The Bicycle Bubble Machine

Full video: http://youtu.be/-RRaYNLv_Zs

Finally, be the star of commuter traffic! Make all the kids in the neighbourhood happy! Or just jealous! Engage in inspiring discussions with chemtrail believers! With the wind-driven Bicycle Bubble Machine drawing a dense stream of soap bubbles behind you, you too can bring peace and happiness back to the streets!

The Bicycle Bubble Machine is a bubble machine attached to the luggage rack of your bike. I actually found bicycle-mounted bubble machines on the net, but they all run on batteries, neglecting the fact that on our bikes we have a source of energy which is much more sustainable and fun: relative wind. The Bicycle Bubble Machine only uses the relative wind created by riding your bicycle: a wind wheel will turn a wheel with bubble wands, which are blown directly by the relative wind. It works surprisingly well at a comfortable range of speeds, and with the funny, jet-engine look the machines have, when one is attached to every side of your bike, it's an eyecatcher. Well, at least it gave me a lot of strange looks when using it on the street.

This is my first real project constructing something which moves. While I'm not an engineer (so please be kind!) I did put a lot of work in this (and printed lots of prototypes ...): for example the tank was supposed to be printable in one piece, store enough liquid, not store too much liquid in 'dead' places, and not spill all the time while cycling. The design now for example has bulkhead walls to reduce sloshing effects. That said: it will still get messy, but that's part of the fun :)

While I thought about a gear system, I discarded this idea, because everything I could come up with led to a) a smaller tank, b) larger dead spaces of fluid, c) too many wind turbulences in the bubble path etc. If you're interested, I've written about the process of designing this here

This thing is not difficult to build. I tried to give detailed instructions.

Future improvements might be: a lever to temporarily block the bubble wheel, so you can turn off the machine when it is not needed; and modifications to the bubble wheel like combining two bubble rings to a long one for larger bubbles, or improving the topography of the bubble rings to store more fluid.

For the pulleys, I used Parametric Pulley by droftarts. I kept them although I dropped using tooth belts (replacing it with elastic ribbon), because they give good friction.

Please take a look at these remixes:

http://www.thingiverse.com/thing:976106, http://www.thingiverse.com/thing:973210 and http://www.thingiverse.com/thing:1656828. They definitely make this design better; miroks tank prints easier and without difficult removing of support (his bubble wheel makes more bubbles and might print better on printers with problematic bed adhesion, but for you it might also lead to many connected bubbles which don't fly as good, as someone reported); 3dMODler's remix will help those with friction problems on the pulleys. The third one by jkf123 is a clever idea to reduce spilling even further, by collecting spilled liquid and leading it back to the tank again.

reparator's remix https://www.thingiverse.com/thing:3808090/ is a very impressive redesign of the whole thing, improving on many aspects at once!