My extruder keeps mashing the filament

Bambu Lab P1 Series Troubleshooting
1

I have a P!P, for the most part it has been fantastic.

However, it keeps squashing the filament between the two holes in the extruder. I have replaced the extruder, the hot end, tried different size nozzles and it keeps happening.

So each time I have to take apart the print head to get to the extruder, take apart the extruder and then pop the yellow wheel and the rest of of the bits out of there. What I find is that the extruder has mashed or ground the filament to a blob wider than the hole it goes out of. I snip the filament on either side of the blob, remove all the filament, and reassemble the whole thing.

Only for it to happen again after maybe one or two good prints. If I’m lucky.

I have used a variety of filament and had the same problem. I keep it in a dry box with desiccant, use a active dryer, tried brand new vacuum sealed rolls of filament.

I was so frustrated that I bought a A1 mini. That little thing works a treat. I just can’t afford to replace my P1P, and I am done with buying replacement parts for it.

BTW - Why does the P1P have cable connectors that allow you to plug them back in incorrectly? Gah! I loath the “Hotend fan speed abnormal” error with a passion.

2

Do you have pictures? My printer doesn’t do that at all. The most I get are small grooves on the filament, because of the AMS.

My guess is that the extruder or the hotend is somehow mounted incorrectly. You mentioned that you replaced them, so it might be related to that.

This guide explains the disassembly very well: Extruder Maintenance Guide: Cleaning and Lubrication - P1 series | Bambu Lab Wiki

Check that all bearings are present and that you tightened the long screw all the way. Another thing to check is that your gears spin freely and don’t bind.

3

I have to disassemble it again tonight, so I will take pictures and post them.

It mounts to the print head with three screws, so I don’t see how I could improperly mount it, but lets not rule out my ability to mess things up.

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4

The problem you are experiencing is called Heat Creep.

First, it is recommended to confirm that the hotend fan is running when printing, or if it is dirty / clogged. Start by cleaning the fan and ensuring it is running as expected.

Next, it is recommended to check the back side of the extruder and confirm if it feels very hot to the touch. If the extruder motor overheats, it can lead to extruder clogs as the temperature in the extruder will increase.

The recommended guide by luro02 in the previous post is a good suggestion, as cleaning and lubricating the extruder can ensure the motor is not overheating by trying to turn the extruder gears. A simple test is to try and turn the yellow gear of the extruder manually, while the printer is off, to confirm if it is hard to turn or not.

Please also check the Heat creep and how to avoid extruder/hotend clogs to learn more. If you are printing in a hot envirnoment, this can also be a reason for the extruder clogs.

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5

Thank you for your response, I will look into this.

I did lubricate the extruder as per the instructions in the guide that luro02 linked, still had the same issue.

I do have an enclosure on my P1P, I will try running my next PLA print without the the top on the enclosure to see if that helps.

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