Tonight I got the rails “square” (measured out precisely, clamped, marked holes, center-punched, drilled, reassembled, and now the diagonals are off by 1/16″ — ah well; the holes are there now. There’s no going back. :v), and set the height (with a block, so they should be pretty good).
My z axis is mostly together. The four towers of the z motor mount were a little delicate, because they broke when I dropped it. (cough cough maybe that’s not what they were designed to endure.) I’m waiting on a print of the Hicwic universal tool mount to use to square up the z conduit. Unfortunately, the only PLA I have right now is Hatchbox, and it has been pretty weak. (The rest of the spool is going back to Amazon tomorrow.) Even after I get the universal mount printed in good plastic, I’ll eventually try to redraw it to make it a little beefier.