A couple of weeks ago, Naomi saw a water rocket on TV and requested that we make one. It's a pretty simple affair - a juice bottle which you put a little water in, then a stopped, then some compressed air from a bike pump. When the pressure gets high enough, the stopper pops out, water and air shoot out the bottom, and it takes off. Last weekend, we gave it a go, but given a lack of essential resources, the result didn't look great...
Rather than a stopper, I used some bubble wrap, and for legs we had part of a Graze box. The bottle also had quite a wide neck so the water didn't come out in much of a jet. It only managed to make it about 2 foot into the air, though Naomi was still quite excited by it.
Last week, I kept an eye out for more stuff. First I found a better bottle, and I realised that one of the stoppers that came free with some calpol (for filling a syringe from the bottle) was quite a tight fit. Perfect!
I drilled out the stopper a little some my tubing fitted into it tightly. The tube is some I had lying around - B+Q have it for a pound or two per metre.
Add some gardening sticks from a 99p shop for legs, and some decorative stickers, and we have a better rocket:
Here it is ready to go...
I thought it would still only make a height of a few feet, so we launched it in our garden. Here's Naomi working the bike pump:
Alas, I didn't get a video of the launch - but most impressively it managed about twice the height of our house! It managed to go straight up and down, landing on our whirligig (for which Naomi felt compelled to say sorry to mummy several times). Anyway, it was so successful that I'm not all that confident at getting it to land in our garden again, so at some point we'll go to the park for another go.
Meanwhile, this was a well recommended way to spend an hour on a Saturday. Very fun!