A few days ago, my P1S extruder started experiencing underextrusion.
I tried the basics, like changing the filament, replacing the nozzle, and cleaning the extruder gears, without success, until it started making grinding noises.
I tried replacing the bearings, even though I thought it was unusual for them to fail after only 3,500 hours.
The noise stopped for a day, then returned the next.
I replaced the bearings again, and the noise stopped again, but the underextrusion problem still persists.
What could be the problem?
I’ve already opened a ticket for BBL to evaluate the situation, but I’d like to know if there are any other reports of this in the P/X Series and if it could be something more serious, like the motor itself.
I had the same issue. Mine turned out to be the extruder motor. Cheap fix but at the time I wasnt 100% sure so I brought all the parts possible for the tool head just in case.
Motor is fairly easy to replace. My advise, go through the process of changing the motor on wiki and once the motor spindle is visible try turning it by hand. Mine was really rough, clearly something had failed inside. Then you’ll be sure if its the motor.
For the umpteenth time, I opened everything today.
I cleaned and replaced the thermal paste on the current nozzle (even though I was completely sure it wasn’t heat creep, as I tested three different nozzles).
I cleaned and lubricated the extruder and replaced the bearings (I used the third and final pair of S693ZZs I purchased).
I lubricated all the axes (I had done this less than a month ago).
I lubricated the bearings and tensioned the belts.
I cleaned and lubricated the teeth on the extruder motor gear.
Oh, I also recalibrated the printer.
I tried printing, and everything is the same, with underextrusion regardless of the filament type used.
At least the horrible noise it was making seems to have stopped (well, at least today; we’ll see in two days, which is the average time it returns after each intervention).
It’s not logical that a printer with only 3,520 hours of printing in just under a year would experience extrusion motor failure. I’ve never printed at high speed settings; I always print between 50% and 75% of the speed (I’m conservative).
It honestly made me wonder if it’s worth buying another Bambu Lab (even though I ordered an A1 this week), which costs twice as much as similar printers here in my country and has parts that are also much more expensive than competitors, but doesn’t seem to have the same durability.
I’ve never heard it happening on X1/P1, only on H2D but can it be that the extrusion wheel is loose and slipping on its shaft and not following the yellow gear rotation?
It would be very unlucky for this to happen to two different gear sets. While I was testing the possible causes of the problem, I picked up another set to test, and the problem occurred in both. Today I also did a deep cleaning on one of them (mine), and despite all the manipulation I did, nothing moved.
I’ve got the same issue, but mine started on day 1 of ownership. Just unboxed my P1S, set it up, and printed the benchy. The very next print it stops extruding altogether and has the same grinding noise.
I’ve confirmed that rotating the yellow gear by hand does pull filament down, but once it’s hooked up to the drive gear, the grinding occurs. Seems like there is slippage on the shaft, or the motor is dead
Update, I definitely have a bad motor, and suspect yours will as well.
I took the three screws that hold the hot end assembly to the rest of the head out but left the ribbon cables connected. I turned the machine on and selected extruder “down” 6 times in a row while watching the drive gear spin. Not only did the stuttering and grinding still occur, but the direction it spins changes randomly (L,R,R,L,R,L). I took a video of the whole thing but the format is incompatible with the forum.
I just unboxed this today… how do I get ahold of Bambu for a new motor?
