Squaring up the base

Hello, I’m brand new to the CNC world. I am currently trying to build my Pro4848 and I thought I was doing well until I measured the diagonals for the base. Okay, I thought, 1/4" off isn’t that bad, little finesse here and there. Nope. I disassembled it and rebuilt it, twice now, and still, the same measurement once everything is fitted properly. 81.75" x 82" Am I doing something wrong? I’m frustrated that I cannot get this thing square!

Three thoughts…

  1. Skip finesse and go right to brute force; that machine is heavy and needs quite a shove to square it, or a long clamp. Loosen the bolts, over-correct, tighten.

  2. If you’re picky, measure the ends of each cross beam to see which are off-true and by how much, and flip half of the bad ones over so they cancel each other out.

  3. The end stops will take out any remaining error by truing up the motors themselves regardless of the frame shape. When you home the machine, the two Y motors are homed at the same time but independently to their stops, so you can tweak parallelism there.

Thank you! I was thinking that if it is out of square, it would jam up the motors, so I felt I HAD to get this right. I’m heading back into battle with it, and bringing as much brute into brute force as possible!

Even way off square, the machine will likely work just fine - it will just produce off-square results.