Random loss of layer quality

Good evening printers. Looking for help with the ender 3/3v2. Been printing steadily the past few months on an ender 3v2 and prints were more or less flawless. The past couple of days I’ve been noticing a drastic change in layer quality out of the blue. Layers are no longer uniform and are looking really gnarly.

I’ve changed the nozzle, cleaned out the hot end/ptfe tube, loosened and re-tightened all of the eccentric nuts, cleaned the z-screw and all rollers.

I’ve had a similar problem with an original ender and my last resort was to reconfigure all of my print profiles which kind of helped. However, since the files I’ve been printing haven’t changed I don’t see it being a software issue.

Sorry for the essay, but if anyone has some insights it would be greatly appreciated
I’ve added a photo with the very noticeable difference in quality

My guess would be to look at your extruder gears/rollers - has their tension changed or are any of the teeth broken of clogged with filament?

I know you had said you check your eccentric nuts and the like, but to me, it looks like the bed is loose.

Is the banding in X and Y directions or more pronounced in one direction over the other? The biggest test is to change nothing except slow it down, Drop your PR to 50% and see if the problem changes, Generally nozzle or hot-end problems will not change with speed changes however mechanical issues will change.

Doesn’t seem to be the gear/tension. Ran a feed test and that all looks good. Not much evidence of ware either from what I can tell.

Saw there was a very small amount of play in the back roller of the bed and gave it a tighten. Slowing down did help, but prints are still far from what they were a couple of days ago.
Inconsistencies seem to be unilateral in the prints.

It would seem like with even a small change it’s more on the mechanical side, and by that, I mean something physical has changed.

I mentioned earlier if it was more pronounced in one direction over the other or equal all throughout. The other part of this is if its a true shift. What I mean by that is , Located one layer that has a “bump” or “shift” in it, Follow that bump through your print to the opposite side, does the same layer have an indent opposite it or is it bumped there as well, Let me try to illustrate

EDIT: I am trying to get the diagram to look right, bear with me for a min. Pretent the X in the diagram below are spaces

Option 1

Option 2

Option 3

If that makes sense.
Kinda hard to draw on a forum but doing the best I can :slight_smile:

It would appear that each layer is off in a single direction each time. I ran the bed back and forth very slow manually and found a bump/flat spot, possibly on account of uneven tightening for the two bed screws. Re-adjusted everything and print looks good for about an hour, now back to the uneven layers. Better but still prominent.
I should note I ran another filament overnight with very clean layers. Just finding it odd I haven’t had an issue with the material until now

Sorry about yesterday was trying to put up some kind of a diagram to show what I was referring to, Got caught in a phone call

Option 1 is what I would call a Layer shift
Option 2 is what I would call an over extrustion
Option 3 I would look at the Z axis and see if the driver is overheating and “forgetting” to move up a layer

I never thought of drivers overheating, and upon further research it might be the cause. Will be looking into driver/stepper cooling improvements!
Thanks Jason!

No Problem, Let me know if you need anything else.

We’ll I’m not sure what the eventual fix was but I swapped filament for another project and the print was extremely clean. Now back to the problematic filament with no changes to driver/stepper cooling and the problematic filament is now back to near perfection. I am still going to look into better cooling as these steppers do run on the hot side

well, that’s good and bad at the same time… I don’t like those problems that you cannot say 100%, X solved the problem. It’s really only guessing at that point.

Just for curiosity does the new print have a large surface area? I am wondering if the mesh bed compensation is “working” less on the new print and therefore not working the stepper drivers as hard.

Hey Jason, sorry for the really late response. Was actually the exact same file as the one that was coming out with the layer issues. At this point everything’s been good regardless of filament or model. Keeping the fingers crossed that I can repeat whatever the solution was should this happen again :sweat_smile:
Thanks again for the help!

that is strange, Maybe a contaminant in the older filament that got cleared by the newer one? The main thing is it’s fixed but not knowing the 100% solution is annoying.