Found this in an email from Harvey tools that was sent to me, thought it might be of help to those that are new to CNC machining.
Optimizing feed rates and adjusting IPT are vital to maximize performance and tool life. Learn which formulas to use when machining internal and external circular tool paths with this helpful guide.

Circular Interpolation: Machining Circular Tool Paths - In The Loupe - Machinist Blog

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