I stumbled into a youtube video from Nathan Builds Robots (https://www.youtube.com/watch?v=UFyAyV3ddT8&list=PLpOlkqVluSBLgVwdOLiaS0-DnX68qM2iE&index=7&t=130s) that showed a simple adjustment that seemed to significantly improve the print quality on my printer. Before making the adjustments, most of the prints were ok. The calibration cube was off by .1 to .2 mm in the x and y and a benchy was ok. In the first part of the video he suggests the following:
Loosen the allen screws on the coupler for the stepper and belt synchronization rod at the top back of the machine.
Adjust the two belt tension if needed on each side.
Tighten the coupler
After doing this simple step the cube was dead on and a benchy was very good indeed. I concluded that there was a slight racking between the two y axis belts that threw things off slightly.
Nathan has a couple of other, far more involved mods in the video which i don’t want to take on. But others may be tempted. Just thought I would share this tidbit with the community.