Balloon Engine for Interlocking Toy Brick System

*This is a work in progress*

It's tricky to print a balloon rocket car due to the wheels and axels. So I figured "why not use the LEGO wheels we already have?"

Basically this is the mechanism for a typical balloon car but embedded into a custom LEGO-compatible body, so you can just snap it on to whatever LEGO vehicle you want.

Place a standard balloon over the lip of the "pipe" on the top. Blow through the rear nozzle to inflate.

I'm still working on variations - my goal is to showcase the differences in nozzle size for instance, so they can be used to help kids understand Newton's laws etc.