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Flash. [17 May 2004|04:20pm]

aznsk8erboi
Any bang heard from a pyrotechnic device is quite likely the result of flash powder. The m-80s and cherry bombs of ages back, now federally banned, were filled to the brim with this fine gray mix. Simpler than blackpowder, it's most often an unprocessed mixture of potassium perchlorate and aluminum powder in modern application. Even in small quantities and in light confinement, it is devilishly loud.

I favor the 70/30 flash mix; 70% Potassium perchlorate, 30% german dark aluminum. Supposedly sound tests have proven it the loudest, in a chest-thump, ground-shaking sort of way. For a crackier report, delightfully-toxic antimony sulfide is sometimes added. The original m-80 flash comp achieved it's cracking boom in this way.

For small amounts, 10 grams or less, I'll again use the plastic baggie method for mixing. 10 grams is still enough to rip off a forearm, and may, depending on it's proximity to important flesh, prove lethal. A 10 gram salute is roughly equivalent to the standard quarter-stick. Some will tape the mixing bag to a pole, others will simply mix it carefully at an arm's length. It's vicious stuff. A spritz of static guard will eliminate the small chance of ignition from a static spark, however unlikely that may be. Perc/al flash is pretty stable, and not practically friction sensitive. Still, just swish it around at the bottom, don't spastically shake it.

The safer method of mixing invovles placing the two unmixed chemicals onto a sheet of newspaper, then gently rolling them into each other by lifting each side of the paper. This is the diaper method. It cuts down on friction, but does take a while. Very fine chemicals have a tendency to spill around, so it also takes some practice. If you're doing a large amount of flash, this is the way to go.

While it's all reasonably safe when done properly, do keep batches under 100 grams and do start small. On a crap scale that doesn't show milligrams (Walmart stock), most people will mix up 10 gram minimum batches. It appears to be a very small amount, and it's easy to forget just how powerful that mundane gray powder is.

The safest place to store flash powder is within completed salutes. It's easy enough to make fresh when needed, so there's no need to stockpile. And, of course, unlicensed manufacturing of flash powder is a federal felony within the United States. Keep it small, and use immediately what you make. If you live in a neighborhood with cranky elderly people, wait until a thunderstorm to set off your salutes.
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Chlorates and Sulfur, Oh My. [17 May 2004|02:48pm]

aznsk8erboi
Our good friend, Tom Peregrin, author of Introductory Practical Pyrotechnics, will scream himself retarded declaring the hazards of chlorate/sulfur mixes. As will most internet pyrotechnics enthusiasts. And well they should, because these mixes are dangerously sensitive, and usually unneccesary. However.

Testing in small amounts is fairly safe, and gives certain insight that would otherwise be lacking. One should never trust completely internet authorities, as they often dramatize matters to protect the death-prone simpletons that may be reading. So then, a sample is prepared.

Technical grade, fine sieved potassium chlorate, and equally decent sulfur flour. A gram or less will work, swished lightly in the bottom of a waxed paper cup. The fine powders will splash around some before the desired consistency is acquired. It doesn't have to be perfect. When done, get a steel hammer.

Pour out a small mound onto asphalt, outdoors. Start small. Now, extending your arm out as far as possible, give the mound a quick whack, just like hammering in a nail. Chances are nothing happens. Give it another, and another. Continue. Eventually, one of these strikes will do it.

This mixture roars. The report is something like a defeaning pop. Loud enough to give one ringing ears and light shell shock. When this initially gave, I was quite surprised, to say the least. The hammer head did not fly off into my skull, and I must say I was a tad disappointed at that. This mixture is flamable, but the smacked mounds did not seem to flame up in a noticable way.

This is of course entirely empirical. Stored a few months, using poor grade acidic sulfur, the resulting mix may have been far more sensitive. Proven in this particular test was, simply, that this mixture is indeed unstable, but not that unstable when quality chemicals are used. There are many star comps that require chlorate/sulfur mixes, and to be honest, I'd feel okay using them. A proper respect is needed, but overpowering fear is not.
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Blackpowder: A Quick Peek [17 May 2004|02:04pm]

aznsk8erboi
Potassium nitrate, charcoal, and sulfur. Mix them up in the correct proportions, and the result is blackpowder. A very, very slow burning blackpowder, often referred to as 'greenmix'. From a pyrotechnics point of view, greenmix is pretty useless without further processing. It is, however, incredibly quick and simple to mix up. For blackmatch fuse, primes (slurried blackpowder coating a difficult to ignite comp) or heavy walled salutes, it is passable.

I generally use a plastic bag to do the initial mix. Weigh out the chemicals on a digital scale, pour them into the bag, zip closed, then shake until it looks consistent. For a burn test, you can just stick a length of fuse into a small unzipped opening, rather than wasting a good tube. Keeping in mind, of course, that melted plastic glues itself to most surfaces. Including your skin.

The classic proportions for blackpowder -- Potassium Nitrate 75%, Charcoal 15%, and Sulfur %10. Pick up your chemicals from a legitimate supplier, and give it a crack. It's one of the safer pyrotechnics projects for a beginner.
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Monster Pyro: Nuclear Bomb Simulators [08 Feb 2004|10:48am]

aznsk8erboi
"The most ambitious and also least innocuous training devices are the ones which are meant to simulate an atomic bomb. The EX1 Mod 0 Nuclear Air-Burst Simulator is an air-launched bomb weighing in excess of 500 lb and containing various flash, smoke and sound charges. With a total of 300 lb of a modified magnesium flare mixture, red phosphorus, and high explosive, it produces an impressive fireball and "mushroom cloud."

- Military and Civilian Pyrotechnics, by Herbert Ellern
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Non-Technical Crap [05 Feb 2004|04:47am]

acemcgaven
To all of you intimidated by my partner's technical aptitude, I am here, repreZenting for the inept crowd. I can't tell my C4 from my Semtex, but I have one or two burning and explosion stories. Sadly, only a very limited number are suitable for the public domain.

Today, I speak of a movie. It wasn't a good movie, or even an expensive movie. It was, in fact, a piece of shit. The budget was $4000 Australian dollars, and the crew were all working for free. Half the budget went on this one scene. Oh, the day was memorable.

The cast and crew drove into the middle of fucking no where, to the countryside abode of Mad Bob, the armorer. Mad Bob was an insane Vietnam vet who owned an enormous collection of firearms and about a ton of explosives. He was allowed all this because he supplied films with props.

He and I got on and ended up doing a bit of shooting later on, but that's another, less interesting story. On this particular day, we had one purpose in mind. We were going to blow up a car.

The scene was set. We filmed everything involving the car before it went to its grave, set the scene, then Mad Bob came in and packed the car with explosives. A consumate professional, he had the thing ready to pop in under fifteen minutes.

The cast, crew, director and I stood a safe distance back and watched with rapt attention as Mad Bob allowed a pretty young girl to push the plunger on the explosives.

When the old heap of junk erupted into a massive fucking ball of flame, two things became suddenly apparent. The 50 or so meters we had stood back was not, technically a safe distance. In fact, mere seconds after the explosion, debris began to rain down on top of us. The trunk's lid fell about a foot away from the director with an audible 'SHUNK" sound.

The second, and slightly more pressing point was that the director was a fucking moron, and had neglected to siphon the gas from the car's tank. Burning gasoline surrounded the flaming wreck. In the middle of a field. Of long grass. In summer. In Australia.

Does anyone see the recipe for fun here? It gets better. Part of the explosive hadn't detonated for some reason. It was likely a dud, but there was always a chance that it could go at any minute. A second explosion would send flying wads of fire across the field, and guarantee an almost instant brush fire that could grow to massive proportions.

Thankfully, Mad Bob lived up to his name and leapt at the potentially suicidal mess with enough guts to provide ten million sausage skins, and a huge foam-firming fire extinguisher. The day was saved. Ah, I miss Mad Bob. That crazy redneck motherfucker.
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Visco Followup [04 Feb 2004|07:19am]

aznsk8erboi
Browsing the previously linked cannonfire website, I couldn't help but notice the curious nature of their product offerings. They have the fuse, as mentioned. They also have conveniently sized red tubes, with matching endplugs. That's about it. Interesting.

Order placed.
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Real Men Buy Visco By The Ton [04 Feb 2004|03:16am]

aznsk8erboi
With 5000 feet of the green stuff, waterproof Visco, you can live off the rest of your life without need or want for high quality fuse. To put that in unneeded perspective, a mile is 5280 feet. Being smart, you would of course purchase that remaining 280 feet for bragging purposes. What you'll actually do with that fuse is another question entirely. You could be trite, and build some sort of fuse-lit thermo-nuclear device. But that's been done to death. Secretly, and in Pakistan. Alternatively, you can just keep yourself in fuse until the day you die (that might not be saying much). On average, a non-shell pyro device will use about three inches of fuse. 5000 feet is equivalent to 60,000 inches. So math fans, that's enough for 20,000 average devices. More if you skimp, which you shouldn't. Finally, you can take the mundane way out. Travel a well-established path by reselling sections of your monster load. From a 5000 foot spool, you can sell 50 lengths of 100. At $18 each, that's $900 total (before subtracting ~$450 fuse cost). Total work for you -- cutting and shipping. It's a good business if you can get into it. Good luck with that.

There are multiple suppliers on the net that will ship in this quantity, and the price tends to be in the $450-500 range. What's truly disturbing is, they must be making a profit. How much do you suppose they're buying it for themselves?
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Fireworks Accident #5 [04 Feb 2004|12:34am]

aznsk8erboi
I've never caught myself on fire, and thank the goodness for this accomplishment. Sure, like every other sane person in this world, I've tapped a butane refill cylinder into my jeans, then lit afire the cold spill. Up shoots a dandy jet of sustained flame, and quickly begins warming the leg. Practice self-immolation. This seems like it should be dangerous, and with anything but blue jeans, it probably is. But, I never have let it go far enough to burn surrounding areas, which would inevitably lead to my tragic death. Though fire has never consumed me, I have burned myself. Oh how I've burned myself.

Like all good fireworks accident stories, this one happened in the Summer. The day after Pyro Holiday. July 5th, and there I was, looking 17, with fireworks leftover from the previous night. It's sacrilege to store them, so I trekked out at dark, flammable toys in-tote, to the zero-visibility backyard. No bottle rockets, no buzzbombs, not even a salute. These were strictly fountains and single-shot aerial pieces. Pretty.

Given that my former-backyard was grassy, and a little bumpy, it could not be used. Something level and non-flammable was needed. I settled on an empty metal can that had previously been used for gift popcorn or some such. It had made it's way into the garage, and it was about the right size and weight. In went some cat litter, and with that, I was ready to begin lighting up the sky. Which I did, and oh how fun that was. Fun in an "oh God I hope nothing catches on fire and the police don't come and arrest me" sort of way (nothing did, and they didn't). Fump pop pap. One after the other, jogging around in the dark. The low-hanging clouds of smoke smelled of sausage and weed killer, and I breathed it in deeply.

Now for the burn. Quite content with myself, and throughly unexpecting a gastly accident, I began cleaning up. The still warm cardboard mortars found a home in the trash, along with the little scattered pieces they had shot out. I was neat and tidy, and it showed. The backyard look fantastic, though I could not see it. What an excellent night this had been. I love fireworks. So let me just pick up this can right here and go inside. With my full hand too, because we wouldn't want to drop it.

Dear reader, this can was no longer a popcorn can, it was a hot can. Hotter than the devil's morning coffee. My frail skin quickly fried and the can fell. I did not cry out, being a tough man and all, I just looked confused and pained. I couldn't see the hand, but I knew there were burns. I could not run inside fast enough. The hand, the hand was dying, and it felt it. Throbbing and burning, and the stinging too. There was a pain party, and everyone had been invited to rock out. All the while, I could not help think. That Dirty Fucking Can. After I patched myself up, I would kick that can as hard as possible into the wood. Stomp on it, really teach it who the boss man is, you know?

But for now, I concerned myself with my wounds. The bathroom light revealed three separate burns. They weren't horrible, but they looked and felt like a problem. I had heard of remedy for burn pain from my grandmother years before. Essentially, you start by rubbing salt into it the burn, then finish with a sandpaper and lemon juice rubdown. She's a crazy bitch, so I instead just kept my arm submerged in a bowl of water for several hours. Little spots and splashed of it got all over. Not so much fun, no.

Years later, though I can barely see the scars, I still hate that fucking uppity can.
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Light It And Run, Get Back! [04 Feb 2004|12:20am]

aznsk8erboi
Epoch messages are largely irrelevant. Do know this, however. I am your lord and commander here. They call me Kevin. But truly, that is not my real name. My real name is Steven, but you may not call me that. Aznsk8erboi, or nothing at all.

Now, already-joined-screwy-pyro-types, let us post various pyrotechnics interests for the benefit of future readers. It will be good. There will be standing ovations and showered gifts. I will go first.
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