I would expect that the foils should be designed so they are hollow with a wall width that of your Extrusion width and the sharp points should be of an ending diameter of the nozzle/Extrusion width. Asking a 3d printer to print threads smaller than the extrusion width never works well.

You may want to redesign this so it is in multiple parts and glue them together after they are finished rather than trying to make it on structure..