Step 1: Calculator
The calculator can be accessed pressing CALC on the keyboard. AFTER hitting CALC select the softkey STANDARD/TRIG. Then use the keyboard to input numbers and operators (e.g. addition, subtraction, etc.) like a normal calculator.
On this model, the trick is to remember to hit the "STANDARD/TRIG" button to access the calculator. It is a time saver.
Step 2: Cutting Speed
1) Enter the diameter of the mill your using.
2) Enter the surface speed. (If it is not known, select the help screen, and a list of common materials with the appropriate surface speeds are given).
3) Press enter and the calculator will determine the appropriate RPM setting.