Hi,

I proceeded and adjusted the spring tension of my AZ GTi and play of the gears. I managed to basically get very very minimal backlash in both axes (particularly the RA axis, where the reverse RA calibration points are right on top of the forward RA points, quite amazing). Also managed to get decent guiding in RA y great guiding in DEC (with occasional runaways) after having struggled for long time with crazy bad guiding performance (5 arcsecs and more RMS). Running 3.37 controller firmware. Axes are a bit more stiff now, and not homogeneously smooth, unfortunately (with some harder points), but hopefully smooth enough.

What I am concerned now is how jumpy it is the RA axis. With the DEC axis, I manage to balance out jumpyness/oscillations and runaways by adjusting the aggressiveness down. I managed to get around 0.5-0.7 arcsecs yesterday. However, with the RA axis I don't manage to reduce those jumps, the best I got was 1.2 arcsec but often it was more like 1.7 arcsec. Also, if the positive oscillations seem to have a 'double peak', which I'm not sure where it comes from.

Do you have any suggestions on what I could check to improve that axis?

PS. The polar alignment procedure is amazing. I have never been able to achieve such a deadly precise PA that quickly in my life !!!.

Your guiding looks pretty good for AZ-GTi! (to me).
Should be adequate for the RedCat.
Can't help you as my guiding is not better.
I myself got so frustrated with AZ-GTi's guiding (I used to use it with AT72EDII with or without a reducer) so I upgraded to RST-135 for travel.
Still happily using AZ-GTi with 180 mm and below, though. Usually without guiding / computer control. Just SynScan / SkySafari.