Soda Bottle rocket taken to the next level!

[Mark]

Steve,
For the love of simplicity, buy a piezo gas grill sparker and hook a twin speaker wire to it. It's so much more fun to launch from a distance. You merely have to insert the twin wire into the bottle any distance you like.
Those up close launches are too "close."
If you just cut the wire with a pair of dikes/dykes and even this meager distance between wires is plenty, just as if you were cutting a ribbon in half, it's that simple. Impress your friends! I like speaker wire because it is a little bit thinner than an ordinary cheapy extension cord. Imagine standing well back of the launch and not having to use the butane cigarette lighter on high. Click and away she goes instantly.
It's funny how a taped connection doesn't hold too well, I did the same thing with coffee cans and got a really loud bang too! And on other occasions I thought I was strong enough to hold a section down with one hand while lighting the joined vessel with the other. It's amazing how much force is developed.
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[JW]

I experimented with air/water rockets too...
I started with a bicicle pump and a simple bottle and a cork, but soon I used a old refrigirator compressor and some hoses and a much tighter cork. I experimented with lots of nozzle diameters and pressures, adding soap to the water etc, lots of fun..
Now I have a big (1500W) compressor from a old air conditioning (so big that the lights dim when I turn it on :D ), that thing is unstoppable.
Once I fired a pet bottle with it (just turn on the compressor in and run away) and it went sooo high and far, it almost crashed into a greenhouse nearby 8) .
Some time ago I had some 5 liter beer cans lying around and decided to launch them, they went pretty high, but too dangarous to fire such a big steel thing. here's a picture of such a big 5 liter beer can, its a bit mnore than 5 liter after launching it :P

[John Werner]

Here is something that you boys might like to try with the pop bottle.[/img]

[Zippiot]

i had a few bad calls with those things...

i used 2 fuels when i shot them off, hydrogen and nirtomethane....

both burn clear, hot and quick.

one time the hydrogen blew the bottle to shreds with my face just an arms lenght away...i am honestly deaf in my left ear cause of it!!!

but the nitromethane was a whole different story, we sprayed in the nitromethane and lit it, but nuthin...so we unscrewed the cap (we used the cap as the nose and drilled a hole in the bottom for the nozzle) as soon as i did i guess i breathed out, the nitromethane combusted and shot down my throat, my lungs temporaily collapsed (like 20-30 secs) we went to the hospital and the doc said my body recated to an overdose of carbon monoxide...

besides that fun stuff!!

we had a 4 inch pvc connector, and would launch them vertically. they go up about 30 feet or so with nitromethane, but this is a no seal environment, just a hole drileld in the bottom of the bottle