So I'm trying to get my printer to a point where i can pretty consistently turn out high quality prints, but I'm at a point now where i get results like this. These two prints are from the same batch, same print job, and I'm completely clueless on how to fix it. I have an ender 3 v2 with a bltouch, I've adjusted the eccentric nuts, tightened the belts until the tips of my thumb and index finger couldn't tighten them any further, bed is level, using hatchbox pla. I know i can do ironing to fix the cosmetic problem, but I'd prefer to fix the root issue if possible.
I thought I’d add that it looks like it’s overextruded. So much that the filament is being “pushed” out and curling back around the nozzle.
It could be the e steps, flow rate, etc but it could also be that your Z offset needs to be adjusted back away a smidge.
That could be part of the inconsistent print since the tool head movement over one section of the bed vs another may be affected by the layer below based on how the filament curled there.
If you want to do a deep dive into adjusting/calibrating the Ender I did write up a bit here (although that post does relate to Klipper and I mention settings/adjustments for Klipper it starts purely with the physical printer itself and builds on it)
This is going to sound stupid, but don't forget to activate bed levelling after performing the leveling measurements. Maybe this is a stupid idea but I put M29 L1 and M29 A at the start of my gcode to load the ubl slot 1 mesh and activate it. Before getting ubl I used M420 S.
I spent way too much time frustrated by bad prints before I learned that leveling wasn't active.
Not sure how it works with your printer, but with mine on Klipper, after bed leveling I have to save and restart the firmware, and then I have to go back and select the profile that I just saved, otherwise it doesn't use it.
If those 2 are from the same job its either a sagging gantry on an ender or the bed/mesh is not tilted properly or not meshed/leveled properly. Check squareness and sagging gantry, then check mesh/level after.
Belt tension should be tight enough that you can strum it and hear a tone. It's possible to tighten a belt TOO much, which causes extra stress on the motors. This would result in the motors being physically very hot. However if these were both printed at the same time, that wouldn't be the issue here.
I wonder, how level is your bed? Yes yes, you have a bltouch and all that, but you still need to manually get your bed relatively level. Were these two prints next to each other or on opposite sides of the bed? How did the other prints in the same batch compare (like was there an obvious pattern of failure from one side to the other)? The bad print looks to me like the nozzle is too close, so it might be interesting to see what your first layer looks like in a test across the bed.
Even in the good print there's some blobbing at the end of each path and the main surface should be the same height as the walls around the cutouts. Did you calibrate your E-steps? It kinda looks like you're pushing out a little too much filament. depending on your slicer options, you may also check acceleration to slow down the head at the end of each path, which can help give the whole path a more uniform output.
One other consideration, although not as likely... Warm up the bed and check to see if all areas feel like they're about the same temperature. If part of the heating element went bad then maybe you're over-heating one part to compensate for a lack of heat on the rest of the bed. I only mention this because the bad print looks like it has a slant to it, but that could be an illusion of the photo.
I have a glass bed and I'm using the tramming function with the mriscoc firmware to give me depth readings for each of the four screws, and I usually reign them in to about 0.04mm range. Parts close to each other tend to have similar but not the same results, and i think the patches are too small to be from bed leveling, usually only a couple centimeters.
I can redo esteps, i can see what you mean about the overextrusion. I only set my esteps to the number recommended by the manufacturer of my extruder, but i haven't measured it myself yet, maybe that's a bit silly of me. Though if that's the problem then I'm still curious why it's different in different areas.
I can check out acceleration too, i looked up what acceleration and jerk meant at one point but it didn't make much sense to me at the time.
Yeah that's a pretty tight range for the bed leveling, shouldn't be causing any issues then. OK another possibility here... the failing prints, are they on the left side, right side, one specific corner, or does it tend to move around between prints?
E-steps varies per extruder, not per manufacturer. What they recommend will get you close but there will always be some variance. On my printer Creality recommended a setting of 93 but my measurements put me up around 98, so quite a difference. Are you still using a bowden tube style extruder or did you upgrade to a direct drive? And is your filament spool mounted on top of the printer (if so, what guides have you added for the filament path), or did you move it off to the side?
Erg sorry, jerk is probably what you're looking for here. It's been awhile since I did much printing so I keep confusing the terms.
Others have mentioned, but looks like 1st z is too low and it's squishing the lines together on that top right widget.
If there's a corner of the bed that's a little higher that could be doing it. The touch is supposed to ameliorate leveling, but I would check the mesh and see if it is crazy bad
What kind of bed do you have? If your bed isn't flat this can happen as well. I scrapped a magnetic PEI sheet because it was never gonna be flat enough for a whole smooth first layer for me
Creality bases are notoriously NOT flat although I've heard their quality has improved over the years. I have one of the 1st-gen Ender 3 Pro machines with a terrible dip in the aluminum base. One nice thing about a thicker bed material is that you can use discs of aluminum foil the shim the base. I started with a glass bed and 13 layers of foil to get the glass reasonably flat. I have since moved to 3mm G10 with a PEI sticker which is working pretty well (in case you want to try PEI again). I found some scrap G10 material on ebay and chopped it with a table saw, sanded all the edges, then got a PEI sheet that was 10mm wider than my bed to allow for some slop. Putting down the stickers is a lot easier if you have someone helping you. Then trim the overhang and you're ready to go.