Mortek: Each cutter has a best RPM to run and to find this RPM one needs to do an Impact Test. Once this is done, it only takes a few minutes when you have the equipment, you will know what suggested RPM and depth of cut to maximize, it will tell you what highest RPM you can go by calculating the SFM, then set your parameters for feedrate. See article - Chatter Myths in June - MoldMaking Technology for a more indepth explaination. Also see:
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