<p>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.</p>

<p>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).</p>

<p>Does this sound like a sound plan?</p>

It is hard to determine the exact source of the problem as there are few possibilities (I am assuming that you have a single nozzle and only one filament in use):
One of the hardest issues for me to get on my printer was fact that my auto-level sensor was mounted about 0.5mm too high - so please check that as this will give you a bit higher Z than expected.
Printing speed matters  - for some prints I was slowing my printer to 20% of nominal speed to get adhesion
a hair-spray layer or a masking tape on the bed could help with getting the grip
also you could play with nozzle temperature de/increasing by 5 degrees and see how it is going