i have problems with the torch slipping at the far side of my table . I think its the x axis that is at fault i have adjusted the bearings for hours only to find that clearance changes depending on where the slide is on the rail . checked with a level across the top flat 90 degrees, it varies from 1/4 to half a bubble off from middle to end all this while my y rails are level .
when fast traveling in the x directions the lead screw vibrates when travel is near the far side stop. which i cannot get out
found the heavy duty coupler i had bought, that has taken out the vibration in the x lead screw. so that is a win there .
as far as the tube not square i adjusted the torch square to the cut surface although it will move somewhat in its travel its not much consequence on thin sheet . the problem seems to be the bracket from y to x rail is not holding square or parallel on the horizontal , the near fitment is better but neither are correct