Thanks for your input IMBoring25,
I've tried enought files over the last weeks to realize it's not the files (10+ maybe more than 20).
I'm using the old Cura slicer at the moment for parts that need infill but it's not allways possible,
for example the Ciclops parts has modelled support that is to thin to slice with Cura.
I've set the solid infill treshold down to 10mm^2 but it did not help either.
