I’ve been printing with this printer now for a few months, getting pretty good with it, def getting to know the nuances.
I just don’t think it’s worth it to worry over the small tolerances, like you would for a CNC machine, as long as it’s as close to level as possible, the nozzle doesn’t drag etc. then everything sort of levels out after the first few layers anyway…
There’s just too many factors preventing a perfectly level surface( like to the thousandth)…ie, thin aluminum bed warps, flex in the 10mm rods, minute shifts in the frames geometry etc.
My technique now, assuming the frame is “perfectly” square. To sqaure off Z, I measure on left side, from top of 10mm X-axis rod to the bottom of the top frame extrusion, then repeat for the right side, until perfect. That way I know that as Z rises, it will most likely want to stay square, vs. trying to align to the aluminum plate or the glass bed which could technically be slightly off to begin with, more chances of warp in the aluminum plate etc. Essentially I’m squaring using the component that would have the best tolerance, ie, the frame extrusions…
Then after that, since I know sliding left and Right along X, the nozzle is all squared I can then square the bed to this. I center the bed to the nozzle. Use the paper sheet method under the nozzle to get a nice even slide all the way across. One sheet for .1-.15 layer heigth, doubled up sheet for .2-.25 layer height etc.
Then, after that, since you know everything is squared along Z and X, you center the bed again with the nozzle and slide along Y, back and fourth, using the same method as above until you get a nice snug feel with the paper underneath all throughout the slide…
It’s like riding a bike, little difficult at first, but just becomes second nature…agai, the whole idea being that you’re trying to use the components with the least amount of error when starting out the squaring process…I used to square off of the glass, or aluminum plate with descent results but it was a little more tricky, the problem also being is that Z wouldn’t often not end up being square to the frame, which meant that there was more potential for it to go out of alignment over time, especially if building taller models, which I notice, did happen a lot more often.
hope this helps…