes vertebral gear machining tools
Tool Design Principles
In the cutting of the teeth of the oerlikon tool, the projection of the blade on the end face of the cutter head is not the center of the cutter head, but tangent to an offset circle. When the tooth radius is not corrected, the inner and outer cutting edge radii are equal to the nominal radius. There is a certain angle between the inner and outer cutter teeth, which is coordinated with the cutter tooth radius to control the tooth thickness of the processed gear.