I've posted this to reddit before, but the post has gotten lost among an automod flurry. I've got some longer travel coming up and this thing has been on my mind again, so I'm looking for some suggestions!
The irony of precision calibration, if you loose calibration you loose calibration and you’re never getting it back.
If you measure 3 times accurately enough, you’ll get 3 different answers.
I’m just saying taking the UBL leveling a step further and actively compensate for out-of-squareness in the frame. This would allow some out of squareness as long as the frame was rigid. The alternative is squaring everything as you put it together.