I have been doing good quality prints on my Ultimaker 2 from the beginning, (I have it since about four months).
But since a while I started to have under extrusion on most of my print and that was append with any filaments I have (all my filaments are from from ultimaker)
Also I was using the same settings of before, when my print was good.
I tried everything I can to fix it, changing the temperature of the nozzle, the bed and many settings.
I made a lot of atomic method to clean the nozzle, I dismounted the nozzle to checked the teflon.
I also tried the alternative feeder from Robert and printed a bowden hook to try to improve the flow.
In the same idea I removed the spool and unwound the filament to reduce the tension, after I read that here :
All of theses things wasn’t really a success and the under extrusion was stil there !
I was wondering what can be changed on my printer, and after one week of testing I remember I did a firmware update (15.02.1)
Then I Downgraded to the firmware version 14.12.1 and magical! Since I did the downgrade I did not have anymore obvious under extrusion.
Is someone know or/and have the same issue ?