32 replies to this topic

[wjames]

Hi guys - quickie here.

after gobsmacking the people who attend my yearly bonfire/fireworks last year with my firecrackers,EVERYONE who is coming this year has asked if i'll be doing the same, or something similar....

Now, noise is a integral part of fireworks for me, so i always make some ( nothing fancy, 3/4 dia tubes, 5 inch long, thick walled, Filled with Mg/Pot Nitrate 50:50), along with a small roll of micro crackers.


So, forgetting all that, i plan to make 1 ground salute to either start, or end the display. At the moment, i was planning on using a 2 4 inch shell casings - likely 1/2 filled with the above flash compostion. I favour it for being easy to mix, easy to ignite, LOUD, and ( relativly ) safe.

now, obviously taping up shell casings with flash inside : a - won't be easy, and B : won't be safe.

for that reason, i wonder if i would be safer using a plastic container - with the flash being mixed ( in small batches ) on site, 30 mins before use......Im open to suggestions, and also keen to know what the industry standard is.


Thanks in advance.

[Potassium chlorate]

When I mix more than a few grams of flash, I do it in a closed ziploc bag with antistatic spray on my hands and the bag.

If you use a small ziploc bag, you can simply put it into the shell case when the mixing is done and ignite it with a spolette or some kind of safety fuse, without opening the bag again.

[wjames]

When I mix more than a few grams of flash, I do it in a closed ziploc bag with antistatic spray on my hands and the bag.

If you use a small ziploc bag, you can simply put it into the shell case when the mixing is done and ignite it with a spolette or some kind of safety fuse, without opening the bag again.

really - even with pot. nitrate+ Mg.....I'd have thought the introduction of ANY plastics was a concern for static........then again, i remember a video of someone mixing 200g of perc/al flash in a bag.....

[helix]

If your just making one why don't you use the binary method? and just add the mg/ KNO3 unmixed, tape up the shell and then roll/ shake the contents for a couple of minutes to mix the contents.
This is probably the least dangerous way to mix it.

Edited by helix, 27 October 2010 - 09:51 PM.

[wjames]

If your just making one why don't you use the binary method? and just add the mg/ KNO3 unmixed, tape up the shell and then roll/ shake the contents for a couple of minutes to mix the contents.
This is probably the least dangerous way to mix it.

I was thinking about that too.

Seems safer than mixing 10 batches by diaper, then trying to seal a shell.

[helix]

I think that the binary method is the only way flash can be mixed at the PGI conferences in the US now and would recon it has to be the least dangerous way to go.

PS I've never tried it personally as I really have no where I could fire a ground salute that size without drawing a serious amount of unwanted attention - as it will be seriously loud.

[wjames]

i'll measure the weight needed to 1/2 fill a 4 inch shell. i guess at 50grams. 50 grams of Pot. Nitrate/MG flash confined in a taped up shell.....It'll be LOUD, but not crazy.

It'll be set of ON the ground, not in a frame. 40 second fuse, to allow safe retreat to 40 metres.

[cooperman435]

Id advise against it ON the ground as it can lift dirt and propell it at high speed everywhere, just an old rocket stick to lift it about a foot or more into the air for safety

[wjames]

Id advise against it ON the ground as it can lift dirt and propell it at high speed everywhere, just an old rocket stick to lift it about a foot or more into the air for safety

I thought about that too - wouldnt you be concerned the old rocket stick became a projectile ???

[cooperman435]

If the salute is taped to the top of it then any buts of wood are propelled downwards, if you stick it to the side then have the stick to the rear so any bits went backwards, simples!

[ExplosiveCoek]

When I mix more than a few grams of flash, I do it in a closed ziploc bag with antistatic spray on my hands and the bag.

If you use a small ziploc bag, you can simply put it into the shell case when the mixing is done and ignite it with a spolette or some kind of safety fuse, without opening the bag again.

You're crazy or what? Yeah, let's throw some flash in a baggy.. The small Al particles wont rub each other to generate static el, the plastic baggy isn't going to make it even FAR worse. DAMN

Just diaper your flash, screen it or use the binary method. Don't shake it if you use the binary method, the handling itself will mix the ingredients (poorly..).

Spherical shell casing's suck for salute, you can better make a can shell like one. And follow Cooperman's instructions on the stick .

[Atom Fireworks]

Lmao a 4" ground salute, now thats gunna be awesomly loud. Just make sure its plenty far away from your audience. I take it nitrate flashes are abit softer than perc dark ali ones? I suspect in half a 4" ball shell the amount of flash would be around 50grams, And if that was the flash i can make i would not be letting that quantity of let alone on the floor. I stick to 6 gram bangers and hell at 50 meters away they punch you in the chest.

Do be carefully with flash mate it only takes 1 accident and your hands are gone, and with the quanitity your likly to have it will damage you serverly may even kill you so be very cautious. I dont no much about nitrate flash but if its not too far away from my mix then its extremely dangerous, so much i refuse to make anymore than a 10 gram batch at any one time even then ime bricking myself with my welders gloves on, mask ear muffs and thick clothing.

Maybe you could do a video of this for us?

[RegimentalPyro]

Top Tip!

When mixing "standard" 70/30 Perc-Al flash the addition of 1% fine graphite powder reduces the mechanical sensitivity drastically, with little to no impact on the performance.

Mix the graphite in with the Perc first, and then add the Al and mix by your chosen method (diapering / ziploc etc)

It's a good cheap way to cut the risk factors down - I never mix without it personally.

[Atom Fireworks]

Top Tip!

When mixing "standard" 70/30 Perc-Al flash the addition of 1% fine graphite powder reduces the mechanical sensitivity drastically, with little to no impact on the performance.

Mix the graphite in with the Perc first, and then add the Al and mix by your chosen method (diapering / ziploc etc)

It's a good cheap way to cut the risk factors down - I never mix without it personally.

Could you elaborate on this, how exactly does it reduce the risk and so forth as i dont really understand the chemistry of it all. Also i dont use the standard 70/30 mix i use 2/1 ratio little different to the 70/30 but will the graphite still work?

Anything to reduce risk mate as ime petrified of the stuff.

[RegimentalPyro]

It's not a chemical action - It works by reducing the friction risk. Graphite powder is a very good lubricant - It's often used in locks.

The reason it acts as a lubricant is that graphite is made up of sheets of carbon atoms arranged in layers (NB a single sheet of carbon atoms is known as "graphene"). The bonds between the layers are very weak and thus can easily slide over each other.

You can experiment yourself with this. Take a softish pencil and use it to completly shade in an area on a sheet of paper. Now take your finger and rub it over the shaded part. You should find it much smoother than the unshaded paper. (pencil "lead" is basically graphite, with some binders)

Add to this the fact that graphite conducts electricity and you have something that not only reduces mechanical sensitivity but also cuts down on the static risk

Neat huh?

Edited by RegimentalPyro, 28 October 2010 - 01:50 PM.