[Résolu] Underextrusion above 1 cm  

Underextrusion above 1 cm

Hi,
I got my MINI about 10 days ago, it seems to be R2 with fixed cables. First week, it printed great. Then I wanted to change filament (both where Prusament PLA), which went wrong (got stuck in PTFE tube, now I know the trick with purge and unload immediately after), then couple of prints were ok, but now, when I want to print something higher then about 1 cm, it starts underextruding above that height. What helps seem to be manualy bumping nozzle temp to 220 C, but it strings a little, and does not completely fix the problem.

Any ideas what might be causing this?

Some facts/ideas:

• I'll try to clean the feeder and nozzle tonight (cold pull). But is it normal to do this after 10 days of use?
• No clicking sound. Or very minimal, like one random click every 5/10 minutes, and can't say what's the source.
• The room with the printer is a but dustier then normal, there are some renovations in progress in my house, so maybe the fine dust might cause the problem?
• The nozzle and MINDA probe seems ok, there is like 5 mm of this thin tube (heatbrake?) visible.
• I'm new to this 3D printing stuff.
• First layer is always perfect.