I taped a magic marker to the z-axis and ran the sample circle g-code. It looked very round, so I figured that I'm in good overall shape.

The big issue I have now is due to the warping of the table when I welded along the length of the frame. The cross-members that support the steel being cut aren't level with respect to the gantry (they are all at different heights). I'm wondering if there's a foolproof way to level them so I can do a test cut without a THC.