37 replies to this topic

[blur]

I constructed a small firecracker within a 1 1/2" tube yesterday with paper glued on both open ends for "caps." Wren ignited (fuse coming from a hole in the middle of tube) there was no explosion like a normal firecracker. The paper caps simply broke open and fire flew out of the sides... any ideas why?

ps: the contents was made out of numerous small firecrackers broken open and emptied.

Thanks.

[BigBang]

Oh dear, another one that doesnt value his fingers Its obvious to me, by asking that question, that you dont know the first thing about pyro, so im not going to begin to answer your question. But i will warn you to stop what you are doing because by doing things you dont understand, you will have an accident.

Stop taking apart ready made fireworks, and start reading a few books and this forum. Learn the basics before attempting to make even the most basic of fireworks. You certainly shouldnt be making firecrackers at this stage.

This is very good advise - Take it!

[portfire]

First,dismantling fireworks is really NOT a good idea as you dont know whats inside.If you search the forum you'll find that people here dont like firecrackers (i think there boring personally).

start with BP/ small fountains first there relatively easy and alot more interesting than firecrackers



regards
dean

Edited by portfire, 23 March 2007 - 03:23 PM.

[blur]

I appreciate all the sympathy for my health, but do you guys know the answer to my question? lol
Although i will take your advice and read up some threads on these forums

[blur]

i kept experimenting and could at best get a loud puff.. oh well, i give up.

[ProfHawking]

There is no need to give up, just learn some more about what you have there.

The reason your gadget didn't work should be easy to work out once you have learnt a bit about how fireworks work, like confinement and burn rate. The contents of commercial fireworks can be surprising and dangerous sometimes, as you don't know what they are until you have lit them.

Read up on some things. Have you looked at Passfire.com? Then maybe try making your own black powder perhaps, and work up from there, pressing it into a tube to make a fountain or something.
You then know what's in it, and have a more educated guess as to what it will do.

[blur]

I know of many combnation mixtures to form black powder of sorts, although im not sure where i can purchase them. The only possibilities i could think of (other than online which i would like to avoid) is home hardware or something. I live in a small town so it's hard to get potassium perchlorate, etc. Yesterday my detonations where nothing but puffs and sizzles, the air would always escape out of the slightest hole, and if there wasnt one, it would break through the weakest area. I would guess for an explosion you would need no air to escape through one direct location but instead exert equal force upon the entire casing, causing the explosion.

[StevenRS]

What i think is happening to you is that when you break the firecracker open to get the silvery-gray flash powder, and poring it out, you are also mixing in some of the red or white inert plug, causing it to burn slower. Do be careful though, flash powder is pretty powerful stuff.

[Zinginex]

I would guess for an explosion you would need no air to escape through one direct location but instead exert equal force upon the entire casing, causing the explosion.

In my experience if the end plug is strong enough and a lot of pressure is needed to burst it out you would still get a report. Obviously not as loud as a entire destruction of the casing but for that i'm geussing you need good flash powder. Black powder normally just will pop out of the weakest spot in the casing.

[paul]

Black powder normally just will pop out of the weakest spot in the casing.

Flash does the same but due to its high velocity turn the whole casing into "a weak part". Its definately not true that black powdern does only pop out the weakest spots in a tube or whatever.

If you take good black powder, use proper end plugs glued in with white glue, even the strongest cardboard tubes "explode" into pieces

[blur]

thanks for the input guys.
and to address Steven's comment, i actually did do that the first time i tried lol. The clay and plug was mixing into the flash powder and there was no iginition at all lol

[king pyro]

Oh blur sorry that I am late. Though its a bit dangerous but I did the same thing when I did not have acces to much chemicals so I will tell you the answer which common sense says. I am not too good at all those confinement and burn rate but common sense just says that either there are impurities making it burn slow or either the tubing is too strong. Just use some better explosive(either made at home or emptied from firecrackers) and use a weaker tubing. Fill almost 2/3 of the tubing and use enough glue to ensure that those paper bits(used as caps) are properly fixed. Make a good fuse(I prefer using a long quickmatch) so that you dont have to make a big hole for it. These are just basics and dont need much knowledge about pyrotechnics.

Hope this helps. And let me remind you, this is common sense.

[Mumbles]

I wouldn't listen to king pyro. He doesn't seem a great deal more experienced than you, so it would just be the blind leading the blind. Just wanted to make you notice he is advocating the complete opposite of what the respected members above are recomending.

Anyone primarily making ground salutes to me has no place in pyro to begin with. However anyone advocating leeching flash powder from fire crackers, and then igniting it with quickmatch is just waiting for Darwinism to catch up with him.

[karlfoxman]

Well said Mumbles, Kingpyro please understand the terms we use in pyrotechnics. We dont advise taking firecrackers or any oether form of pyrotechnic device apart, if you did'nt make it then you dont know whats inside! Ground salutes are the most boring form of pyro and a doddle to make. Anyone can stick a load of powder in a tube and light it. Also, quickmatch is QUICK. If you gave me a firecracker with quickmatch as the fuse I would not throw it or light it. It will go off a few hundreds of a second after you light it!

And saying you dont need much knowlage about pyrotechnics makes me laugh, as you dont have alot of knowlage and dont know the basic terms.

Ok, I suggest you do some serious reading on pyrotechnics before advising members on dodgy procedures.

Just my 2 pence

[TCblastmaster]

King pyro, try making something aesthetically pleasing - it's far more challenging and you also get to keep your fingers! I think that 'common sense' may have deserted you.

Seriously though, unknown compositions extracted from fireworks when mixed with others may react violently and without provocation- e.g. sulphur and chlorate, etc. Mix two compsositions together you have a new comp. of unknown characteristics or sensitivity.

Whilst I would feel happy to handle a Kilo of BP, I would not relish doing so with 10g of another.

Be careful.