Anet A8 - X and Y axis not square - how to fix?
I have an Anet A8 printer for about 4 months, set up pretty well (or so I thought) and printing a number of models pretty well. I made a large 3" x 6" box with a sliding lid yesterday and when it was done there was a gap on one side when the lid was slid on. I checked the parts and it turns out they are not square - which means the X and Y axes are not square to each other.
I'm wondering how to adjust this - I'm thinking that extending the distance between the back of the frame and the front by adjusting the threaded rods that separate them to a wider distance on the side where the angle is obtuse. Obviously one of the first things I'll check is that the distance between the front and back is the same (I can't imagine why I never checked that before, come to think of it).
Does this sound like a sound plan?
Please post a picture or two of the print. It may be a matter of slack in the drive belt(s) rather than the physical mounts of the carriage.
Ended up being rushed last night and didn't have a ruler of sufficient length to check the whole printer. I was able to determine that the distance between the front wall and the intermediate wall was exactly the same. Ruler wasn't long enough to reach all the way back.
I managed to print a 20 mm cube, and it showed that there was a difference of about 0.6 mm from one diagonal corner to corner than the other. Also showed my X dimension was about .2 mm thicker than it ought to be. Y was withing 0.05 which seemed good to me. Z was spot on. So it looks to me as though it's definitely skewed from X to Y. I'll know more when I can get a longer ruler on it. Then I need to figure out how to correct it.
Pretty difficult to say on such a small cube. Print this: https://www.thingiverse.com/thing:2280529 and measure the diagonals. Have you replaced the belts already? This is probably your main problem!
To correct x-y axis alignment to 90 degrees: Loosen the nuts on the two threaded rods at one end and in the middle. Lower the Z-axis to its lowest level. Place a square block of wood or metal so that it rests on the table and is snug against the X-axis rods. Slide the table so that either its rear or front edge is under the edge of the block. There you can clearly see any misalignment by comparing the edge of the block and the edge of the table. Now the 'fun' part: rack the entire assembly, pulling the diagonal corners to square the table and block. You may have to tape the assembly down to keep it in place while you spin the threaded rod nuts back into place....gently,then carefully snug the nuts while watching the table and block to insure they stay put!
Actually this worked and is pretty much what I ended up doing in a roundabout way. I added a set of braces on the frame to stiffen the front and back, and when I was done I checked the ends against each other diagonally and slowly tightened up the frame until everything was right and square. Now when I print objects they are coming out square or nearly so.