flash powder help

[lmodest]

-- Edited July 4, 2011 by lmodest

[Seymour]

The problem is almost certainly an issue of surface area. Your Aluminium, and possibly your Potassium nitrate are not fine enough. The Aluminium used in good flash powder is quite different to that used in most other pyro applications.

 

Ammonium nitrate is pretty useless in pyrotechnics. In most cases it's a really sluggish oxidiser, and that along with it's hygroscopicity doom it. While it may look like a great oxidiser in theory, plenty of energy, oxygen and fully gasious products, it's just a pain in the arse.

 

I don't want to discourage you from pyrotechnics, but flash powder is incredibly dangerous. Considering the consequences of what could go wrong due to a misunderstanding, or decision made due to lack of awareness, it's fairly unanimously agreed that you should have learned a lot on the subject before you venture as far as mixing it. While I think everyone appreciates people asking questions (So you can get answers relevant to your pyrotechnic success, your safety ect), questions such as yours are a fairly good indication that you have some learning to go before you have it all covered.

 

I'm sure the Aluminium you have will make decent glitter stars.

Edited July 4, 2011 by Seymour

[lmodest]

-- Edited July 4, 2011 by lmodest

[mabuse00]

A little excerpt from the forum rules:

Those simply here to try to learn how to make salutes and other similar devices should save the moderators the trouble of banning them, and simply leave. Discussion of salutes, flash powder, and other similar topics is discouraged and may only be done in the most intelligent of manners. Those not abiding, are not welcome here.

 

ive been studying " flash powder " and the chemicals in it for awhile now

As flash is one of the most simple stuff to make you should have no trouble understanding whats wrong.

Also Pyrotechnics is not the kind of hobby where one should simply try to "get it to work" quickly without going into the theoretical background.

 

Seymour allready explained what your problem is.

 

edit:

Here's a good summary: http://www.pyroguide.com/index.php?title=Aluminium_%28Powder%29

Edited July 4, 2011 by mabuse00

[ulajo]

I cant see Imodest's posts but listen to Seymour about the Ammonium Nitrate.

Pyrotechnics have nothing to do with Ammonium Nitrate, i would avoid it by a simple rule about that chemical: "it can spontaneously detonate under influence of rapid rise of temperature and pressure especially when mixed with aluminum dust".

If i would have some of it laying around and didn't grow any growing culture than i would use it to synthesize sodium nitrate with it. Here is an info http://www.hoby-pyro...e_synthesis.php

Edited July 12, 2011 by ulajo

[Mumbles]

That's like saying TNT can spontaneously detonate when a blasting cap goes off inside of it. Well yeah, that's the point.

 

Sodium nitrate has very few to no real applications in pyrotechnics due to how hygroscopic it is. It makes it rather hard to work with and store at times. Thats not to say ammonium nitrate has many more.

[r1dermon]

Sodium nitrate makes good black powder. Goex has a blasting grade of powder that utilizes the chemical.

[Ralph]

Sodium nitrate makes good black powder. Goex has a blasting grade of powder that utilizes the chemical.

 

Make bp with sodium nitrate for a while , make a couple shells than let me know how fun it is to work with

[50AE]

I doubt it, BP made with sodium nitrate is quite slow. It makes a cheap yellow star though, if one likes sodium's yellow.

[dagabu]

Here is a link to the last time we did a round with Sodium Nitrate.

 

LINK

 

-dag

[r1dermon]

slow BP has many an application. maybe not in "fireworks" but it's certainly "pyrotechnics".

 

 

Edited July 12, 2011 by r1dermon

[Ralph]

Im not talking burn rate Im talking the fact that it turns into a soggy mess one day you have working blackpowder (with the NaNO3) once your pasting is dry youll have something that wont even burn and all your hard work will be in vain

[Mumbles]

Yes, sodium nitrate is the basis for the B grade blasting powders. I'm sure we all know and love 2FA, it's an A grade blasting powder. Assuming they use the same size grading, it'd be 2FB for the sodium nitrate version. It's slower, and apparently heaves better than potassium nitrate. If you include military and civil applications in with pyrotechnics, then yes you're right. I was talking mostly in the display fireworks side of pyrotechnics. It has a few uses, but not many.

 

Anyway, this is getting significantly off topic.

[dave321]

Yes, sodium nitrate is the basis for the B grade blasting powders. I'm sure we all know and love 2FA, it's an A grade blasting powder. Assuming they use the same size grading, it'd be 2FB for the sodium nitrate version. It's slower, and apparently heaves better than potassium nitrate. If you include military and civil applications in with pyrotechnics, then yes you're right. I was talking mostly in the display fireworks side of pyrotechnics. It has a few uses, but not many.

 

Anyway, this is getting significantly off topic.

 

that may be the case, and i know where you are coming from, but......

why did pine buff arsenal design an ignition disc consisting of sodium nitrate, charcoal and gum arabic + water,

when they were reformulating their red and violet smoke grenades................i too would expect some moisture pick up................

 

reference ESTCP Project WP-0122, SEPT 2008

 

http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=ADA477977

 

PAGE 19 of the report and Page 28 in the pdf

 

dave

[FrankRizzo]

Im not talking burn rate Im talking the fact that it turns into a soggy mess one day you have working blackpowder (with the NaNO3) once your pasting is dry youll have something that wont even burn and all your hard work will be in vain

 

That's not true, Ralph. Sodium nitrate is hygroscopic, but it's not deliquescent (like calcium chloride for example). It does make serviceable BP, but the power will drop considerably on humid days, so it needs to be packaged in something like a thin sandwich baggie before being installed on the shell. The end spit from a quickmatch leader will easily ignite the powder through the thin plastic.

[r1dermon]

NaNO3 is significantly cheaper in large quantities than KNO3 as well, which is why it is used for blasting. it is an acceptable form of black powder, and while it's burn rate is moderately slower than traditional BP, that can be overcome by tailoring the specific granule size. when you're using 100lbs of black powder at a time, the dollar amount adds up NaNO3 vs KNO3 black powder. as far as heaving goes, sodium nitrate black powder, i would imagine, due to it's tamed burn rate, would be better suited for lifting larger shells, like 16"+. although as pointed out, it is quite hygroscopic, so it's practicality is limited by how well it is protected from humidity. the biggest factor, at least as far as i can tell, is the cost however.

 

mumbles, i know you're somewhat knowledgeable in the field of chemistry, i'd be interested to know why NaNO3 is seemingly preferred in smoke mixes, rather than KNO3.

[Mumbles]

I'll be honest, I haven't really seen any smoke mixes made with sodium nitrate. The nitrate sugar type of smokes are not good enough for military or other practical purposes. Most of the practical formulas I've seen are either chlorate or HCE based. I'm sure there are sodium nitrate based smokes out there, but frankly I really don't care. I really only make display fireworks, and the thick slow burning smokes have little use to me. It's probably used over potassium because it burns slower.

[dave321]

sodium nitrate was only used for the ignition disc.........

the coloured smoke was chlorate sugar based

 

dave

[gordems]

hello iam the first time that i right here and i have a question about flash powder like bomb shell (beraq)

if you have aluminiom, and putasiium percklorat, composition and have some black powder with silicon to make some delay is it good or not?

 

 

 

 

[Mumbles]

You're from Malta, ask someone who knows how to make Beraq shells. In general I've heard they use varying amounts of barium carbonate or gum arabic in combination with their BP to form the delays.

[gordems]

if silicon is in contact whit aluminium is danger or not pls?

 

 

[Seymour]

I really don't think Si and Al are incompatible.

[pyrojig]

No, it is not incompatible. The Al and SI can create a thermite in the proper ratios. Some SI primes have a bit of AL in them. These are very hot and will ignite just about any star. Edited July 15, 2011 by pyrojig

[Mumbles]

Pyrojig, are you thinking about Al and SiO2 for the thermite? Al and Si can probably still react, but I don't see it being a very exothermic reaction.

[50AE]

It's very difficult to make them react. A helping chemical has to be introduced. I heard more aluminum with the addition of sulfur does the job. I'm planning to try a SiO2/MgAl mixture though.