Water Rocket and launch platform (Complete instructions)

https://youtu.be/JNP6PwhbNHg

Update 2021-01-31

As a small boy (a long time ago) I had a water rocket toy.
I decided to build one for my grandchildren. The base idea that the toy will be (relatively) safe so that young children can play with it. I do not have the ambition to set height records etc.

After looking around on Thingiverse and in the internet, I found designs based on the Gardena garden hose coupler.
My design is based on this Gardena coupling and on a 0.5 or 1.5 litre PET mineral water bottle.

The launcher is "universal" and can be used with different sized soda bottles.

The idea is the the air pressure pushes out water in the rocket so providing upward thrust.
The rocket is designed that it should stay vertically as much as possible, even at the top of the flight path, and fall down with the fins down (depending on the launch angle).
When falling down, the cone should come off and deploy the parachute.

So far this design is "works in progress".


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