823 replies to this topic

[digger]

i don't understand what is meant by commercial flash powder ?

we can't buy any fireworks where i live but i didn't think you could buy, say a kilogram of flash powder any where, is it what profesional pyrotechnists put in their reports/breaks, ?

Edit :- what ever it is it looks perhaps under oxidised,, and i would say its crap,,, my BP is as quick as that,

I assume that the flash is obtained form dissection of fireworks. I have tested commercial flash with similar results, however it is a different beastie when a little confinement is offered.

It would appear that the main difference is the aluminium flake size rather than the level of oxidiser present. I assume that the Chinese use cheaper aluminium than the super fine Indian and German varieties.

[Potassium chlorate]

You could actually buy flash in Sweden without a permit until 1994, and it was nitrate based; which the commercial stuff most probably is in the video.

That quantity should be even more powerful, though; I mean the German Black stuff.

[spanner]

I took commercial to mean taken from a OTC consumer device. But yeah, it's s l o w- whatever it is.

Possibly taken from one of the new-spec fireworks? BP with a little bit of flake Al is kind of what it looks like.

EDIT- Just saw this, in the Info box (sic):

"the first two both have ratios of 70/30 KCLO4 to Al powder just they have different Al powder the first has Indian Blackhead the second has Eckart 5413 H-S and the final flash powder is commercial taken from 4 or 5 blackcats" END

The amounts are hard for me to judge as to quantity. There's nothing to really judge scale until he reaches in with the punk stick, and I can't really tell if there's a tall pile or a flatter one.

Point is, 5413 is "hotter" than Indian "Blackhead".

BTW, I have always heard that the term "Blackhead" came from the drum lid color that Eckhart ships their 5413 in.

Anybody else know where the term came from?

Edited by spanner, 14 January 2009 - 12:56 PM.

[Potassium chlorate]

In Europe it's often just called "German Black". It's more probable that the name derives from the fact that the Al isn't "silver" coloured but blackish in colour.

Edited by Pyroswede, 14 January 2009 - 01:09 PM.

[Mumbles]

I dunno where the "blackhead" term came from. There is a bluehead and yellowhead as well. The drum color makes sense to me. I know for a fact that 5413 comes in a black drum.

BTW, all these fine flake Al's have stearin or stearic acid in them too to prevent oxidation. At the size of the particles, if a legitimate oxide surface existed, it would consume a significant portion of the metal. You want to keep it from oxidising. Thats part off what makes it so reactive.

[Potassium chlorate]

I never saw a drum with German Black. I buy it in plastic cans which contain from about a pound to a few kilos.

[MDH]

I assume that the flash is obtained form dissection of fireworks. I have tested commercial flash with similar results, however it is a different beastie when a little confinement is offered.

It would appear that the main difference is the aluminium flake size rather than the level of oxidiser present. I assume that the Chinese use cheaper aluminium than the super fine Indian and German varieties.

The Chinese utilize bright flake aluminum for safety purposes as well as inexpensive production. The composition, which while I won't directly quote is somewhere around 7/4, is compatible with a wide variety of additives which produce different effects. The exact same composition can be used for stars, sparklers and a base for fountains and comets.

I am thinking of, sometime in the near future, writing something here on UK pyrotechnics about multipurpose compositions. It's fascinating stuff...

Edited by MDH, 16 January 2009 - 03:24 AM.

[digger]

The Chinese utilize bright flake aluminum for safety purposes as well as inexpensive production. The composition, which while I won't directly quote is somewhere around 7/4, is compatible with a wide variety of additives which produce different effects. The exact same composition can be used for stars, sparklers and a base for fountains and comets.

I am thinking of, sometime in the near future, writing something here on UK pyrotechnics about multipurpose compositions. It's fascinating stuff...

Any news on your multi purpose formula article?

I was reading a thread on passfire today on flash. Has anyone experimented with AP/MgAl flash with a 70/30 primer?

[Vic]

I was reading a thread on passfire today on flash. Has anyone experimented with AP/MgAl flash with a 70/30 primer?

Why would you need to prime AP/MgAl flash or are we talking about flash bags as the initiator?

Edited by fflach, 20 March 2009 - 11:19 PM.

[digger]

Wy would you need to prime AP/MgAl flash

Oops edit due to not reading properly after a few sherbets. Yes a flash bag primary charge.

As I understand it, if you use it neat it has a detonation velocity of around 800m/s (in small amounts it will not even produce a bang if just lit) but it if you use a primer charge it doubles the detonation velocity to 1600 m/s so you get more bang for your buck so to speak (esp as it is a gas volume producing flash unlike most). Not that I have any experience with it any way at all.

Edited by digger, 20 March 2009 - 11:25 PM.

[MDH]

Any news on your multi purpose formula article?

I was reading a thread on passfire today on flash. Has anyone experimented with AP/MgAl flash with a 70/30 primer?

I didn't think it was worth while because I thought it was sort of a rule of thumb that one composition treated differently in a variety of environments is a common practice among pyrotechnicians - for instance, using nitrate flash as the break and the stars at once - and people wouldn't need the information. However seeing as people are interested I could probably start working on it.

I am not a member of passfire currently but I may be at some point of the future. By AP do you mean Acetone Peroxide or Ammonium Perchlorate?

[a_bab]

He is obviously talking about Ammonium Perclorate.

This is not the tootsie forum.

[enabe]

Right I know flash powder is a taboo subject but I am currently trying to make it, as much as I hate the stuff, and it will not work no matter what I do. I am using the standard 70/30 perc, aluminum formula and the diaper method for integrating them both. The aluminum is from Tiranti and is pretty good. The problem I am getting is that the dam stuff just will not burn fast at all, it is worse than un-milled bp! I just ain't sure as to what the problem may be. I also have tried the kno3 based flash using the same parts and it's still, how can I put it...... SHIT!!


It burns more like a fountain mix when confined producing a nice bright light but nothing more. Any help would be appreciated, I am making the stuff for my cakes finally.

may i ask what "the diapermethod for integrating them both" is?
is it a way of mixing the stuff?

[knackers]

mixing the chemicals together on a sheet of paper by lifting the sides and corners alternatively, therefore avoiding any friction that would be caused by mixing it with a spoon or spatula in a bowl,

[sir steve]

He is obviously talking about Ammonium Perclorate.

This is not the tootsie forum.

You either dont have KP or its not aluminium powder, Anything finer than 100 mesh will explode with tremendose violence-

Steve