Ive built the MPCNC and its 36"x32", quite a bit larger than my big laser and the 3D printed parts are put through hell and back on that machine. Lulzbot is known for 3d printing the majority of their parts for their printers, those printers make astounding parts. I’m not saying its not the 3D printer parts, but I don’t think the forces that are being exerted on the 3D printed parts, nor the temperature changes are what is causing these patterns. My mounting plates and axes remain tight over the course of my runtimes.
That being said, I’m taking the advice I get here seriously, and don’t want to write off any observations and recommendations as not applicable.
I’m starting to think that there are certain parts of the bed/axes that are more susceptible to vibrations. That’s why when I said it works one day and not the next, it’s really because one day I was working in one area and the next day I was working in another area.
Edit: also electrical. Not sure my previous problems have been fully alleviated: CO2 Laser Interfering with stepper motors - #48 by James_Harding