So, I produced this quick paper accordion model  to go with the paper bellows but it does nothing beyond looking pretty. 

I really wanted it to make a sound. Proper accordion sounds are impractical in a project this size but a bit of discordant whistling would keep me happy. 

To the drawing board!

I've learnt through my various past experiments that a whistling pipe needs a tapering blow hole blowing air over a slot. I fitted some baffles inside the hex box (black lines above) to direct the air and fitted a tapered blow hole lined up with a suitable slot. The result: perfect whistling! 1046hz according to the app on my phone. Roughly a 'c'  two octaves above middle 'c'

The downside being the big sticky-out-bit on the side of the box. I wondered if I could fit the tapering tube inside the body of the hexagon.

And so we have this. Air, to be provided by bellows, blows though the hole in the side of the box through the tapering tube and across the underside of the slot at the top of the picture above.

Once assembled and with the glue dry the finished box sounds a nice clear whistle. I'll make another with a different note by moving the baffles inside to change the volume of the resonant cavity and fit that at the other end of the bellows.

With the bellows in place a quick test shows that everything is working nicely so far…woot woot!