The Pros and Cons of Fully Ground Root Fillets

The article "The Pros and Cons of Fully Ground Root Fillets" appeared in the August 2014 issue of Gear Technology.

Summary
For maximum life in carburized and ground gearing, I have been advised that fully grinding a radius into the root gives maximum resistance against fatigue failures. Others have advised that a hobbed and unground radius root form is best. Which is best, and why?

Keywords
root fillets, ground root fillets, grinding, shot peening, basics

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