Not long ago I was challenged to create a project using a water bottle that could be displayed in a one minute long video. While I missed the one minute mark, I think I still managed to make a pretty entertaining device.
The rocket and launcher featured in the above video function off of a very simple concept of igniting a flammable vapor using a replacement barbecue igniter to propel the bottle through the air. The parts for this project should cost no more than $15, with the igniter taking up the majority of that price tag at about $10. The bottles can be reused many times until the heat from repeated shots eventually warps the plastic.
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