Hi, I am trying to drill an array of small holes. The holes are .004 dia on .005 centers and the array is 15 x 15. I have a small custom CNC machine with 12000 step Servomotors driving 5MM ballscrews. After drilling and inspecting the patterns I notice positional errors throughout the patterns on the order of .0002 which I calculate as 12 counts on the stepper. I have attempted to tune the system many times using the Galil Tools to no avail. I've tried "Auto Tune" , Manual Tunings. Is there something I'm missing such as velocity or acel-decel rates? I will sacrifice speed for accuracy. PS I am a novice at this. Thanks
Galil_AndyH on 06/02/2009 - 09:06
Do you have any position error during your moves? Use the Scope to look at the position error when you are performing your drill patterns. If you are seeing the 12 counts of error during the drill patterns, then it is position error. If you do not see any position error during the moves, then it is a mechanical problem.
Also, you indicated "12 counts on the stepper." Did you mean servo/encoder instead of stepper? If you have stepper motors, you cannot tune them.
FTM628 on 06/12/2009 - 14:09
Hi Andy;
Thanks for the reply.
Yes there Servo/encoders.
I'll try and see if I can figure out how to use the scope real time as I'm drilling.
Thanks.