Previously, I’ve had very successful prints. However, after swapping to the 3d printer from the laser, I calibrated the bed, put in a new spool of plastic, and am seeing this very odd printing problem, notably near the end of the bed. I tried loosening and tightening the screws for the heated bed in a start pattern at a low lb of torque (just tight enough, not “good and tight”) since they are just machine bolts.
It’s almost as if it is sputtering plastic.
Here is what I’ve done:
Fiddled with tightness of heated bed bolts
Replaced hot end
Replaced plastic (both plastics two different brands, PLA, and did the same exact thing)
Using default 3d filament settings in luban for PLA.
Calibrated x3 using the card given with machine (can pull card out of hot end tip, but pushing forward causes it to make an “arch” in the card).
Picture below of this weirdness. Again, I have gotten multiple good prints before.
I calibrate with the card like you mentioned, then print a 0.04mm square across the bed (I have an Original with a small bed). I usually have to adjust a corner or two until the print is good.
I used the live z-offset button on the touchscreen and the print immediately got better.
I’m beginning to think the auto calibration is just not reliable, as the bed isn’t super level for whatever reason. The front appears to be higher than the back part of the plate. I’d say it’s warping due to the heated bed. The center prints well always when I use the card as I have, it’s the outer edges that suffer.
Adding my experience here: My print bed is bumpy like hell (Kickstarter version), and if I want to use larger areas of the print bed, it requires careful attention. With the single extruder head, I do a 11x11 bed auto calibration (only possible via GCode, not via touchscreen). I never wait 30 min’s for getting the bed hot - with my machine the heat-up does not change the bed significantly. Even calibration with cold bed is good enough. what is important to find the sweet spot in Z-offset. So like others here suggested, use the manual Z-offset control to dial it in - for this I use the skirt or brim, watching while this is laid down that i adjust Z so that in the places the bed is slightly lower the plastic just sticks, while in the places the bed is slightly higher, it is not squiched down too much. With that, I usually get even larger prints successfully done.
Ignore that I ask for heated bed calibration there - as I said, in the end - at least for me - it turned out not to be that important. YMMV.
And last remark (judging by your pictures most likely not the problem here, but for completeness): if you have inconsistent filament feeding, the feeder wheel may be worn off: Inconsistent Layerlines - #39 by Blackavid
