I have been playing with water-rockets for about 6 months after buying my 5yr old son a "Full Bore" water rocket launcher kit for his birthday: http://www.rocket-fun.com/Product.html I bought the standard version. I have to say the launcher is excellent and safe to 120psi (tested) which is more than enough for our rockets at this stage. I will admit here that the launcher was a bit of a "Homer present" to say the least! I got interested after stumbling across some AirCommand videos on youtube.
Anyway, here are some pics.
1. http://imageshack.us/a/img819/9960/imag0717d.jpg Our first rocket. Inspired by my son with reluctant bouncy ball astronaut strapped in the nose cone. Launched at 40psi flew very straight indeed and survived several hard landings:
2. http://imageshack.us/a/img845/4249/imag0755a.jpg Second rocket. Again flew high and straight - survived several landings at 60psi but was bent to bits after a 100psi launch.
3. http://imageshack.us/a/img833/5981/imag0988ty.jpg Getting a bit more serious here. On the right is my rebuilt 2l rocket using the corriflute fins from our first rocket. On the left is my first attempt at something more serious. It is a 6l rocket coupled with 2 robinson couplings using brass lamp rod and fittings. The pic shows the nose cone which was intended to so simply fall off as the rocket tipped over at apogee and release the chute. However, although the chute deployed ok, it always deployed far too early and brought the rocket's climb to a very abrupt end. It was not too hard to build and I knew the fittings could always be resused so in the end I just taped the nose cone on, launched it at 120psi (1.5l of water) and let it destroy itself. I was very impressed with its height, its true flight and also of course its speed as it hit the ground!

I actually launched the big rocket for the first time whilst away with a group of friends for the weekend - 18 adults and children in a huge rented house. Everyone built their own rockets at home with their children and brought them along. We had a great time and destroyed them all!! The kids (aged 2 to 6) had a fabulous time, as did the adults.

I have built a new 6l rocket but am waiting for the parachute parts (launchpad and servo etc) before I try again - probably try something similar to the side deploy system I saw demoed by AirCommand on Youtube. I will test on my 2l rocket this time though! As soon as I have a working chute system I will then be able to finally work out how much water I need for a robinson coupled full-bore rocket as I suspect it is not as simple as the 1/3 rule due to the restricted air flow. I will also try going to an 8l rocket with 2l of water and see how that goes. 7
Anyway, hi to all. Sorry for going on a bit. I will post my further updates in the relevant forum.
Great forum btw. There are clearly some very helpful and polite people on here and this is always a sign of a good forum.
