For 3 years now I've been using a second-hand KuKa KR 100-2 P 2000 shelf robot, with a KRC2 control system. I use it to do various milling and trimming jobs on rather large panels. You can see a video here:
However, until recently, I never mastered this robot, not even after installation. In hindsight, this is probably a rather large mistake. However, I managed to get quite decent results with this setup. Throughout the years, the calibration asjustments I needed to make in the program grew larger and larger. In pursuit of more accurate milling results, I recently bought a dial gauge and an adapter to master the robot by hand, and was surprised by the results. I really should have done this much earlier.
Now to my question: As i've said I noticed that the robot mastering slightly drifts. I had to readjust several points in my program about every 3 months. Is this normal? I'd like to remaster the robot instead of figuring out what adjustments have to be made in the future. How often do you remaster a KuKa robot?
Could it be that this drift away from the mastered position is because I shut down the robot after each work day, and start it up in the morning? I've had the idea that the drift got way worse during the unusual hot summer we've had here last year.
Thanks in advance for your replies.