My 3D CAD and additive manufacturing experimentation at Texas State led to this cool gadget! If stuck on a lightweight dowel, can you make it fly? its a 3 inch outer diameter The holes are for 1/16 inch screws, 3 or 4 self tapping ones should do the trick! I don't know much about fluid dynamics, but the sweep angle looks right. I'm printing one soon - if you beat me to the punch let me know how it works!Make sure it is laying flat on the side without the holes. I have it scaled to print at 76.2 mm (3 inches) in the X or Y direction (uniform scaling ON), but feel free to blow it up! The wall thickness may become an issue if too much smaller. STL file was saved with max chord length of 1 and max angle of .25.