I have had a terrible problem with bad resonance with the Z Axis on my CNC Lathe. The problem only appeared at certain feed rates. The lathe has smooth operation at most feed rates.
In desperation, I had to try to program around the feed rate that I wanted to use (0.25mm/rev) to avoid the resonance; as it was affecting the quality of turned parts. I.e. I would use a non-ideal 0.15 or 0.35mm/rev to avoid the problem.
I tried all the advice that I could find on the internet to no avail. I even changed the Stepper Motor and Stepper Motor Drivers to a different makes. No luck. I tried varying the Power Supply Voltage to the Driver with absolutely no effect.
I then tried a mechanical approach by adding a flywheel to the Z Axis Stepper Motor. Bingo!!! Why didn't I do this 3 years ago? So simple and so effective!!!
The video shows a wobble in the flywheel which resulted from my poor hand tapping skills. I will make a new flywheel when time permits; now that I seem to have the problem licked.
The flywheel is Ø99 x 14 thick and made from mild steel. There was absolutely no maths used; rather a simple application of the laws of physics and gut feel!!!
See video here
http://www.youtube.com/watch?v=mqCL7g4gwAURegards
Chrisjh
Machsupport Forum
