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Kno3/Al/S Flash Powder Storage Stability?


PyroTop

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Yes guys i know I'm a new member on here and i know the majority of you don't like discussing flash with new members. But I'm far from new to the hobby.

 

Started out making fountains, then onto small film canister shells, eventually leading up to 4" shells.

 

I love film canister shells. I don't know what it is about film canister shells just something does it for me.

 

Achieving a good break on them with certain stars that i want a hard break on seems next to impossible with BP. The small size and material that the caps are made from really make it difficult to give a hard break.

 

I would like to make some flash powder to use as break charges instead of BP. But I've never made it before.

 

Potassium Perchlorate is unavailable in my country so I'm looking to make it with KNO3, Aluminium and Sulfur. I also hear this composition is less sensitive to static discharge and friction?

 

My concern is with storage. I like to make my fireworks gradually over the year and launch them all at one time. Is KNO3/al/s a stable flash composition for long term storage? Not going to be storing the actual flash powder but would like my shells and rockets to be able to be stored for up to a year.

 

Thanks ! :)

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TP, we call that "slow Flash" here in the states. I know of no issues with this booster, Al oxidizes immediately upon exposure to oxygen so the perc doesn't attack it.

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I wonder about the slow flash too. I have an aluminum scoop that I've left partially submerged in potassium nitrate in a drum. Upon careful examination, I noticed some areas of corrosion in the form of pitting. All areas of corrosion were where the scoop was below the surface of the nitrate.

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I wonder about the slow flash too. I have an aluminum scoop that I've left partially submerged in potassium nitrate in a drum. Upon careful examination, I noticed some areas of corrosion in the form of pitting. All areas of corrosion were where the scoop was below the surface of the nitrate.

 

This is what really concerns me.

 

I also hear Sulfur + Aluminium decompose/react when in the presence of moisture. So looking at it logically, if a 2" shell was made with KNo3/AL/S as the break charge and a little water landed on the shell, would it likely ignite? We do have high humidity over here :(

 

If i have 50 homemade aerial shells and they decide to randomly ignite after a few months of storage i would be in huge trouble. My main goal here is to make a stable flash composition with readily available supplies.

 

I'm hearing barium sulfate/al/s is another less common flash composition that is extremely stable?

 

Although I've heard the KNo3/Aluminium/Sulfur slow flash composition is readily used in European fireworks. You would think this indicates some level of stability?

 

So many variables to consider. Its driving me crazy lol, after days of research I'm still just as clueless!

 

Advice is really appreciated from anyone who knows more about this than i do.

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I wouldn't assume this mixture is less sensitive to static and friction or impact. If I had to venture a guess, I'd expect it to be more sensitive due to the sulfur. I'm not trying to scare you, just trying to instill a determination to be safe and treat it with respect. It's still well within the realm of safe to use.

 

I haven't heard any reports of this mix gradually degrading or decreasing in performance over time. Generally speaking, a shell is fairly well sealed up and should be fairly stable.

 

I haven't heard of sulfur and aluminum reacting in the presence of moisture, but nitrate certainly can. I think justvisiting's experience with his scoop shows this. It's also fairly common in glitter stars. Read up on this if you want to learn a little more. Glitter stars are often kind of the perfect storm of conditions to make this happen, and it's extremely rare an ignition ever happens. If you want some added stability, or at least peace of mind, I'd suggest adding a couple percent boric acid. I wouldn't be too worried though overall. Once sealed a shell shouldn't be absorbing or allowing much water in even in the event of an accidental spill, leak, etc. If enough water is present to penetrate a shell, I'd think there is also plenty enough to thoroughly soak it to the core and render it inert.

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I wouldn't assume this mixture is less sensitive to static and friction or impact. If I had to venture a guess, I'd expect it to be more sensitive due to the sulfur. I'm not trying to scare you, just trying to instill a determination to be safe and treat it with respect. It's still well within the realm of safe to use.

 

I haven't heard any reports of this mix gradually degrading or decreasing in performance over time. Generally speaking, a shell is fairly well sealed up and should be fairly stable.

 

I haven't heard of sulfur and aluminum reacting in the presence of moisture, but nitrate certainly can. I think justvisiting's experience with his scoop shows this. It's also fairly common in glitter stars. Read up on this if you want to learn a little more. Glitter stars are often kind of the perfect storm of conditions to make this happen, and it's extremely rare an ignition ever happens. If you want some added stability, or at least peace of mind, I'd suggest adding a couple percent boric acid. I wouldn't be too worried though overall. Once sealed a shell shouldn't be absorbing or allowing much water in even in the event of an accidental spill, leak, etc. If enough water is present to penetrate a shell, I'd think there is also plenty enough to thoroughly soak it to the core and render it inert.

 

Thanks Mumbles, really helpful :)

 

I guess i got the idea of KNo3/AL/S being less sensitive to static and friction because i seen a few reports of hammer friction tests being done on it. But you can't trust much on youtube right! :)

 

Just how dangerous is this comp would you say? Is static spray necessary when using the diapering method?

 

Do you know much about Barium Sulfate + Eckart dark aluminium? Is this any more stable than the other mixes?

 

Not even sure i want to use flash. Just looking for something to give me a more even break on the 35mm aerial shells made with film canisters. I want my film canisters to be D1 glitter + TT. I find that with BP it just blows the top off the film canisters. The canisters don't break evenly with BP they create more of a consumer rocket effect.

 

Would a whistle mix be more safer? Can whistle mix be made without potassium chlorate/perchlorate? As these chems are unavailable for amateur chemistry usage in my country.

 

I seen a composition for whistle mix with sodium benzoate and potassium nitrate? But the source didn't look very credible so not sure how effective this would be.

 

Just trying to master these fireworks while staying within my local laws and prioritizing safety.

Edited by PyroTop
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Slow flash is a standard in China for cakes and small shells in 1.3 category as well as some firecrackers. They store them for years at times before being sent to another country where it could sit for years more..

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Does Ba(NO3)2 function much differently than KNO3 in slow flash? Besides having more oxygen per unit mass and producing more light...? How about hybrid flash with Ba(NO3)2/KClO4 (Ive seen some formulas floating around)?
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The storage properties for any compound depend a lot on the local humidity and the quality of the package.

 

I have some theatrical (prox) flashes that spit balls of flame because they got damp.

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  • 3 months later...

This is kno3 flash with added fine mesh titanium

They are 1 inch inserts and do great when confined but burns like black powder unconfined. Storage is fine but needs to he well sealed from air.

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Hi pyropro one solution to your problem might be to confine your little cans more, perhaps with string or a paper wrap if you have room.if they won't fit your gun after this you could always roll some case's that will allow you to spike them .B
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  • 3 weeks later...

First of all hello to all pyro hobbyists, i am a new member here (please excuse me for my English sometimes sucks :D )!!! Second of all this composition isn't slow if you manage to get ultra fine particles of your ingredients! I personal put this composition in coffee grinder to blend it (with caution make a small burst at the time the first time i try it but this is dangerous because of heat and friction of a blade ) and second i put it in a ball mill with glass marbles from the top of the whisky (you know the small one) for an hour to blend it complete but the first time i put it in ball mill i take 50 meter cable and put it away to try it ! Nothing happen! But i don't recommend to anyone to try it at home and even someone try it i am not responsible! I try this two at my one risk! And third i had stored about 400g from extract salute cakes for years in a cadbury can and nothing happen again! And i never use it because i gave up the hobby for 12 years of accident witch i make at my own knowledge and my own stupid and scares me to hell...! i hope i help you guys with my experience!

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  • 1 month later...

First of all hello to all pyro hobbyists, i am a new member here (please excuse me for my English sometimes sucks :D )!!! Second of all this composition isn't slow if you manage to get ultra fine particles of your ingredients! I personal put this composition in coffee grinder to blend it (with caution make a small burst at the time the first time i try it but this is dangerous because of heat and friction of a blade ) and second i put it in a ball mill with glass marbles from the top of the whisky (you know the small one) for an hour to blend it complete but the first time i put it in ball mill i take 50 meter cable and put it away to try it ! Nothing happen! But i don't recommend to anyone to try it at home and even someone try it i am not responsible! I try this two at my one risk! And third i had stored about 400g from extract salute cakes for years in a cadbury can and nothing happen again! And i never use it because i gave up the hobby for 12 years of accident witch i make at my own knowledge and my own stupid and scares me to hell...! i hope i help you guys with my experience!

You're very lucky that you didn't get severely injured or killed using a coffee grinder and ball mill to mix FP.

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  • 3 months later...
It sounds unnecessarily dangerous. The whole point of adding sulfur would be to lower the ignition temp. This isn't usually an issue for Mg flash.
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  • 1 month later...

I cant post yet, but can anybody tell me why my rockets keep exploding?

Kinda hard to say without video. Our the spec's on how your making them. Fill us in on your process of making them and I'm sure someone can help.
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