Problems with filament unload
I'm new on PRUSA MINI+ and maybe i'm missing something.
When i try to unload filament, i can't do it as it's really hard to extract (i have get it forcing with tools, but i don't think is a good idea).
I don't have this problem when the filament is ending and the printer start the filament change session, so when the extruder is hot and working... but when i try to unload it with a cold machine i never get it out easy.
Am i missing something?
The printer is new (some days) and has a filament sensor.
Thanks
RE: Problems with filament unload
When you choose to Unload filament, printer will first heat-up the hotend to desired temperature (depends on what type of filament was loaded last). That it, when extruder actually starts to unload, hotend should be hot enough.
Or am I missing something?
[Mini+] [MK3S+BEAR]
RE: Problems with filament unload
Yes, this is what i did, but i did 3 unload after switching on the printer and the result is always the same: a filament that it's almost impossible to remove.
Now i try with a different procedure
1) pre-heating (PLA)
2) purge the filament
3) unload the filament
In this case i success to take it off... but i'm not sure it's something correct.
RE: Problems with filament unload
So, if I understand correctly: when you select Unload, hotend starts to warm up.. does it reach filament temperature? You mentioned PLA. In this case unload process should start at 215°C (if I remember correctly). If that's the case and extruder still can't pull filament out, then you should findout where actually the filament is stuck:
1. Check extruder (if filament path is clean inside and if gear on motor shaft is tightened properly)
2. Take hotend apart and check inside heatbreak if there's any filament residue (but in that case I would expect you'd also have troubles with printing).
Btw. try to be precise with terminology to avoid confusion:
so when the extruder is hot and working
-I assumed you mean hotend (extruder doesn't really get hot).
[Mini+] [MK3S+BEAR]
RE: Problems with filament unload
I have run into a similar issue. New Mini+ with filament sensor. When I've unloaded, it is filament that has been in for a while and the machine cooled down. I run the unload command and it heats & then says ramming to form an end, then unloads. When I pull the filament out, it gets stuck in the sensor. I've been able to pull it out holding the sensor body and pulling harder, but it always pulls the little bit of PTFE tube out and I see the filament end is a bit of a mess. It's been mashed and is a larger diameter, so won't pull through that last bit of PTFE; cut the messed up part off and it comes out clean. Then I replace the PTFE in the sensor and load normally. It seems that ramming process isn't really working well. Sounds like a purge is needed before unloading cooled-down filament.
Mini+ (kit) - Revo Micro | Antler Cooling | WiFi (4.4.0RC1)
RE: Problems with filament unload
Yes i solved the problem in this way. Since i started purging the filament i have not had any problems.