I have built the robot and ran thru calibration and created a pick and place program. Issue is after 100 or so cycles the robot seems to be off in the J1 joint and in the Z (height). I did not do a fine calibration. Should I have? Everything is locked down so the arm is not moving over time especially in the Z(height). What did I miss?
To see this working, head to your live site.
I would definitely set a fine calibration position so you have a good reference point. The limit switches are not as accurate as a fine calibration point. You will also get some break in on the gear boxes as well as belt and chain stretch. I would check your tension on those.