Blue star

[davidg]

Ammonium Perchlorate 74%
Copper 300 mesh or finer 11%
Stearin 11%
Parlon 4%
Dextrin to bind +5%

Method: sieve chemicals (minus copper) through 100mesh screen. Put in zip-loc bag add copper and shake to blend.

Do not mix with chlorates. Prime with:
Potassium perchlorate 75
Air float charcoal 15
Red gum 10
Dextrin + 5
Silicon +5 (or Fe/Si)

May not need silicon

AP is Hygroscopic so stars may benifit from a coating of wax or NC

[Niall]

My only pointer is that metal fuels should be avoided with ammonium perchlorate as they can react unfavourably, and at an increased risk in the presence of water.

[davidg]

True,forgot to mention that. I used IPA only to wet this formula. Maybe red gum would be better in place of the dextrine

[Niall]

I'd keep the balance otherwise you might just end up with a goo, where the dextrin will keep some substance during processing.

[Paul Moulder]

Might be of interest to someone if you can find the Dicyandianide. A blue star formulation given to me by an Italian friend with a factory in China.
Potassium Perchlorate 42%
Sulphur 15%
SRGS 5%
Copper 2 Oxide 24%
PVC 5%
Dicyandiamide 9%

I tried this star from a star gun, it's a very nice blue but cut it smaller than usual it has a long burn time.
Bind with water approx 10% for cut stars less if pumping. Not tried rolling it.

[Pyro-Gear]

Interesting Paul I can get that, price around £17 a kilo I’ll give it a go.

[sambo]

Seriously tempted, thank you Paul, might be good to look at this for a PVB blue Ken. Ken, can you put me down for a kilo of Dicyandiamide ?

Sam.

[Pyro-Gear]

Sam I would go for my post new blue it works great, i assume Dicyandiamide must be the binder.

[Lloyd]

Gas-producing fuel, Ken, according to the source who gave it to Paul.

It makes the flame envelope larger for a given burn rate, thus helping to keep the temperature down, and increasing light output. (just by its size)

The SGRS is the binder.

(oops! you said "your" blue... not sure about that one... <G>)

Lloyd

[Pyro-Gear]

[quote="Lloyd"]Gas-producing fuel, Ken, according to the source who gave it to Paul.

It makes the flame envelope larger for a given burn rate, thus helping to keep the temperature down, and increasing light output. (just by its size)




Yep but you can do that with hexamine.

[Pyro-Gear]

Potassium perchlorate 48.
Copper oxide 18.
Parlon 12
Hexmine 4
Magnalium 4 250#
Dextrin 4.

[Lloyd]

Yep but you can do that with hexamine.
------------
Yep.

So the Chinese have chosen not to use hexamine for that. It might be partly due to its vapor pressure vs. dicyandiamide (about 20:1 difference, cyanoguanadine being the lesser of the two)

Lloyd

[Pyro-Gear]

The Chinese would use whatever was the most economical.
Controls were put in place to divulge the contents of Chinese fireworks in 2013 I have the data base, all I am saying is hexamine will work.

[Pyro-Gear]

http://www.phmsa.dot.gov/pv_obj_cache/p ... 1-2012.pdf

[Lloyd]

I agree that it will work, Ken. I've made some stunning hexamine blues.

That wasn't my point, exactly.

Part of my point was, they get to choose what they want, and what they want is usually what's least expensive and will still do the job.

The other point is that they make their fireworks sometimes YEARS in advance of delivery, then store them in hostile environments (sun-bleached steel containers, sometimes for years).

Anything that might deteriorate the effects during that storage time is considered not-acceptable. Hexamine 'gasses off' fairly easily. DCDiamide doesn't.

I do not KNOW that's their reason for using it, but it could be.

Lloyd

[Pyro-Gear]

Well Lloyd Dicyandiamide is one I have to look in to.

I have a SKPE meet in the morning I will bring up the Dicyandiamide and see what the reaction is.

I have 300 grams of Dicyandiamide on the way to test, but fail to see why the Chinese would be using SGRS still let’s see how the research go’s.

[Lloyd]

but fail to see why the Chinese would be using SGRS still let’s see how the research go’s.
------------
Because, when they can avoid expensive solvents, they like to roll stars with water.

Lloyd

[Pyro-Gear]

Got YA, OK SGRS it is then I have kilos of the stuff.

[Paul Moulder]

I did ask the guy who gave me the composition what the purpose of the Dicyandiamide was. He said it helped to provide more gas production, this gives a bigger flame plume and a brighter, purer colour.
It also gives a longer burning duration
In the case of the comp having metal sparking additives such as Titanium, Ferrotitanium etc the gas production helps expel the particles from the star.


A search of some of the patents on google shows it's use in some flare compositions

eg
Green..... Barium Nitrate 66% Dicyandiamide 17% Nitrocellulose 17%
Red.........Strontium Nitrate 55% Dicyandiamide 25% Potassium Nitrate 6%

[Pyro-Gear]

I would imagine that the star would be very viable for such things as insert’s and small rocket headers due it’s burn rate, Paul in your opinion and I assume you have tested the formula what size star would you use in say a 3 inch shell, I normally roll to 10mm including prime but I am a little worried on the burn time as you stated it was a little slow, cheers Ken.

[Paul Moulder]

Ken I only make cylinder shells so all my stars are cut stars and I rarely make cylinders smaller than 4 inch.
I've tried the star in a star gun and from those observations I would go for a 5/16 plus prime for a 4 inch shell if it was a single colour shell. A 5 inch I would use 3/8 if using them to 'centre fill' the shell and maybe 5/8 if making puped stars to stack inside the case.
I will be spending a week or 2 at my shop next month and intend to make a few test shells. Will post results.

[Pyro-Gear]

Thanks for the information Paul I have the Dicyandiamide now so I will running a few tests at the weekend, I think Dicyandiamide could be a useful addition to the store Cheers Ken.

[biffo]

Hi Ken it's now a few months and another year,what are your thoughts about the substance now ,I know you are busy with other things at present did it hold your interest for long? Regards B

[sambo]

Hi Biffo, I'm not sure how Ken got on but in the end I synthesized Dicyandiamide from calcium cyanamide ( I have a large bag of this as it's a type of fertiliser ) and ammonium bicarbonate. This didn't work all that well for me in this blue as I think there was some contamination in my product ruining the flame. However, it is an EXCELLENT gas generator. Quite incredible in fact in that sense. I put it to use recently with some lithium flame tests as it has been bugging me for an age that I can generate a beautiful red crimson flame with a torch but nil at the burn point of the composition. Adding Dicyandiamide generates a 1m x 1m cloud of lithium filled gas which you can hold the torch in the midst of and hey presto generate a beautiful red flame almost a meter away from the composition burning point - I'd imagine you could use this to create a strange and probably quite impressive type of flame thrower. Sorry if that's not quite the answer you were looking for and veering off topic.

Sam.

[Boophoenix]

Sambo, it would be really awesome to see video of some of these experiments. I YouTube many of mine and just unlist them without the link they are invisible it seems, but still easy to share.

[Tom Schroeder]

Dicyanamide is often used in the black powder substitutes like pyrodex. it was also covered in a Chinese patent as a component that could be added to color stars to increase burn times but not affect the color or brightness. 5 to 15% was recommended.

Tom

[Boophoenix]

Man, I spent most of last year acquiring supplies to try to avoid the " I wanna try this, but wait I don't have that syndrome " and here y'all go that's about a dozen new things now. Lol

[biffo]

Hi Sam could you use that cloud of escaping gas by having Ti or Al dropping from the lit star and appearing red in the tail,like red glitter would.B

[sambo]

Man, I spent most of last year acquiring supplies to try to avoid the " I wanna try this, but wait I don't have that syndrome " and here y'all go that's about a dozen new things now. Lol

yes, my name's Sam and I'm a pyrochem addict too. I can't get clean either.

B. Yep - had considered that very thought - you never know? There is something about the propane burning from the torch - either the temperature, the water produced by combustion forming the hydroxide or some other component of the gas that seems to do this. I'm working on a new synth for Lithium Peroxide I'll let you know. I agree, videos would be useful - just lazy and must try harder.

[sambo]

Just for you boo I've started a new thread with a video in it for you to see the phenomenon I'm talking about.

Sam.