Scraping noise and quality problems on walls

[user_1517080186]

I’m not new to 3D printing and i recently brought a Bambulab A1, and it usually prints beautifully (compared with my old Anet A8).

i’m having trouble printing Card Shuffler card holders correctly, reached a certain height (probably change in the geometry) the 3d pritner makes a weird noise when it prints the walls which are not precise.

This seems to happen more with thin and tall models, I succefully printed the other models of the project almost perfectly excepet for the body
The interested model is in the second plate

I tried several times:

• The first time the print detached from the bed, with Bambu PLA basic profile
• The second one was interrupted by me after seeing the walls, with Generic PLA profile (reduced speed) and increase brim
• The third time I decreased cooling from 80% to 60% and in the middle of the print selected silent print speed (50%), the noise has reduced but the same quality

I can’t understand why there is a scraping sound on the second and third wall

The back side is almost perfect while the front seems not bonding together

Video
Slow motion

I’m using Bambu Studio 1.10.1.50 on Windows 10
I’m not very familiar with the Makerworld platform and I adapted the AMS version of the project to work with single filament: i’m using Creality Ender PLA filament

CardShuffler_noAMS.3mf (external service because it says it’s too big even if it’s not)

Thanks for helping

[OTpandy1]

Looks like a massive over extrusion.

Things to try:

1. Calibrate filament
2. See if there is a preset for your filament other than generic.
3. Lubricate x and y axis.

Thanks,

OTpandy1

Happy new year! Happy printing!

[user_1517080186]

Thanks you for the fast reply

You are right, i did not calibrated the flow because in general I didn’t find it that bad

So i calibrated the flow using Bambu Studio, and it came out the flow to be 7% less than the Generic profile, the prints is slightly better but the problem is still there.

The calibration allow me to notice defects on the brim: it’s inconsistent, is perfect in one direction, there are gaps in the other

Then I printed this bed test.3mf (25,7 KB) and I guess that’s not normal especially if I have enabled bed levelling, only the right portion seems ok

What i have done so far:

• The axis are well lubrificated
• Yesterday I have done manual bed tramming, then I started bed level calibration but nothing changed
• It doesn’t seem the bed, the extruder and the hotend to show visible or excessive clearance

[BambuBanker]

Have you printed with anything other than regular PLA

[EnoTheThracian]

Since your flow was off: Did you dry the filament? I have found the Bambu’s to be more susceptible to moisture than prior printers while also the Bambu lab filament tends to be wet when having crossed half the world on the oceans before getting to me.

[JonRaymond]

I also think it’s because of the speed that the filament is printed at. Moisture wasn’t really a problem when printers were slow.

[OTpandy1]

Yeah, the only other things I can think of is drying the filament and slow down printing speed, like JonRamond said.

Sorry that I can’t help anymore.

Thanks,

OTpandy1

Happy printing!

[user_1517080186]

I think I’ve finally found the mystery…

After swapping the nozzle,I found that the 0.2 mm and 0.6 mm nozzles deliver a perfect first layer so I have investigated more on the 0.4 nozzle

Then I found that the 0.4 nozzle uneven worn-out even if I have not printed more than 2-3 kg of filament (the printer is brand new)

I think this happened while the printer was cleaning the nozzle on the bed

I have opened a ticket

The hole still looks fine

The area where the nozzle is cleaned

[EnoTheThracian]

Thanks for reporting back. Of course with severe and asymmetric nozzle wear, drying, new calibration, etc will not help much. But I would really not have expected that amount of wear on a new printer.

So thanks again for reporting back and on getting a replacement.

[GFox0622]

Let me know if you get any information of value about the nozzle wear down, I just replaced my .4 stainless on my A1 after 3.5 KG of filament which is way to early. The tip was worn out just like yours. I started mandating infill retraction in most of my prints thinking it was scraping the infill but I see why the cleaning process could also cause this. Trying a hardened steel nozzle this time.

[user_1517080186]

The Bambulab support said the nozzle is considered a consumable, so it is not covered by their warranty policy, but despite that they have exceptionally decided to replace the hotend with a new one for me anyway

That’s great but they don’t said anything more about the origin of the problem or how can I avoid it except to do a full calibration after mounting the new nozzle.

I still think that the cause could be in the nozzle cleaning at the begin of the print, maybe homed not perfectly or maybe the pei sheet misaligned by a millimeter.

Even if the Bambulab are precise machines why was a point chosen so close to the edge?

What’s happen if the nozzle is cleaned one millimeter closer to the hole of the bed?

There are some sign of wear on the edge

However I tried to recover the old hotend by using by flattening the nozzle with sandpaper as perpendicular as possible, and it seems to be working fine, probably I’m not going to use it for precision stuff or at very low layer height.

The previous test was completed almost perfectly (I don’t expect perfection obviously), now extruded plastic is squished back to the bed regardless of the extrusion direction

The old one after sanding

The old nozzle after sanding is less than half of millimeter shorter than the new one, i don’t think I reached the internal conical duct of the nozzle but the expected life is surely drastically reduced.

The new one for comparison