Idler Tension  

Eminent Member


Peeking through my PFTE tube, I see little teeth marks in my filament as it heads from the extruder to the hot end.  Is this normal?  Is my idler tension perhaps a bit too tight?  I desperately want to avoid clogging the machine, as the last time I did, I essentially replaced the entire hot end trying to get it clear, clean, and running again.

Posted : 29/10/2020 7:09 pm
Illustrious Member

Tooth marks are why the drive gears have teeth.  Normal. If the filament is flattening, then that's probably too much. 

It is always wise to get more than one opinion... as for trusting Prusa? No way man....
Posted : 29/10/2020 7:18 pm
Eminent Member


Thank you.  Yes, I’m seeing teeth marks rather than the deep gouges I saw before when I had a major clog.

Posted : 30/10/2020 12:51 am
-- liked
Trusted Member

This is how someone from Prusa Support showed me how to setup the idler tension

Special care should only be taken if using flex materials, because they are softer otherwise his advice was

Generally speaking - more tension should be better than less tension. Although, less tension is needed for example for the flexible filament 🙂

Posted : 30/10/2020 10:45 am
Alex Hung and Oxygen liked
New Member


video would be of great help in the instruction for the mini, or not?

helped me a lot to clearify how this setting should be 

Posted : 31/10/2020 3:59 pm
Trusted Member

The prusa-support-engineer knows about how helpful this video was for me and tries to get this into the official documentation 😉

Posted : 02/11/2020 10:42 am

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