Originally posted on WWF by Tez2 on WWF 10th August 2009, 10:52 PM

Online calculator to calculate the RPM / Spindle Speed by entering the Feet Per Minute cutting speed and the diameter of the stock.http://janproducts.com/Speeds_and_Feeds_calculator.html

Also lists a variety of other available calculators including Bolt Circle, Screw Thread Data, Corner Distance, Tap Feed Rate and others.