Hello, everybody! Forgive my english! I have a P1S from 2023, to which I have always done all the ordinary maintenance. For 2 days I have been having problems retreating the filament from the “Extruder Filament Sensor”, because the PLA+ remains stucked as in the pic. This happens with PLA+ Elegoo, in multicolored prints that last many hours. I’ve already had to throw away 10 keychains in printing because of this problem. The cutter, recently changed, cuts the filament well but if you look at the pic, the filament is like “enlarged” and the gears are unable to push the filament upwards. So, I have to disassemble the entire extruder, because otherwise I cannot release the ptfe on top of the extruder. Why does this PLA bulge happen? I suspect it’s the Elegoo brand, because it only happens with this PLA+.
I also had to buy a new Extruder Filament Sensor, because I carelessly broke the spring :tired_f
I always print with the door completely open, but I’ve never had this type of problem with the brands I always use: Sunlu, Esun, Eryone, Bambu. So I suspect Elegoo PLA+ glass transiction temp., is lower than 65 °C. I’m using textured PEI plate (Jupinee textured sheet) and I always used 65 °C for better adesion on the heat bed, but I’ve never had these problems with other brands. I will try to lower bed temp. to 60 °C, because top cover is used for AMS.
Leaving the lid on will do it. Hot air rises. The filament path is along the top of the printer. So it gets a nice long pre-heat before it even gets to the extruder. If the ambient temp is a little higher, that might be all it takes to go from OK to jammed. If your AMS is on top of the printer, print a “riser” that’ll let you run with the lid raised up 10mm or so, so that the heat rising to the top of the machine isn’t trapped and doesn’t build up.
This is definitely heat creep IMO. Your heat block fan might be gettin old and showing signs of needing replaced if you see this recently and frequently with no other real changes. But overall, for PLA, I’ve had great luck with vented glass risers. It lets you keep the AMS on top and still let hot air out.
Thank you all for your answers. You are very kind! A while ago, I printed “Sliding Vents Riser V3- Modular” riser which allowed me to open and close the air slits. Unfortunately, when I printed ABS, I noticed a heat leak (with closed slits) and I had to remove it and put it on every time I had to print ABS. So I decided to remove it permanently. But I’ve never had heat creep problems. After reading the heat creep article and better understanding the glass transition temperature, melting temperature and Vicat temp, I can conclude that it is a fault of the Elegoo filament’s Tg, beacuse is lower than 65 °C. Why do I say this? I’m printing multicolors keychains. PLA filaments loaded into my AMS are: Bambu Lab, ESun and Elegoo. Black and white Elegoo PLA are the only ones to create heat creep, given that I had previously printed the first copies, with black and white Sunlu. Anyway, I cleaned the heatsink and the hot end fan thoroughly, which had a not too excessive dust accumulation. Now I just have to wait for a new filament sensor (to be delivered) and reassemble the extruder. I’ll try to print a minimal riser, to keep the lid open. Thanks all for your answers.
