Extrusion: Underextrusion on same areas in model

[veedee 4]

Hi Guys,

I Have my new heated bed for UMO installed and working. I also installed a 0,8mm e3d nozzle in the original UMO hot end. The rest of the setup is standard.

Now I'm getting some kind of underextrusion problems with prints. But I can't find out what it is. The underextrusion seems to occur on the same places when I print the model multiple times. The filament color doesn't seem to be the problem either (Colorfabb PLA/PHA)

*Link removed*

Does someone have any idea what the problem could be?

Thanks

 

[veedee 4]

Problem solved.

Tensioning the X AND Y motor helped. The undertension of both created some kind of repeating pattern of lines not touching and lines overlapping each other.