I hope I can describe this right. If not, I uploaded a video and pic to oneDrive.
I couple of days ago my P1P started doing a weird series of movements when starting a print. Looking from front, it moves to back right corner, then front right, then diagonal back to the poop chute. When it reaches back there is a loud clunk like it’s hitting the stops hard. It’s not the flapper in the poop chute. It will then purge filament, then repeats the same movements. I also noticed that when it tries to clean nozzle tip it does it to the right of the worn spot on the build plate. The print never starts. The print head never ends up at front left anymore.
When this started I was on FW 1.07.X
So far I’ve tried the following, after each one I tried to print a benchy that has always worked, but I also tried another small model that has always worked to be sure. Resliced from scratch.
Check for damage anywhere (none)
Basic maintenance, belt tension, clean up, full calibration
Change nozzle (just in case…)
Upgrade to FW 1.08 and recalibrate
Factory reset and recalibrate
So far nothing has made a difference. Here is the link to video on OneDrive.
Printing the purge line line in the wrong place is a common means to detect a bent nozzle. Take a pic of it from the side to be able to check that easily.
Did you replace the internal PTFE tube or the chain link which is now shorter and constraint the printhead movement by any chance (or any mods that interferes with it?).
That is very odd! This has me confused as well! Have you changed the gcode at all? Also, have you tried homing the printer. Also, a wire could be unplugged for one of the parts that tells the printer when to stop, otherwise, put in a support ticket with bambu
If i send a print through Bambu Studio, it will do this ■■■■ and I have to cancel the print since it never starts. BUT, if i stop the print then print it from the cache on the SD card it works perfectly and prints. So the sliced model is fine. I’m at a loss, as is Bambu support.
Tried some other things with no improvement:
I went back to 1.08
Uninstalled studio and handy including deleting user data.
Factory reset on printer
Created a new account and linked to printer just in case something was coming from cloud server.
Put printer in LAN only.
Maybe there is something that restrics tool head’s movement, like seized pulley(s), loose GT2 gear (at the XY motor shaft).
My theory is, since the movement is too short before it hit the “virtual endstop switch”, it thinks there is something restrict the tool head movement so it considers homing fail, and thus re-issue homing command again and again, in an infinite loop.
But it doesn’t explain why starting the print from SD card success but not from bambu studio.
For this, my wild guess is some section of the SPI flash memory of ESP32 is bad, which section is forced to read write many times like EEPROM while flash memory should not. This should explains flashing different firmware didn’t fix the problem.
Another theory: when start the print from bambu studio, it runs those built-in gcode. But when start the print from SD card, it doesn’t run those built-in gcode. I can somewhat prove this: start the print from B.S. using AMS slot #3, but then re-start another print from cache it raises warning and uses AMS slot #1 instead.
So, when you start the print from SD card, does the print sit in the middle of the build plate like what shown in bambu studio or it is off to the right or left? This is to verify if there is mechanical problem or not.
