Print out the set and use 1.75mm filament to make an axle. I used a lighter to heat the end of the filament then slightly crushed the end in the axial direction to make a 'head' to keep the blades on the shaft, the other end just jams in the hole in the base.

You may need something to hold it down if the breeze is too heavy, like tape or a weight. It works fine for me, but it doesn't take much breeze to knock it over or spin it around.

Note: The zip file contains the original SolidWorks 2010 files.