Irregular walls: Which issue do you think was the real culprit?

Hi,

I want to start by posting a picture which demonstrates a problem I had with my printer and how I solved it, but I am trying to pinpoint the main culprit, so that I know what I am doing, in case it happens again.



The prints I was getting looked like the one piece on the rightmost part of the picture. There were obvious irregularities on the walls. It wasn't Z wobble, as it wasn't periodical. Also, it wasn't due to an inconsistency on the Z axis movement, as whenever there was a protursion on the wall, the opposite side was recessed, so basically the layers were randomly shifting on the X axis. It never resulted in major layer shifts where the print had to be stopped (so it happened in both directions occasionally and somehow compensated the problem) and it seemed to favor certain movements of the head but it wasn't consistent accross prints (it didn't happen at the same layer heights).

The general solutions suggested for similar problems were about the belt tension and structural consistency of the printer, so I started by tightening the X belt as much as I could and also increased some of the motor voltages as there were some suggestions about missing steps. I never heard any motor sounds suggesting missing steps but went on and increased them slightly. This is when I got the object in the middle. It was much better but there still were irregularities. I wanted to add a printed belt tightener to further increase the belt's tightness but I couldn't put it in place (the tightness of the belt prevented it), so instead, I've increased the motor voltages some more (I tried to feel the temperature manually, so that the motor was hot to touch but not so hot that I couldn't hold it more than a few seonds). I've also tried to tighten the bolts on the structural parts and the motor's pulley. This resulted with the objet on the left side of the picture. I believe it is aceptable in quality.

The question is, was that related to a single problem, or a compund problem, due to the interplay of a few issues. The fact that I couldn't increase the tightness of the belt anymore but still got better results suggests me that the belt's tightness was not the main culprit and low motor currents could be the real problem. However, wouldn't I hear any missed steps due to the motors not working with enough amperage? Or shouldn't it cause more severe problems, where layers would shift massively?

Thanks...

Edited 1 time(s). Last edit at 03/27/2021 11:10AM by drmaestro.

Loose drive pulley? Overtightening the belts might add enough friction between the pulley and the motor shaft so that it stopped slipping. Just a thought.