First Layer Issues
Hello! I'm having an issue with my Prusa XL for a few weeks now and I still can't figure out what is causing this. The printer has been calibrated multiple times, has the latest firmware and is in good condition overall. I have tried various layer heights and image 1 has input shaper and image 2 does not. Both are 0.2 layer height. The print I'm using to test this is a 300x300 square first layer test that I've made. This issue happens only on certain areas of the build plate and in the photo its the lower right area of the plate. The print starts from the top right corner and makes a line that is very nice, then takes a turn to go down and that line is also great, then when it takes a right to go towards the lower right corner it gradually becomes less squished and becomes more cylindrical and once it makes two laps (of the outer walls) you can clearly see the gaps (which are again just noticeable on the right side of the build plate) which are not visible on the left side. I have tinkered with the extrusion multiplier, there is no clog as well. This is all on the first toolhead, the second toolhead does not have this issue. I've also adjusted the live Z option and it helps keep the filament more squished on the plate and look better but it does not help in the long run of the print. This whole issue has started to happen only recently and I have not done any tinkering on the mechanical parts of the printer nor have the slicer profiles been changed, the printer however has been used often and hasn't had this issue in the past.
Input shaper and layer height 0.2 SPEED:
Without input shaper, also 0.2 layer height SPEED:
I see there are probing 'zits' left on the build sheet. This indicates there was oozing during the probing sequence so the measurements may have been thrown off by varying amounts of unintentional padding. The commonest cause of oozing is moisture boiling off of damp filament and the steam pressure messing with internal pressure. Try drying your filament.
There are also fingerprints visible on the print sheet; they won't help adhesion 'though not involved on this occasion so cleaning the sheet is also a good idea.
Cheerio,
RE: First Layer Issues
I can understand the filament being moist though what is odd is that if that's the case, why does it happen on specific quadrants of the build plate? I doubt its the bed heaters being bad, looks more like a nozzle or z axis thing. The bed has those probing dots though its from recent tests so I didn't isopropyl it every single time. Again, the first line it prints to make the big square starts off nice and flat but when it reaches the right side of the printer it becomes more tubular/cylindrical, not as squished z axis-wise.
I'm going to be cautious here; specific areas of poor adhesion are often symptoms of greasy areas on the build sheet so clean the sheet, dry the filament and come back if the problems persist.
Cheerio,
RE:
Nozzle looks to far off the bed. You say it's been calibrated, but what does that mean?
How long have you had the printer and have you made any changes lately, aka changing nozzles etc.?
If nozzle 2 is fine then that eliminates any issues with the print bed imo.