My daft uncle taught me this: fill a balloon with natural gas. Tie it off with a long polyester knitting yarn. Light the end and let it go. It will float up into the night sky with flaming drops falling from it rather prettily. Eventually, the yarn burns to the balloon, igniting it in a silent swirling ball of fire. This makes a very satisfactory spectacle, resulting in many calls to the authorities.

Lift is dependent upon the makeup of the local gas (pure methane is OK, while in some areas, there is too much ethane and propane, and in still others, hydrogen provides extra lift). But, if you don’t get enough lift, there is a danger of your mini Hindenburg blowing sideways into your neighbor's dead pine tree, and setting that off in a spectacular blaze. If this should happen, retreat indoors until firemen arrive. Then, in housecoat and slippers, answer any probing questions with mysterious references to “ball lightning”.

For those areas without satisfactory natural gas, Pluterday has designed a water electrolysis unit that fills a small bag with hydrogen – or a mixture of hydrogen and oxygen, if you want some noise.

Pluterday has enlisted her husband to launch the first ever H2/O2 bag.

<looking out the window with fingers in ears...>


(manufactured mostly of my recycled annos...)
-- pluterday, Feb 06 2003

(?) Actually pluterday, 6 idiots were killed by 1 device http://216.239.51.1...ar+2&hl=en&ie=UTF-8
[thumbwax, Oct 05 2004]

Isn't natural gas heavier than air? Visions of playing a disastrous hybrid of "hot potato" and soccer.
-- sild, Feb 06 2003


We used to do this with butane from disposable lighters. That makes it double-Baked.
-- phoenix, Feb 06 2003


Methane (the main component of natural gas) has a molecular weight of approximately 16 against molecular nitrogen at 28 and oxygen at 32 (making air about 29 on average). But there is the weight of the balloon to consider.
-- kropotkin, Feb 06 2003


[blissmiss] Yes, this was "not" your drug experimentaion phase, and yes, those were "not" polyester knitting yarns attached to that coat hanger!
-- pluterday, Feb 06 2003


We used to twist together the four corners of a sheet of a large newspaper, light the twist and watch the hot air "balloon" float away to the neighbors. That was when we weren't arranging spray cans for launch in our trash burn barrel.
-- FarmerJohn, Feb 07 2003


[FarmerJohn] //launch in our trash burn barrel//

Ah, those were the days, weren’t they. Kids could do anything. My parents gave me matches to play with. But I was envious of my brothers, who walked around the yard with their real rifles, shooting everything in sight. And this was the suburbs! Now, to grow up in such an enriching environment, it’d have to be the inner city.
-- pluterday, Feb 07 2003


Especially when camping. Once a few of us put some water into an empty treacle tin, hammered the lid shut with a mallet and set it on a primus. After a couple of minutes the lid blew off with a huge bang. We looked around and couldn't see it anywhere. Just as we'd given up seeing it again, thinking it must have landed in the bushes or something, it hammered into the ground about six inches from the stove, destroying itself in the process. No pyrotechnics, but the thought of what might have happened if one of us had been sitting in the wrong spot frightened us witless.
-- egbert, Feb 08 2003


I've never done it but you can take a dry cleaning bag, or something similar, and construct a frame so that you can put candles underneath the opening. If its hot enough it will heat the air inside the bag and float away. Looks pretty cool in the dark if you don't know what it is. I'm sure this could be rigged to blow up. If not, it is still bound to crash in a fiery inferno of burning plastic.
-- notme, Feb 08 2003


[notme] The Japanese actually did something similar during WWII, launching balloons from Japan timed to drop bombs on the US mainland. With a lot of effort, they managed to kill one person at a picnic, and to set a number of small brush fires...
-- pluterday, Feb 08 2003


When you do this with Butane, the balloon drops like a rock. Sometimes if you're unlucky/stupid and directly light the balloon indoors with a lighter, you burn off all the fine body hair on the right side of your body and have a crazy story to tell later.
-- cameron, Feb 08 2003


Woah, you are all way off, I have somewhat perfected this technique behind my mums greenhouse, and its actually quite simple. Basically get some sodium hydroxide (caustic soda) crystals, a fair bit of aluminium foil, a wine bottle and a balloon. Make some pretty concentrated NaOH solution and put it into the wine bottle, put the aluminium in the wine bottle and then stick the balloon on the neck of the bottle. The reaction starts off pretty slow but once it gets going it only takes a few more seconds and you get enough hydrogen produced for about one and a half balloons. Then the rest sorts its self out, tie the balloon and add some sort of detonator, I used string soaked in white spirit. It floats up, there is a big white flash and a loud boom. When I said I perfected it, there are a few things to consider, basically the reaction is exothermic and the reason why it starts of slow then gets a lot quicker is cause its cold to start off with, and then it gets VERY hot, which is why I say ‘use a glass bottle’, the first time I did it, I did it in a fruit cordial bottle, when it got hot it shrunk squirting hot caustic soda over my hands, not nice, I was wearing gloves but I got a couple of bad burns to my wrists. Another thing, cause it gets hot you get a lot of steam in the balloon, so I developed a way of condensing the steam to water using a separate bottle of cold water and a bit of siphon tubing.
-- STE_2020, Feb 08 2003


The best way to do this is a netural mix of Oxy-Acetaline from a cutting torch. Just get a neteral flame going and put it out against the floor wile leaving the gas running. After tht tip cools, fill baloons.

I have has a lot of fun with these. They will alert everyone with a mile of you. They are quite dangerouse though..
-- dlapham, Aug 11 2004


I have been thinking much more about the hydrogen wine bottle generator than is right. I have been trying to figure out the chemistry. Is it this? H20 + NaOH + Al2 -> H2 + AlOH + NaOH?

Does the Na ion regenerate more OH by stripping it away from water? Or is the product aluminum oxide? Chemistry help, please.
-- bungston, Mar 30 2005


[bungston] Can't remember the chemistry - your reaction doesn't quite look right -, but the caustic soda/aluminium foil method certainly works. We used a champagne bottle cooled in a bucket of ice water. Collected a cluster of about a half-dozen balloons, attached a long saltpetre and string fuse, lit it and let if drift off. Must've been at about 600feet and a half mile downwind when the late evening light was augmented by a bright curl of flame, and a couple of seconds later a satisfying "boom". <sigh>
Don't try this at home, kids, even with a grown-up in attendence.
-- TolpuddleSartre, Mar 30 2005


I'm giving this entire idea a bun because it's the first idea where I've come across <TolpuddleSartre> easily the best u-name on the site. And the idea is pretty nifty too. [+]
-- etherman, Mar 30 2005


Heh. Glad to see the pyromaniac parts of the bakery are still intact, as always. When I was at camp, I managed to find a way of making all used loo paper to light up and fly away... All the boys wanted to know how I did it, but I had to stop after I was nearly caught by the teacher... Of course, I showed them, and the next day, John was in deep trouble for setting fire to a bush.
-- froglet, Mar 30 2005


Toilet paper? How old are you [froglet] ? Toilet paper is like, *so* primary school. (Unless, of course, it was ignited with some homemade mercury fulminate, or ammonium tri-iodide).
Bun, if video of H2/O2 balloon is made available.
-- AbsintheWithoutLeave, Mar 31 2005



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