Hi Tom
Happy new year and best wishes for 2015.
I am having a positioning issued with the y axis of my cnc router. The drive is a delta ac servo asda-b2 with 1.5kw power that is being run in velocity mode.
The issue I have is that the width of the cut part exceeds by 1/16 the width that it is supposed to be. This issue affects all the parts and the issue is constant for the entire length of the part (94 inches in this case).
I am using a 1/4 compression bit cutting 5/8 inch melamine at about 200 ipm and 9000 rpm. The encoder gives about 16000 ppr and the axis directly drives a ballscrew. The problem also happened with other bits and at different speeds.
I re-tuned the drive and kflop and got kflop to within about 60 pulses of error when tuning at full speed. I also set the max output, integrator and error at 2047.
I verified the pulses per inch both with a caliper, a ruler and a tape measure on longer distances and I am dead on when not cutting. The x axis is also dead on.
Also, the parts are rigidly fixed to the table with 1 1/2 screws to ensure they will not move.
I am attaching the g-code file and my init file.
The y axis drives the z-axis and there is no loose in the ballscrew nut or assembly or other mechanical parts from what I can tell.
Any ideas what this may be caused by or what to verify? The issue has been driving me nuts for the last 2-3 weeks.
Can it be that klop looses counts with the encoder.
Thanks in advance.
Darren
