Notifications
Clear all

Filament gets stuck in the extruder  

  RSS
Susky
(@susky)
Member
Filament gets stuck in the extruder

Hello,

I have a lot od trouble with my Prusa mini+. From time to time filament gets stuck in the extruder. It is very annoying because it's very hard to notice from stream or any autodetect fail tool. I tried couple od time adjust this little screw in the bottom od extruder, clean every parts, but result is the same.

Most common situation when print is failed is when i'm printing some things and there is a lot of backing up filament during head moving. Some filaments are more susceptible to trouble (like silk), but today i'm stuck with some generic pla on which i have several dozen hours printed.

Can you please give me some ideas how to solve this?

Posted : 16/08/2024 11:24 pm
miko
 miko
(@miko)
Active Member
RE: Filament gets stuck in the extruder

Lemme tell you a story. I bought a mini back in 2021 or so. I printed with it and no issues on anything I wanted. Small stuff. One time, I decided to do a big print, like 5+ hours. I left it running while I went to work, like the manual tells you not to do. I came home to find a GIANT glob of dried filament surrounding the heatblock. I cleaned it up and was able to print again, but it was never the same. The extruder would click after about an hour of printing (or less) and would tear up filament. I replaced the bowden tube but found the weird olive crush rings to not seal right. I replaced the tube inside the heat sink, which had deformed for reasons unknown.

I decided, I'll just do small prints from now on. Shortly after that, the X-axis would get stuck trying to go up more than a third of the Z-axis. The bearings were so close to the extrusion that they were wedging into it, keeping the printer from doing tall prints. I figured, ok, I'll take this thing apart and get a mosquito hotend to fix their design flaw. And I'll convert it to a linear rail on the Z axis. I tore my printer apart, where it stayed that way for over 2 years.

I recently put it back together with a new mosquito hotend with a real all-metal heatbreak, good bowden tube, passthrough fittings to remove the break in tube, couldn't design a good linear rail carriage, so I put the normal ones back. I reprinted and got the extruder installed. I did a silicone mod to fix the horrific out of level bed. I got a tungsten carbide nozzle (the same one that prints gorgeously on my mk3s). The mini got so much love, it had to have been happy. I followed the build instructions thoroughly, with everything perfect and prints have been going great.

Tonight, I decided to put it through a real test and run a 12 hour print. Stupid me. 4 hours in, the extruder begins to click and chew at the filament. I figure, it has to be tension (like I had foolishly though a couple years ago), so I forced filament past the shred-zone and then adjusted tension on the fly. Seemed ok. A few minutes later, it was clicking again. I kept babying it and adjusting for another 5-10 minutes. Finally, the extruder had had enough. No adjustments took the click away. I cancelled the print. As soon as it cancelled, I thought I heard a pop, and the screen went white. I have turned it off and on and unplugged my pi (was using octoprint) and tried unplugging the printer and holding the reset. She ded.

The prusa mini is easily one of the worst 3d printers I have ever dumped money into.

So, you want to fix it? Sell it. Buy something else.

Posted : 02/09/2024 4:04 am
Diem
 Diem
(@diem)
Illustrious Member

https://help.prusa3d.com/en/article/regular-maintenance-mini_133222

And make sure the filament is dry.

Cheerio,

Posted : 02/09/2024 4:31 am
Share: