Knife blade sheath with vent to evaporate the water remaining on the blade

The structure of the walls allows ventilation and is obtained with a simple printing technique. The sidewalls are eliminated (wall loops =0) and used as a model for the interior of the sidewalls (sparse infill pattern - rectilinear or aligned rectilinear). For the 'pink' model I used rectilinear aligned and I had to set a density of 20% to have a better grip at the top. The sidewalls are 3 mm thick from the design as can be seen in the FreeCAD files. In Orca Slicer you can see the parameters in detail in the 3mf files. I used PETG.