• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.
  • Some users may still have issues remaining logged into the forum. Please delete old bookmarks. If you are still having issues, go to the Site Issues forum here and let us know EXACTLY what you clicked on before the login issue arose, so we can try to track it down. We are working on this, and appreciate your patience. Thank you.


Basic CNC

January Project of the Month [3]
[10] Like what you see?
Click here to donate to this forum and upgrade your account!


Former Member
Former Member
Sep 29, 2014
Thanks a ton, last couple questions.
I've read a lot about tuning, but have never heard an explaination of what it really is.
Do you have a CNC for Dummies explaination for it and is this more to do with the CAD/CAM programs and is it something I could basically ignore for now in as far as using them for what would basically be power feeds ?
What would you say is a good speed range for Rapids ?
Lastly, do you have any recommendations for a controller for use in manual operation of servos ?
When you see a servo motor control out of tune for the first time you will understand, they tend to "hunt", rotating in each direction slightly on each side of the desired position, this can be a vibration.
As far as rapid speeds, go as fast as the drive will allow to a position close to the desired position as at maximum speed it will go past or short of the desired position trying to stop, usually past it due to the momentum of all of the combined components, then do a short feed rate move to where you want to be at a high feed rate then a move at the actual cut feed. I program 1990's early 2000's Bridgeport EZ Path lathes which have slow 100 IPM rapids, I rapid .025/.050" away from where I want to be then a .020/.050" IPR line move to position and then the actual IPR cutting feeds.

Many high end machines have "look ahead" capabilities, the software adjusts the feeds knowing the the hardware can't make certain abrupt direction changes accurately, making a 90 Deg. turn for example, in the car driving analogy it slows down for the corners (-:
[5] [7]