Problems with printer - help

Bambu Lab P1 Series Troubleshooting
1

Hi Guys,

the print quality is getting worse every print, starting 2 days ago.

i have been printing the same parts, with the same filament some time now. but now the top layer (I use ironing) has defect during printing. even swapped filament that has been dried before, but didnt make a difference. strange thing is that it is not consistent on the complete part.

So i printed a testpart, which i have a previous printed part of, and it failed in a specific area (see attached images). it’s a circle, and the left side of circle is perfect, but right side looks like attached picture.

Steps i took to try and solve issue: try to change filament settings, did filament calibration, changed filament, cleaned nozzle, swapped hotend, replaced ptfe tube to toolhead, did the bed leveling/tramming, checked extruder gear, adjusted tension, ran full calibration of printer.

I have no clue anymore how to fix this. Can there be another mechanical defect on the printer itself?

I noticed some play in the toolhead and the x-axis carbon rod assembly, but I don’t know if that is always the case.

When I print a circle, the left side of the circle looks good, but the right side looks terrible. I know for sure that this was ok before because I printed this part numerous times. But not only the circle is bad, other object surfaces too.

I print small and large circles, all flawless and perfect. I was very happy with the P1S and its print quality but all of a sudden things start to get very bad.

I sell these items, but at the moment I cannot print anything until I find a solution.

Bambulab P1S
0.20 standard setting + ironing concentric 20% line distance 0.22mm
Filament: bambu basic pla red + bambu matte pla black

top is old part, bottom is new printed part

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2

Is it just on circles or everything? You might set 12 or so rings or squares spaced evenly across the bed and see if it only happens on one part of the plate or if it’s on all the parts. Does it show up on circles only but not squares, if so then it’s probably in the travel mechanism…There is a wiki on setting belt tension. But, I would decide if it’s a deal killer before I started messing with all that.

3

hi, thanks for your reply. it’s not only rings it’s on other surfaces too, but that profile was the easiest to print to test; Because i print those alot (normally with some art inside) i know what to expect what i should get as output. this ironing was concentric but i use rectengular ironing on larger surfaces. it’s doing that on larger surfaces too. i even re-oriented the ring to check if it was the model or the printer, but it happened in the same position, so it isn’t the model.
tried a smaller ring, so 2 fit on the plate, top right and bottom left, and they both had it in the same place on the model.

i’ve already set belt tension. Cleaned the rods again, that helped a little, but still not 100% as it should be.

i will try to print some evenly spaced cubes and check if that gives some more insight, but it looks like it’s the travel direction that gives issues.

4

So i printed a test pattern, 30x30mm 0.6mm thick squares. evenly spaces across the bed.
the results of this test where the same as what i’m experiencing when printing models.
The left of the bed has perfect quality. The quality worsens further to the right. and middle right (nr. 8) its very rough and bad. i rated the quality from 1 to 5. 5 being the best.

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5

Have you done bed tramming? Manual Bed Leveling / Manual Bed Tramming | Bambu Lab Wiki

Also how about flow calibration? You know, 1.75mm +/-0.03 is about 3.4% tolerance.

Just a tip, when you do diagnostic print, turn off ironing. Ironing away the imperfection of the top surface won’t help you diagnostic your problem.

6

Yeah done the bad tramming several times now. Checked belt tensions. Calibrated machine. Cleaned all rods.
Bambu sent me a first layer test and this came out good. Also printing looks good. But the only problem that started a few days ago is the ironing issues im having.
I calibrated the filament too. Flow calibration and pressure advance. Thats why the diagnostic print is with ironing.
The left of the bed has perfect quality, and the right of the bed has bad quality.