Bad Prints on 1 of 5 P1S - Any Ideas?

Bambu Lab P1 Series Troubleshooting
1

Background: I have 5 P1S Printers. 4 out of the 5 print great, no issues (using Fast PLA, same on all). The 5th printer (the newest I bought), started giving me grief. The top surface has voids in it (as if no filament fed) and feels chalky, the other 4 printers give me a smooth shiny surface. This is with ironing on. Without ironing, no chalky feel but I get a lot of pitting. I’ve attached pictures of a good print (same on 4 printers) and bad print. The firmware is the same, the file is the same, and the settings are the same. My guess was that the filament isn’t quite feeding properly or being obstructed somehow, but that’s just a guess. This is what I’ve tried so far:

  1. Re-sent the file
  2. Degraded the Firmware
  3. Re-loaded the Firmware
  4. Changed filament
  5. Changed the position of the filament in the AMS
  6. Calibrated and set pressure advance (several times and tried several settings)
  7. Installed a new nozzle
  8. Installed a new Extruder (stainless steel)
  9. Changed ALL the PTFE tubes
  10. Changed the Tool Head cover (with the fan)
  11. Printed faster, printed slower
  12. Cleaned the carbon fiber rods
  13. Cleaned and greased the z-axis rods and all stainless rods (z and y axis)
  14. Tightened the belts (several times)

Some observations.

  1. Watching the print I can’t visually see anything happening (no jerking, shaking, or ‘strange’ sounds, etc.)
  2. After changing the PTFE tubes, it got a ‘little’ better. The voids were less but the surface still felt chalky.
  3. I did find a short black screw in the bottom of the printer that I swear wasn’t there before. Tried looking for a place if could have come from, but there must be a hundred of them and can’t find any ‘empty’ place it might have come from.

Before I put in a ticket, I thought I’d reach out to see if anyone else has had this issue or has any suggestions I could try. Any help or suggestions would be greatly appreciated!

Bad Print:

Bad Print
Bad Print1676×1052 124 KB

Good Print:

Good Print
Good Print1607×762 98.4 KB

Hard to get my phone to focus so close, but I think it shows enough to get the idea.

2

It kind of looks like an over extruding issue. That might suggest that a stepper motor is failing just because you’ve tried most of the other obvious possible fixes. How many hours are on are printer?

Another thing that I have been doing, especially after multiple days/weeks of 24/7 printing is running the flow calibration at the beginning of every few prints. It seems to help. I didn’t see that mentioned as something you tried in your list.

3

Thanks, I’ve tried and adjusted the Flow Calibration several times and tried printing right after. The printer is about a month old and I probably have around 100hrs of printing on it. I think you might be right about the stepper. Sounds like I need to contact Support.

4

Yeah, that’s not nearly enough hours to merit a failed stepper motor. Might just be a dud. That can happen. The stepper motor may have its own PCB with an adjustable voltage pot on it. I wouldn’t recommend messing with that though without guidance straight from Bambu. I know my Raise3D printers have stepper motor PCBs with adjustable voltage and your problem aligns perfectly with that as a solution if the stepper motor isn’t actually bad, but being supplied incorrect voltage. I haven’t messed with any electrical components on Bambu yet and have around 500 hours on each of mine for what it is worth. A support ticket is the proper next move, but please come back and let us know what works for you in the end.

5

@Level23 Just submitted a ticket (my first). Will see what happens and I’ll post back if (or not) a solution is found or offered up.