Rough top surfaces and ugly lines

Bambu Lab P1 Series Troubleshooting
1

Hi all,

My daughter’s birthday is coming up and I wanted to print a cake topper. I played a bit with 3d lettering and then printed it, but I noticed the really rough surfacing. I took in account on the model that it should be in increments of 0,2mm as this was my layer thickness. I applied my standard ironing to it (Top surfaces, Rectilinear, speed 20, flow 30, spacing 0.1, inset 0.21) that usually smoothens out the top surfaces but I still get ugly lines and rough surfaces in some spots.

Does anyone know how to prevent these?

Thank you in advance.

Kind Regards,

Eef

Mije10Jaar.3mf (68,1 KB)

20250415_154847
20250415_1548471920×864 30.7 KB

20250415_130500
20250415_1305001920×864 155 KB

2

Recalibrate the printers and auto bed leveling should help. When was the last maintenance?

3

Thanks for your reply!

I do bed leveling on every print.
Last maintenance was on the end of January (Lubricated the z lead screw and wiped down the carbon rods). After that I ran full calibration. I changed the nozzle this weekend.
I ran filament calibration again this morning, it made little difference unfortunately.
But on other prints (not self modeled) I don’t have this issue.

4

It is overextruding.

Think about it. Your flow ratio is about 95% or 0.95, same for the top layer, yeah? Then you top it up with 30% more when ironing. The excess plastic has to go some where, yeah?

5

Hi,

I downloaded your file because, funny enough, I was suddenly having the same problem myself. As you can see from a print of your file, I have a rough print.

I tried to think back to when this first started happing, and after a day of rewinding my memory (a great “Black Mirror” troupe, I realized it was when I had to print with a rubber filament for the first time. After doing an initial configuration, and saving it to the printer, I saved it as a separate preset, before eventually going back to printing with my regular PLA. That was it I believe!

When you save a new preset, after defining it during a calibration, it seems to me that the printer is not saving presets the same way the Studio is, but instead keeps only on “K” value on the printer. When you go back to a different filament preset, the printer still uses the last calibration settings saved to it, so if your “K” value is different for the flexible filament, your regular filament preset will still use that, even though you have defined filament settings for each.

To be on the safe side, and to rule out any other config concerns, I loaded me regular, basic pla and configured my calibration to that, and the printer said that it is saved to the printer. I then reprinted your file, and it appears to be correct.

If your have done a calibration recently, especially for a new filament, do it again, by printing the lines, then the square wafers, and save that setting to your printer, before printing you file, with the same filament again.

This is why I like to stick with just one filament source. Usually with my Anycube Basic, I can change to any colour while keeping the same profile. With the flexible filament, it was a different manufacturer and a completely different texture, and that is what I had saved into my printer, before saving the proper one back.

I have had my P1S for a few years now, and I can tell you all, for anyone that is a maker and know their way around mechanical things, I have never had a serious problem with this machine, and consider it a workhorse!

It has never had a problem, no matter how daunting it appears, that I have not eventually been able to fix myself.

But, I never update anything. Ha!

6

IMG_5173|666x500

7

IMG_5172|666x500

8

Hi Wingmaker,

Thank you for your reply. I will check this out in the afternoon and see if I missed something on that.
But when you say that you ‘save setting to your printer’ how does that work? Cause I set the K value in the Device tab and I select the profile for the filament in the Prepare tab after calibration, but how do I get these values to save on the printer then?
I always thought the K and filament profile were going to be sent to the printer with the file (like in the Z-code or something), but that’s not the case?
I have only yet printed with PLA so far, tho from different manufacturers (Bambu, Elegoo and Polymaker) and I have calibration profiles for every manufacturer (and a seperate one for PLA Silk)

Your M print does look good and way better and the way I would want it to be ofcourse!