For many thin wall objects it makes sense to print reinforcements, stringers etc. as separate objects who melt together with the surrounding shell.
For some thin wall objects it makes sense to print reinforcements, stringers etc. with a continuous zigzag line, i.e. the extruder turns 90Â° inwards, moves e.g. 2mm, and returns to continue with the outside shell (saves weight and printing time). Even if drawn with only 0,01mm distance, there is a groove of about half a millimeter on the outside of the object.
Its not an issue with the Zortrax slicer, its the same with S3D.
Why is this? With a drawn gap of 0,01mm one would expect that on the outside shell only a seam would be visible.