milling, granulated stars, lift charge mass

[starburst]

Hello, can anyone answer my questions?..........

I have a question regarding starburst compositions.

Whilst I certainly would NOT attempt to ball-mill a burst composition containing sulphur and/or metal powder, (i.e Al/Mg-Perchlorate), I have thought about ball-milling a DAMP K perchlorate-charcoal burst composition. However, I also have serious reservations about ball-milling even a damp, sulphur-free K perchlorate-charcoal starburst composition. K perchlorate is more sensitive to static than K nitrate and I suspect that ball-milling even a damp, sulphur-free K perch-charcoal composition is dangerous.

I certainly will not try to ball-mill a perchlorate-charcoal composition if it is too risky and, as such, I do not recommend it to other pyro's, either.

How is it possible to safely mix such a composition in order to obtain a homogenous mixture, without resorting to ball-milling?

What about if I gently mix SMALL quantities on flat paper, without confinement, using a cardboard or wooden spatula or spoon? I would'nt even try mixing in a mortar- pestle, because there is a risk of compression, static or sparks. Also, the shape of a ceramic pestle mortar would confine an explosion or deflagration, if it occured.

Is 30-33 micron aluminium finely divided enough to be used as a flash-starburst composition?

Ordinary K nitrate-based BP is not powerful enough to burst small shells- I also like a report to accompany the star-burst. This is my reason for trying perchlorate-based starburst compositions.

I refrain from using K chlorate altogether- even if sulphur and possible ammonia formation (nitate-metal reduction reactions) are ruled-out.

I never compromise safety.

What is a good method for making microstar granules? I am not just talking about dragon's eggs- I am referring to any granulated microstar compostion. I think that the damp star composition is pushed through a suitable mesh and the granules are dried. Once dry, they can be incorporated into the parent star mix. Am I correct?

How are the microstars incorporated into the parent star mix?

I would like to try a colour-change star composition, i.e, red to green, and so on. How is this achieved? Any ideas would be greatly appreciated.

One last question- is there a calculation that can be used to work out the X mass of lift charge needed to send a shell of X mass to a desired height?

 

Many Thanks for your advice.

[styropyro]

When I burst a shell, I don't ever need to do anything fancy with compositions, I just coat rice crispies with some damp meal powder and let them dry, and I add about 3 grams of whistle to the middle of a 3 inch shell. It makes a good bang and I get a nice break (but not perfect, I need to paste my shells better.) but I try to refrain from bangs over where I live so I don't use too much of the nasty stuff in my shells. If you add too much your stars might get blown blind.

 

30-35 micron wouldn't work very well in a break charge, but you could always use it in glitter compisitions

 

For microstars I just push the damp comp through a larger mesh screen (I don't want the microstars too micro) and then I tumble the damp microstars in my ball mill (without the milling media) with a little bit of meal powder mixed with 3% dextrin to prime them. I take them out of the mill after about 15 minutes and then let them dry. Then they are good for me.

 

And for color changing stars, all that is happening is a star is burning off its outside color compisition and then burning another layer of compisition. To get this effect you have to roll your stars. A good tutorial is here > http://www.unitednuclear.com/stars.htm

 

For black powder you have to test on your own because everbody's homeade black powder is different. Use a three inch mortar and a baseball to test out your powder. Just toss in a tenth of the weight of the baseball in black powder and see how high the baseball goes. If you don't like how high it went use more black powder the next time. If it went real high use a little bit less black powder and keep on going from there.

 

Hope this helps!

 

P.S. sorry I couldn't link the link above. I think the forum's clickable smileys aren't working either, I just had to type them in.

[starburst]

Thanks for your advice.

It is a pity that United Nuclear do not ship outside the US. They have some impressive chemicals- not sure about their potassium or sodium metal, though! (dangerous stuff!).

Problem is that I can not find a source for buying potassium benzoate used in whistle mix. I could make the chemical if I had some benzoic acid and potassium carbonate or hydroxide.

I was thinking of developing a 'hybrid' black powder, consisting of ordinary 75:15:10 blackpowder mixed with 70:30 K perch/charcoal burst composition.

This might be effective as a bursting formulation for starbursts.

Sulphur could be included in the K perc/C mixture, so that the K perch does not 'rob' the sulphur from the KNO3.

In the past I have tried a similar mixture, with KClO3 intead of K perch; the results were pretty good- a powerful mix.

However, I would NEVER use KCLO3 again in this mix, because of the dangerousness of KClO3 and Sulphur mixtures.

No one should ever mix sulphur with a chlorate!

NEVER ball- mill anything other than ordinary 75:15:10 nitrate blackpowder.

Ordinary blackpowder mixed with K perch will have an increased sensitivity to shock, static and friction, especially when sulphur is included. So, if anyone wishes to try this mix, please be extremely careful, mix only VERY SMALL amounts (less than 1 gram) and do NOT ball-mill!

If anyone has tried a similar mixture to produce star-bursts, please let us know the result.

[styropyro]

The only problem is the Perchlorate-sulfur incompatability. I didn't know about this till a few months ago. You probably have taken a tiny amount of sulfur and potassium chlorate and hit it with something like a rock. I makes a good sized pop and shows how sensitive the mix is. Now try the same with potassium perchlorate. It takes more effort to do but it does explode when hit pretty hard. That's why I try to refrain from sulfur and potassium perchlorate to be in the same mix. But I still use perchlorate mixes (like whistle) by black powder in shells because I am pretty far away from shells when they are launched so if it were to somehow flowerpot from the shock I would be a safe distance away.

 

But your mix of Potassium Perchlorate and charcoal mixed with meal powder would probably work something like benzolift. Benzolift is some fun nifty stuff, but you have to be careful about sulfur and the perchlorate. But I will give some of this mix you suggested a try tonight or tommorow and I'll give you some of the ratios I used if it works.

[pa_pyro]

If you can't find pot. benzoate maybe you can use sod. benzoate. It works fine for my whistles(not as strong a k benz or sally though, I think), and I bought a kilo of it off of ebay for about 6$ and shipping. It makes good hand-pressed whistlers, but my rockets never seem to leave the ground. Darn I need to shell out for a press and proper tooling.

[styropyro]

I tried some of the charcoal/perchlorate/meal you suggested. But I want you to know first that the charcoal wasn't very fine, and the ingredients weren't mixed well enough. I just tried it for experimental purposes. I used the mixture 1 part willow meal to 1 part 60:40 Potassium Perchlorate/charcoal (not ground enough.) Here is the video> http://media.putfile.com/charcoal-perchlorate (sorry the forum's buttons for posting seem to be down so I cant shorten the link.) To be honest I don't think this mixture is worth it, it almost seems like watered down BP. But maybe if I mill some willow it might work. But now that I think about this mixture, this *kind of* seems like watered down H3. H3 uses chlorate though. But I will post results once I test it with proper ingredients.

[Mumbles]

Perc-C is a weak burst as it is. Perhaps some KP is in order for you. It involves the Perc-S incompatibility. The charcoal waters it down as it were. KP is a standard burst used in industry. It's up to you whether or not you want to take the risk, but Perc-Sulfur is not nearly as bad as Chlorate-Sulfur in all reguards. I think it is was only impact where it was comparable, so don't go around hitting it with a hammer.