Spindle calibration problems (lathe)

[SimonC]

Hi all,       I have been pulling my hair out for a few days ever since i tried the spindle calibration test in mach turn. before i ran the calib test my requested rpm and real rpm were about 150 rpm diffrence at some places in the curve and exactly right in others,but since i did the calib test i cant get full rpm and the requested rpm and real rpm are miles out. Is there a way to reset the calib test so its asif i never did it?   i did read somewere that deleting the liniearity.dat file will work but i tried it and it made no diffrence. also tried completley uninstalling mach and reinstalled it, saveing only the XML file with all my settings on but even that didnt work.

any advice or suggestions on things i could try to get it back to how it was before i did the spindle calib test will be much appresiated



regards
Simon

[Hood]

Afraid I have never used a VFD with Mach so cant help much but did you happen to keep the backup xmls? If so you could maybe try going back one or two.
Hood

[DaOne]

Have you tried closed loop spindle control? I got mine working and holding within 1 RPM. You will need to play with the PID settings.

[SimonC]

Ok i figured out why my spindle was acting all crazy. It wasnt a setting in mach,it was the power supply that im useing to power the 0-10v step/dir spindle board. i had switched the power supply for it when i was haveing problems with the index pulse and it was only getting 5V instead of 12v. anyway now its all working as it should.    I also tried the closed loop setting as suggested and now it holds to within 1rpm!.  with the closed loop setting i can see that even when there is a load put on the spindle,mach fights against it to keep the requested RPM perfectly!

Next hill to climb, setting up the tool table
wish me luck!


regards
Simon