Balloon Propeller

Just a fun way to distribute spit around a room. Won't make balloons go further, higher, or longer than just releasing them a capella, but if the fan is attached it spins it in rather an amusing fashion. Kids love it.
Recommend using a bag clip from your kitchen (or 3D print one, if you will), to secure the neck of the balloon once inflated while you fiddle the nozzle and prop on. OR, you can unscrew the propeller, inflate the balloon with just the nozzle in, then choke it with your fingers while you screw the propeller back on (easier).
I printed these with 1 wall layer, and 10% infill. Seems to work. On my printer (with it's floppy tolerances!) I had to drill out the centre holes to accept the screw.
Oh, and you'll need a small screw. And a screwdriver.

The propeller works best if the bed side is facing the airflow. If using it for this, that means closest to the balloon. If remixing for other models (those foam planes that you throw around is one use), well, flip it.

Anyone is a