I have come to the end of the new features in Simplify3D Version 4! The last feature I will be covering is called “External Fill Customization” and allows you to specify the angle at which top & bottom layers’ infill are printed.
This is useful if, for aesthetic purposes, you want all the external surfaces of your print to have a uniform or specific direction of filament, even when those surfaces are at differing heights. It could also be argued that you could increase the strength of a part by dictating the direction of the filament on the external layers. Simplify3D allowed you to set the internal infill layer directions in previous versions, so this new feature brings you the option to do that with the surface layers too.