Title: P1S Cutter Arm Sticking at Full Compression After Clearing Extruder Jam

Bambu Lab P Series Troubleshooting
1

Hey everyone,

I’m hoping someone here has run into this before. I had a filament jam in my Bambu P1S and had to take the extruder apart to clear the clog. I got it all cleaned out and put back together, but now the cutter arm gets stuck when I press it in.

If I push it lightly, it moves, but if I push it in hard (simulating a full cut), it completely wedges itself in the depressed position and won’t spring back.

Here is what I have already checked and tried:

  • Swapped the blade: Put a brand new blade in, making sure it’s seated completely flush on the plastic alignment pegs.

  • Checked for debris: Opened the extruder back up and thoroughly inspected the travel channel. There is absolutely no filament or debris wedged in the back of the slot.

  • Adjusted the pivot screw: Loosened the black shoulder screw on the cutter arm in case it was clamping the lever, but it still sticks.

  • Checked the spring: The return spring is sitting perfectly straight in its pockets and isn’t bowing or catching on the housing.

  • Sensor check: The hall-effect sensor is connected and functioning fine.

2

Had the exact same thing happen. However I’m now only getting “bro, there’s actually already filament in me and I couldn’t possibly have any more filament. I’m just, like, so stuffed.”

I think it might be the spring in the clear section of the extruder, the part that has a magnet that tells you if there’s filament there or not. I’m actually currently on the hunt for what it’s called and how it’s meant to be positioned as I think it’s incorrect atm.

Did you figure out what was going on with yours?

3

What does it feel like when you SLOWLY push in cutter? What happens if you remove the nozzle and push the cutter in. Cutter moves across pathh above nozzle but below extruder assembly. Maybe back off a turn on the screw that releases the cutter as part of extruder removal process?

Very small gap between extruder assembly and nozzle and cutter is cutting right above nozzle infeed.