I am having a little trouble with distortion with my PrintrBot Simple. The parts seem to be stretched/squeezed along a diagonal line compared to the X and Y axes. and it seems to be most noticeable when printing circles. I first noticed this when trying to print the MakerBot nut and bolt and noticed they didn’t fit together. Does anyone have any idea of how to correct for this?
Thanks in advance!
I’ve seen that caused by lose belts. Increase the tension on your drive belts… Er strings…
Could be caused by backlash elsewhere, too
Are your x and y steps calibrated?
@Jim_Wygralak I will try tightening them. The Simple isn’t that sturdy, so backlash could arise from shaky structure.
@Michael_Spano_Jr_Ama Probably not, since I have not seen that in any settings I have tweaked. How would I do that?
There is one other thing it could be, in your X-Axis, be sure that there is no twist from left END to right End, along the entire X-Axis. This symptom was very perplexing, but we solved a very similar distortion to the one you discribe.
By rechecking the entire geometry of the frame untill we found the twist. Once corrected, prints no longer showed that unusual distortion.
Loose belts. Even once you think that you have them tight… Tighten them a bit more. I recall when i was finally able to print circular threaded things that worked- i ea thrilled. Loose belts
Yep. Agree with everyone here. That is definitely backlash caused by loose belt/drive line.
Loose belts. 
Ok, thanks everyone!