wwolf

Hey there, I know this is old but I had the same issue and this was the only thread I found on this issue in particular. I have the flow calibrated so I didn't want to just increase it in the slicer to mask the issue. After giving up on finding a solution online I started studying the layer printing path and I had a Eureka moment, it was an excessive retracting distance producing under extrusion, since the test I used to calibrate doesn't really show slight under extrusion problems I started looking for one that does Did a test print using this site http://www.retractioncalibration.com/ and found I am getting slight under extrusion when using over 5mm retraction distance (I was using standard 6.5mm). After changing it in Cura to anywhere from 4.5mm to 5mm (Bowden setup) everything was printing perfect! This makes sense since you got a bit of a better result after playing with combing settings. Worth a try. Note that after changing filament or the tension of the extruder's clamping spring, you might have to redo the retraction calibration, since the effective diameter of the extruder gear would change (Teeth dig more in some material). Also don't forget to do an E-Step calibration for the extruder motor.