Been going through photos from old blog I had going when the kid was younger.

Been going through photos from old blog I had going when the kid was younger. One from our water rocket days where it looks like the rocket left a ghost of itself behind. Maybe it was the inner pressure chamber (another soda bottle). The second photo shows the outer bottle with all of the aerodynamics.
#WaterRockets #Kids

@jerzone a friend of mine made rockets like this, but a little differently. He glued a 1/2" garden hose spigot to the cap. Then he used zippties placed around the neck so the lock part rested on a flange of the bottle. A ring around the zipties kept them in place keeping the bottle secure while pumping. Water in the bottle and a tower bike pump with a gauge. A couple of bars of pressure and slipping the ring downwards was enough to make the bottle almost disappear in the sky. Or maybe he just used the garden hose quick release, can't remember. It was a stag party 20 years ago so the memory has faded a lot.

@harald We had a few designs over the years, started off making them with co-worker before the kid was born. Great problem solving platform, cheap/easy to get pressure vessels.