65 replies to this topic

[darkfang77]

yep needs tweaking id say, but a flare is supposed to get you noticed lol, it did burn for a while but the vid was edited, guess it wasn't that exciting
sigh, its not often you can try such things out.
i used about 80g pressed in a 35mm card tube, very messy to make,
the prime was tiger tail with mixed ali,and a boric acid buffer, ignited it with a silver flying fish fuse, these are the hottest i believe.
weingarts starting fire
barium nitrate 4
kno3 3
sulfur 1
shellac 1

Hmm. It seems that barium nitrate seems to be the holy chemical. You've mentioned it pretty much in all your formulas.
35mm thickness card tube is over an inch thick, there goes my theory 1/3 inch.
I don't want a flare which screams out "call the fire brigade, possible house on fire". I want a flare which screams "awesome white, near death experience light".
Any bulkers used/usable? Either no-one has read this line or skidded over it, or they don't know. Which is it?
I need a notepad to write down all the formulas I'll be testing lol.

[seymour]

Wood meal is often used as a bulking agent.

However, there are other ways to get the composition to burn for a longer time... simply use a longer tube with a smaller diameter. Easy.

As for wall thickness, what is wrong with the wall burning away?

I personally suggest going with a 1mm thick wall tube. It will be consumed as the composition burns. A thick walled tube will be unusable after you've burned the flare, so it makes little difference to you from that perspective.

Most of Chris M's formulas are from sources where the author had access to the full range of contemporary chemicals. It so happens that Barium nitrate is the best oxidiser for white flares, and since they have it, they use it.

This certainly does not mean that you have to use it. Potassium nitrate with magnesium will certainly fulfill your ambitions. However Barium nitrate is better, so most formulas will include it.

As for the toxicity of Barium nitrate, it is toxic, and it can kill you. We must be open about that. The lethal dose varies from case to case, but on average it seems to take four grams to kill someone. That's quite a significant quantity when you think about it. How would you ingest a full table spoon of ordinary salt by accident? Let alone an even stranger tasting salt. If you take the basic precautions, such as washing your hands after use (or wearing gloves) and wearing a dust mask if you are going to be working with the powder inside, you'll be fine.

If you do ingest it, you can save yourself by ingesting a soluble sulfate, since it will form Barium sulfate which is so insoluble, that it is non-toxic. Potassium sulfate is probably the best, since one of the ways that it poisons you is by depleting potassium in your body in some critical way, so replenishing potassium can save your life too. Victims of huge (many times the fatal dose) of Barium carbonate have been saved by eating Potassium permanganate of all things!

[darkfang77]

Wood meal is often used as a bulking agent.

However, there are other ways to get the composition to burn for a longer time... simply use a longer tube with a smaller diameter. Easy.

As for wall thickness, what is wrong with the wall burning away?

I personally suggest going with a 1mm thick wall tube. It will be consumed as the composition burns. A thick walled tube will be unusable after you've burned the flare, so it makes little difference to you from that perspective.

Most of Chris M's formulas are from sources where the author had access to the full range of contemporary chemicals. It so happens that Barium nitrate is the best oxidiser for white flares, and since they have it, they use it.

This certainly does not mean that you have to use it. Potassium nitrate with magnesium will certainly fulfill your ambitions. However Barium nitrate is better, so most formulas will include it.

As for the toxicity of Barium nitrate, it is toxic, and it can kill you. We must be open about that. The lethal dose varies from case to case, but on average it seems to take four grams to kill someone. That's quite a significant quantity when you think about it. How would you ingest a full table spoon of ordinary salt by accident? Let alone an even stranger tasting salt. If you take the basic precautions, such as washing your hands after use (or wearing gloves) and wearing a dust mask if you are going to be working with the powder inside, you'll be fine.

If you do ingest it, you can save yourself by ingesting a soluble sulfate, since it will form Barium sulfate which is so insoluble, that it is non-toxic. Potassium sulfate is probably the best, since one of the ways that it poisons you is by depleting potassium in your body in some critical way, so replenishing potassium can save your life too. Victims of huge (many times the fatal dose) of Barium carbonate have been saved by eating Potassium permanganate of all things!

The problem of using a thin wall which bursts into flames is:

• It will burn faster than the composition so the it will fall out if I hung it up.
• And I can wreck the effect by spoiling the light.

I will need to purchase some Barium nitrate I suppose, what's the going rate of the stuff? £4/kg? Maybe more?
What's wood meal? Wooden debris? Weingart states that a flare should be "3/4 inch diameter" and "18 inches long, exclusive of handle". So thats the specification I'm doing, maybe shorter though.

When you say barium salts tastes strange, it suggests that you have tasted it before, have you?

Hmm, I almost laughed when you said a barium salt can be made safe with a sulphate, imagine this scenario, I have just eaten 10 grams of barium nitrate (thought it was icing sugar), so I pop open my chems cupboard for a sulphate. What is the first sulphate I find? Why copper sulphate! Let's mix 20 grams of that (fatal dose) with some water and gulp it down. Cheers!


Then I was brought back to reality when I found out I only read half the post. Sigh. Potassium compounds stop your heart though, surely their would be some limit to the potassium you can consume?
What else was there? Oh yes! What is the purpose of Copper Sulphate in Pyrotechnics, so far I have found no possible use for it, I tried to make sulphuric acid from it (fail). I tried to mix it with some BP (fail, BP kept fizzing out). What possible use is there for copper sulphate???

[seymour]

Well, I have tasted barium nitrate, but that's besides the point. It is very salty, and ingesting large quantities of salt requires overcoming your bodies natural reflexes to spit it out, gag, or vomit. Essentially, accidentally poisoning yourself fatally is not a likely occurrence. By no means am I saying that you should be careless around it, but many people exhibit paranoia of this substance that goes far beyond the real risks.

* It will burn faster than the composition so the it will fall out if I hung it up.
* And I can wreck the effect by spoiling the light.

I must say that I doubt that a paper tube will burn faster than a flare mixture, though it is possible. As for disturbing the light, consider lances. They are coloured compositions in a paper tube. Coloured compositions are much more sensitive to the light being spoiled by the casing burning, and they tend to have very thin walls. Additionally, with a white magnesium flare, I really don't think that paper disturbing the flame colour is an issue at all. The flare flame will just be so many times more overwhelming that I doubt you will be able to notice the paper burning if you tried.

Hmm, I almost laughed when you said a barium salt can be made safe with a sulphate, imagine this scenario, I have just eaten 10 grams of barium nitrate (thought it was icing sugar), so I pop open my chems cupboard for a sulphate. What is the first sulphate I find? Why copper sulphate! Let's mix 20 grams of that (fatal dose) with some water and gulp it down. Cheers!


Then I was brought back to reality when I found out I only read half the post. Sigh. Potassium compounds stop your heart though, surely their would be some limit to the potassium you can consume?
What else was there? Oh yes! What is the purpose of Copper Sulphate in Pyrotechnics, so far I have found no possible use for it, I tried to make sulphuric acid from it (fail). I tried to mix it with some BP (fail, BP kept fizzing out). What possible use is there for copper sulphate???

Yes, copper sulfate is not a very good candidate for neutralizing soluble barium salts (note that if ingested insoluble barium carbonate forms soluble barium chloride). Certainly potassium can be toxic, hence it's use as the fatal injection in many executions. However, so long as you moderate yourself, and only consume a small quantity of it (comparable to the estimated barium ingested) it should save your life. Your body will certainly be sick, but unless you went crazy and consumed an excess of Potassium sulfate, you will be alive.


While it's good to consider what to do if you are poisoned (and in my opinion go and buy potassium sulfate), the best thing to do is avoid the poisoning in the first place.


Wood meal is very fine sawdust. Flour may work as a substitute. Still, I'll stick to my advice that a longer, thinner flare with no filler is possibly a better option.

I personally have only ever used copper sulfate for making other materials.

Mainly this includes adding it to Sodium (or ideally Potassium) benzoate in solution to precipitate Copper benzoate.

And also adding Zinc dust to a Copper sulfate solution to precipitate out copper metal dust.

Any soluble copper sat will work for both of these, so it does not need to be Copper sulfate. The sulfate's a spectator ion.

[darkfang77]

I must say that I doubt that a paper tube will burn faster than a flare mixture, though it is possible. As for disturbing the light, consider lances. They are coloured compositions in a paper tube. Coloured compositions are much more sensitive to the light being spoiled by the casing burning, and they tend to have very thin walls. Additionally, with a white magnesium flare, I really don't think that paper disturbing the flame colour is an issue at all. The flare flame will just be so many times more overwhelming that I doubt you will be able to notice the paper burning if you tried.

Ahh, I must be thinking about my fountains then, they kept singing off the sides, so the pressure wasn't as immense on the top, leading to a very flat and failed fountain.

While it's good to consider what to do if you are poisoned (and in my opinion go and buy potassium sulfate), the best thing to do is avoid the poisoning in the first place.

While potassium sulphate may be the chemical of choice to purchase when poisoned by barium, I have never seen it on the shelves of my local supermarkets/pharmacists.
Surely magnesium sulphate (epsom salts) would be a more easy-to-find alternative, unless it's too reactive to displace barium, where is barium anyway on the table of chemical reactivity. I am still finding out why Potassium chlorate with Ammonium perchlorate, although I'm thinking of something along the lines of exothermic displacement reactions causing a boom.

Wood meal is very fine sawdust. Flour may work as a substitute. Still, I'll stick to my advice that a longer, thinner flare with no filler is possibly a better option.

Gotcha, I think I will do some experimenting on this, perhaps two flares, one w/ bulking agent of fine sawdust (I have plenty of that anyway) and one w/out bulking agent.
I guess the one without bulking agent will probably do better however.

I personally have only ever used copper sulfate for making other materials.

Mainly this includes adding it to Sodium (or ideally Potassium) benzoate in solution to precipitate Copper benzoate.

And also adding Zinc dust to a Copper sulfate solution to precipitate out copper metal dust.

Any soluble copper sat will work for both of these, so it does not need to be Copper sulfate. The sulfate's a spectator ion.

Ah, so copper sulphate in itself poses no real use in pyrotechnics, I suppose you could use it as a colourant, but there are probably better chems out there.

More questions about the fountain!
With the composition you have stated:

60% Mg
30% KNO3
10% Charcoal / 5% Sulphur.

Can this composition be rammed? Or simply hand pushed?
How long can I expect a "unbulked" flare to last? <2 mins?

[pyromaniac303]

The main problem with copper sulphate is that its hygroscopic, so comps containing it that will be stored tend to absorb moisture. This can cause stars to crumble, or in severe cases actually turn into a puddle.

Also when you buy it, it may be fully hydrated, anhydrous, or a mixture of the 2 states. This makes weighing it out a nightmare, as the hydrated state weighs more and can throw off all of your measurements. The best way to get around this is to heat your hydrated (blue) copper sulphate gently over a flame, stirring quickly until it all turns slightly off-white. The change occurs at around 220 degrees, and you now have anhydrous copper sulphate.

Also don't under any circumstances mix it with a chlorate, as this results in a very sensitive and dangerous composition. Perchlorate seems fine, but don't take my word for it. It is always a good test for new compositions to place a small amount on a brick or solid surface and hit it at gradually increasing force with a hammer, to see if you can ignite it.

I have tried making blue lances, and it is possible to obtain a nice blue with it but they must be used immediately or sealed in an airtight container.

Such a formula may be:
Potassium Perchlorate 65
Copper sulphate (anhydrous) 10
Parlon 20
Sulfur 5

Bulking agents are used in industry where cost is important, but may reduce performance slightly. Most hobby pyrotechnists try and obtain the best colours and effects available, and as a very limited quantity will be made the cost is not usually much of an issue.

Just hand press it, I would not want to ram any composition containing metals, particularly magnesium as can sensitize compositions to ignition by friction and shock. Press it in small increments so that the powder is fully consolidated, maybe 1/2" to 1" at a time.

The burn time will vary on the mesh size of the ingredients, the tube length and how well mixed the composition is. You can press a known length of composition (preferably from the same batch) into a tube as a burn rate test to gauge how long the larger one will last though, if you are after a specific burn time.

Edited by pyromaniac303, 14 August 2010 - 11:46 AM.

[darkfang77]

The main problem with copper sulphate is that its hygroscopic, so comps containing it that will be stored tend to absorb moisture. This can cause stars to crumble, or in severe cases actually turn into a puddle.
Also when you buy it, it may be fully hydrated, anhydrous, or a mixture of the 2 states. This makes weighing it out a nightmare, as the hydrated state weighs more and can throw off all of your measurements. The best way to get around this is to heat your hydrated (blue) copper sulphate gently over a flame, stirring quickly until it all turns slightly off-white. The change occurs at around 220 degrees, and you now have anhydrous copper sulphate.
Also don't under any circumstances mix it with a chlorate, as this results in a very sensitive and dangerous composition. Perchlorate seems fine, but don't take my word for it. It is always a good test for new compositions to place a small amount on a brick or solid surface and hit it at gradually increasing force with a hammer, to see if you can ignite it.
I have tried making blue lances, and it is possible to obtain a nice blue with it but they must be used immediately or sealed in an airtight container.

Such a formula may be:
Potassium Perchlorate 65
Copper sulphate (anhydrous) 10
Parlon 20
Sulfur 5
Bulking agents are used in industry where cost is important, but may reduce performance slightly. Most hobby pyrotechnists try and obtain the best colours and effects available, and as a very limited quantity will be made the cost is not usually much of an issue.
Just hand press it, I would not want to ram any composition containing metals, particularly magnesium as can sensitize compositions to ignition by friction and shock. Press it in small increments so that the powder is fully consolidated, maybe 1/2" to 1" at a time.
The burn time will vary on the mesh size of the ingredients, the tube length and how well mixed the composition is. You can press a known length of composition (preferably from the same batch) into a tube as a burn rate test to gauge how long the larger one will last though, if you are after a specific burn time.

OK, I will hand press the composition. At the moment, I am making some cardtubes tubes for the flares, hopefully, once they're done I can post results. I will of course, need a rain-free day, hard to come by in August unfortunately.

[MDH]

That sounds a tad on the overfueled side. Not to mention parlon is not necessarily the greatest fuel with potassium perchlorate alone. I would say that a double decomposition reaction with copper sulfate and another reagent would be a good idea, and finding another fuel like stearin would also be helpful.

In my own experience copper sulfate is actually a very nice color donor, even with high levels of water in it. For the longest time when I first started pyrotechnics my basic mixture was simply sugar, copper sulfate and potassium perchlorate, which tended to burn a transparent, tall blue.

Edited by MDH, 14 August 2010 - 07:09 PM.

[darkfang77]

That sounds a tad on the overfueled side. Not to mention parlon is not necessarily the greatest fuel with potassium perchlorate alone. I would say that a double decomposition reaction with copper sulfate and another reagent would be a good idea, and finding another fuel like stearin would also be helpful.
In my own experience copper sulfate is actually a very nice color donor, even with high levels of water in it. For the longest time when I first started pyrotechnics my basic mixture was simply sugar, copper sulfate and potassium perchlorate, which tended to burn a transparent, tall blue.

That's strange. I once made some BP and put some Copper sulphate into it. It was around +15%.
When I lit it up, the BP kept fizzing out, and needed lighting up multiple times.

[darkfang77]

Results of the Magnesium Flare.
I thought it would be nice to post the results of the flare to show the effectiveness of the formula: Mg 60% KNO3 30% and 10% Charcoal + 5-10% Sulphur.

I used approximately 20g of the composition inside a 1" diametre fountain tube (unchoked), the length of the composition inside the tube is approximately 3". I set light to a small sample to see the effects. I have no decent camera which would give the effect justice so I am describing it.

The sample (approx 0.7g) was difficult to ignite at first but after some preserverance with a lighter, fuse, BP primer and paper, I managed to light it. The effects was arguably similar to flash powder, althought the burn rate was slower, the distinctive flash of the sample had a similar effect to flash powder (70% KClO4, 30% Al), there was a strong white residue and the sample spat white MgO.

The 20g flare was unchoked, had a bottom plug of kitty litter and was made of card rolled two-three times.
The flare would not light using Visco Fuse, and I resorted to use a primer of (50% KNO3, 25% sulphur and 25% sugar), the sugar burning partially blocked the opening of the flare, and I think that this enhanced the effects of the flare.

Why? After the primer burned, the 20g of flare composition started off, the light was overwhelming, even from a good 25ft away.
It looked like a white light fountain, with white sparks reaching up to 4ft. The flare lasted approx 10-15 secs.
This was done in the afternoon, and I think that the flare would have been more stronger at night.
The smoke from the flare was intense at first, but died down around about 6 secs in, to smaller plumes of smoke.
The sound of the flare was amazing, there was a strong distinctive roaring sound which reminded me of a furnace or a extremely large fire, possibly caused by the blocked opening, at one point the roar was so loud I was almost afraid it would explode, fortunately it did not, and it was made of paper anyway, so there would be no hazard.
This was a great result, and this composition I am jotting down into my memory.

I think this flare is definitely unholdable for any purposes due to the large amounts of white hot magnesium raining down from the flare. And suits as more of a fountain.

If anyone is reading this, does anyone care to answer some of these questions:

• Would a larger amount of comp enhance the height and duration of the sparks and flare? And would this possible increase the hazard of it rupturing midway?
  
• Is this composition ideal? Any way I could increase ignitablity without using a primer? More sulphur? Or more charcoal?
• What would happen if I used a more finer magnesium, the mesh I had was approz 30-40 mesh, what would be the result of using meshs such as 100-200?

If this post is inappropriate, please remove.

[seymour]

The composition is certainly not ideal, since I came up with it on the spot, and all 'draft' compositions, as it could be described, can be tweaked to improve things.

However, I'm pleased that it was satisfactory.

The Mg raining down while burning does not surprise me, since the powder was not very fine. So if you used finer Magnesium, the flare would burn much more cleanly (it should not be hard to eliminate residue completely, and only have smoke and gasses produced). Using a finer powder would also increase the burn speed, possibly quite dramatically.

Using a larger quantity of composition will have different effects depending on 'how you use it'. A flare of the same diameter, but longer, will as I probably don't need to point out, burn for a longer time, with the same flame (unless the burned paper starts disturbing it). A wider tube would increase the flame size and height. More magnesium would be burning in the air at any point in time

There is always a larger risk of any tube loaded with composition to malfunction if it is bigger, and the longer the composition is burning, the more likely it is to burn through the casing. However if it is unchoked, and fairly well consolidated, the worst likely malfunction is the tube burning away as it burns. I'm sure you know what I mean that in the fierce glare of the Magnesium flame, a small flame from burning paper will have a negligible effect on what it looks like.

As for making it light more easily, finer Magnesium will help hugely. With that, you will probably no longer have ignition problems (though you will also have increased sensitivity, and increased corrosion of the Mg).

In the mean time, you might want to try replacing all the Charcoal, Sulfur, and some of the Potassium nitrate with Black Powder mill dust.

Perhaps

Mg 60
Potassium nitrate 20
Black powder 20

If this does not light, then you can either:

-Keep adding more black powder until it reliably lights, (though the intensity of the flame may be slightly less)

-As previously said, using finer Magnesium.

-Or keep priming it. One layer of 50/50 flare comp/BP should easily light it, and easily be lit by a fuse, and only needs to be a few mm thick.

I would not feel comfortable using the prime you used and storing the flares for more than a few hours, since Potassium nitrate and sugar absorbs water and becomes damp far more than you'd expect from two negligibly hygroscopic chemicals, and many, if not most accidental ignitions involving Magnesium occur because the mix became damp.

Hope this helps!

Peace

[darkfang77]

Yes, I have understood what you have said there, and I will take these into consideration.
I don't really want to use a finer magnesium, although I might need it in the future, I like a more longer-burning flare, and although the burning Magnesium did bore a few black holes in a wooden chair, I found the effect somehow satisfying. Finer magnesium is somewhat more expensive, however.

I do wonder why commercially available flares/gerbs do not produce smoke though.
Once I went to a restaurant where they served birthday cakes with some sort of gerb (spat short lived sparks) stuck in, I was quite astounded as to how they managed to produce a few wisps of smoke and no smell whatsoever.

I think that, although you have said that the thickness of the tube for the flare is not important, I think in reality, it is very, very important. During my third flare, I had a two layer card for the tube and mid-way through the flare, the flare blew out sideways, in a not so dramatic way, the sparks had ruptured one side of the flare faster than the other, making a failed flare . A 3-5 layer will be used next time.

I do understand the risks of a hydroscopic mixture (50% KNO3/Sugar), but I used the flares less than a hour of making it, the priming mixture I used was made as soon as I was ready to light the flare, I will use a different primer next time.

I am very low on homemade charcoal powder, so I currently don't have enough of the stuff to make the formula you mentioned. I will make a few more original formula flares, then start putting together an order for my next batch of pyro chems, (Barium nitrate is a must, and so is some binder, and strontium).

What's the cheapest people have bought barium nitrate here? My supplier is supplying at £4.50/ 250 grams.

Thanks a lot Seymour!

Edit:

I am also trying one of Weingart's formula for comparison:

the formula is:

Potassium Perchlorate 8 parts
Aluminium Powder 3 parts
Flour 1 parts

Edited by darkfang77, 31 August 2010 - 04:13 PM.

[dr thrust]

not familiar with that formula, you says its weingart?,
im glad you had some success, but it sounds like you made more of a fountain that a flare, consider oils/Vaseline to control the burn rate

[darkfang77]

not familiar with that formula, you says its weingart?,
im glad you had some success, but it sounds like you made more of a fountain that a flare, consider oils/Vaseline to control the burn rate

It was in the 2nd revised book, not exactly sure whether it is Weingart's own or not. That formula (8 parts KClO4...) was quite good, I didn't use the same amount of the other formula so I can't make a comparison in terms of sound or smoke. But the sparks were bright but short lived, not very high, sparks were pure white, quite fast burning, the height of the sparks were short (around 6 inches.) Unfortunately, the thing about these great pyrotechnicians is that they use, not only the best materials, but the most expensive materials. Perchlorate is another of my shortages now , down to approx 15g left. Aluminium powder I seem to strangely have plenty of .

What else was there? Oh yes,

Made another magnesium flare, the one seymour put forward, I thought I could make a little more, total weight of composition was approx 34g, never again am I making another of those with a comp. weight of more than 15g. I live in the city, I have a big yard, but enclosed with lots of buildings, when I lit this flare, I was hoping it would be short-lived and not that noticeable. But then, the flare lasted a long time, not actually a long time, but too long for it to probably go un noticed. Light was considerably more than the previous ones, and gave out a lot more smoke than the previous ones, and I am not talking relative to the previous sizes, I mean there was actually a lot of smoke, adding the fact that the flare highlighted the smoke, I was afraid someone would call the cops, or something similar.

A lesson well learned, if I ever decide to continue this hobby in my next batch of pyro chems, I am sticking to something more... discreet, surely I can't go wrong with sparklers??

Another question, say I made a flare and used it, lots of noticeable smoke, but no long term effects (i.e gone 1> min later), would anyone be able to sue, complain or otherwise contact the authorities about it?

Second, what is, your in opinion, the most discreet/unsueable time to use these sort of things?

[dr thrust]

lol i hear you there buddy, the most discrete times,..around the 5th nov and new years eve
alternatively ive tested small flares gerbs ect under the guise of a summer barbecue/firework party.
ive tested the odd star( even these can make a hell of a lot of smoke!)in my back yard other than that its a trip out to a field late at night.
don't think you'll get many complaints, its loud bangs that get up peoples noses