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Zeeman
(@zeeman)
Active Member
Filament change problem

on Prusa mini when i try to change filament it ejects old filament without any issues, probably in half meter length, but when I insert the filament and initiate the feed it feeds a very small amount of filament and I have to click "more" option number of times. It appears that this process only feeds filament each time for (maybe)  some 20 mm. How do I fix this so that lot larger portion of filament is fed to the hotend?

Posted : 08/12/2023 8:21 am
_KaszpiR_
(@_kaszpir_)
Reputable Member
RE:

Make sure that new filament is cut under sharp angle, so its end is like an end of a needle - it helps to push filament and move around the internals.

When you load new filament make sure to push it really well so it goes to the extruder. When pressing load it should be transported to the hotend.

If you need to press the key multiple times then your Bowden tube between extruder and hotend is just too long and you need to shorten it. https://help.prusa3d.com/guide/how-to-replace-a-print-head-ptfe-tube-mini-mini_142572

 

See my GitHub and printables.com for some 3d stuff that you may like.

Posted : 09/12/2023 8:21 am
Zeeman
(@zeeman)
Active Member
Topic starter answered:
RE: Filament change problem

loading the filament through the bowden tube and filament sensor to the extruder is correct, I can feel when filament hits the extruder and when extruder begins to pull the filament. But what you sad made me think; this printer came with prusa filament sensor as an add-on. I am thinking now, maybe that extra length of bowdwn tube to filament sensor is the issue? Maybe that needs to be changed somehow in settings? I got to look into this. Thanks for the advice.

Posted : 09/12/2023 8:27 am
_KaszpiR_
(@_kaszpir_)
Reputable Member
RE: Filament change problem

Filament sensor should be before extruder and it just detects if the filament is ending so the printer can pause print because of it.

The fact that printer loads filament and then you need to push extra key to push it forward may be a sign that the bowden tube between extruder and print head is too long or the pipe between where bowden tube enters the heater and then gets to the end of the heated nozzle is too long or maybe the nozzle is dirty or there are some obstructions in it.

Time for maintenance cleanup?

See my GitHub and printables.com for some 3d stuff that you may like.

Posted : 09/12/2023 8:06 pm
Zeeman
(@zeeman)
Active Member
Topic starter answered:
RE: Filament change problem

brand new printer, assembled just a few days ago, it has original filament sensor that was assembled per instructions. I will play more with it. thanks for help.

Posted : 09/12/2023 9:29 pm
_KaszpiR_
(@_kaszpir_)
Reputable Member
RE: Filament change problem

Another thought that maybe it I related to filament grinding, bit this usually ends in other printing issues during print.

Inspect the filament surface when you load it and unload it - it should have only thin marks from the extruder, and no chunks eaten away with it, which would be due to extruder grinding because it cannot move filament.

See my GitHub and printables.com for some 3d stuff that you may like.

Posted : 10/12/2023 9:08 am
Zeeman
(@zeeman)
Active Member
Topic starter answered:
RE: Filament change problem

thank you for the tip!

Posted : 10/12/2023 8:09 pm
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