15 replies to this topic

[grimmers87]

Hi all.

Now i know that everything that we know today was all down to a process of illimination (or trial and error), but I was wondering if anybody knows any formulas for anything really unusual or spectacula? Prefferably your own derived through the above process. I am also interested to know what people believe is the best, im not looking for a genral census, more an indivdual this is what I preffer!!!

Any answers would be greatly appreciated.

THANK YOU

^_Grimmers87

[seymour]

Hi all.

Now i know that everything that we know today was all down to a process of illimination (or trial and error), but I was wondering if anybody knows any formulas for anything really unusual or spectacula? Prefferably your own derived through the above process. I am also interested to know what people believe is the best, im not looking for a genral census, more an indivdual this is what I preffer!!!

Any answers would be greatly appreciated.

THANK YOU

^_Grimmers87

Not everything is trial and error in this hobby/industry. With experience and reading one gains an intimate understanding of the chemicals used. We intelectually know that adding Chrome oxide to a perchlorate composition will speed it up because we are aware that it is a catalyst, and because we know that one mol of Potassium perchlorate contains four mols of oxygen atoms, that it will burn producing mostly Carbon dioxide with two mols of carbon atoms, and primarily Carbon monoxide if one mol of Potassium perchlorate is burned with four mols of carbon.

That said, trial and error is present. Many effects, such as streamers rely on the ratios not being correct for completion of the initial chemical reaction, and there are often unforseen reactions, which is not surprising when you have a mixture of six chemicals containing twelve elements between them, in varying state of oxidisation!

Personally, I do not like the idea of saying something is the best, and I do not have a favourite composition. However there is usually a mix that I am quite pleased with that I've made recently.

At the moment this is the following..

Ammonium perchlorate 72%
Polyurethane binder 16%
Copper (II) oxide 10%
Aluminium (indian dark) 2%

I imagine the rocketry minded people would recognise this as a variation of APCP that would result in a cato if used in their precious hardware. Firework minded people would think of it as an expensive extravagance. I think of it as my latest go-getters that took a fair bit of time to make and raided some of my best chemicals.

However I do not like this any more than Shimizu's tigertail, which by our standards is a very modest formula:

Potassium nitrate 44%
Chartcoal 44%
Sulfur 6%
Binder (SGRS, Dextrin, CMC, GA) 6%

http://pyroguide.com...tail_mayhem.jpg


Now I have answered your question, you must answer mine

What do you want this for? Purely curiosity or do you have some project??

Edited by seymour, 22 July 2009 - 06:06 AM.

[grimmers87]

I am interested purely for curiosities sake, but it would be handy if I could pick up something I could use myself.

Thank you for sharing your knowledge.

[pyrotrev]

Seymour, may I ask what kind of polyurethane you used please? I'm interested in using it as a star binder, but there's a bewildering choice of different types available.

[seymour]

I'm using "Barnes flexicast". I am not sure what the components are chemically. I know about the overwhelming choice! The stuff I have is actually unideal. I have it because it expanded too much for my rockery friend to use in his EX rockets, so he gave it to me.

I'm afraid that I do not know what you should look for with any detail. However I'm sure there are people near you who make their own APCP for rockets, and would be willing to direct you towards where they get their binder, and what particular one is best.

[sir steve]

Hi all.

Now i know that everything that we know today was all down to a process of illimination (or trial and error), but I was wondering if anybody knows any formulas for anything really unusual or spectacula? Prefferably your own derived through the above process. I am also interested to know what people believe is the best, im not looking for a genral census, more an indivdual this is what I preffer!!!

Any answers would be greatly appreciated.

THANK YOU

^_Grimmers87

With experiance and reading you can knock up about any effect you want. I have to say a lot of published formula are rubbish.
The problem comes with charcoal and glitter effects that are so variable. I think the usual proble is the charcoal should be
finer than a lot of people say.

Steve

[Potassium chlorate]

90% barium chlorate and 10% shellac. You dissolve 1 part shellac in 8 parts of warm alcohol and mix in the barium chlorate. When the mix forms kind of a "sediment" in the alcohol, you simply pour off the exceed alcohol and put the composition in a toilet paper roll. Put in a 2 or 3 mm Visco fuse and let it dry for at least 24 hrs (a 100 gram batch). Then you have a very nice green Bengal fire. I have described this before in another thread, but if you're into Bengal fires and can get hold of barium chlorate, this is a very nice and simple one.

[a_bab]

This green is the deepest I have seen; however, does anyone have something similar that doesn't use barium chlorate? A star composition that is deep green?

[Potassium chlorate]

I haven't tested this particular one myself, but I know from experience that potassium perchlorate and barium nitrate give a good green, although not as extremely good as barium chlorate:

Barium nitrate 28

Potassium perchlorate 48

Red gum 14

Parlon 5

Dextrin 5

Cut or roll.

[seymour]

I haven't tested this particular one myself, but I know from experience that potassium perchlorate and barium nitrate give a good green, although not as extremely good as barium chlorate:

Barium nitrate 28

Potassium perchlorate 48

Red gum 14

Parlon 5

Dextrin 5

Cut or roll.

Actually I find that Potassium acts as an impurity with green. I can only assume that the lilac spectrum pulls the green somewhat towards the white/yellow. While this is not serious enough to make such greens unusable, due to the fact that potassium is a weak emitter, it is worth thinking about.

If you want the deep, rich dark forest green, you will not have any luck without Barium chlorate. However if the tone of the green is not so important, and a rich grass-green is suitable, this is easy to get in compositions high in Barium nitrate and chlorine, with enough metal fuel to get the temperature high enough for the barium to emit efficiently. The finer this metal fuel is, the better the colour will be, as coarser metals dirty the flame.

Pyroswede you forgot to name the creator of the formula. It is a rounded version of the formula given by Shimizu in FAST, page 216. Having made it, I am sorry to inform you that it is not a good green. It was the first I ever made and I was not happy. In my opinion it contains far too much Potassium perchlorate, not enough Barium nitrate, is lacking in a metal fuel, and contains not nearly enough Parlon.

A better Green would certainly be J.A. Green Pill Box #2, MgAl, by John Albert.

Barium nitrate 60%
Magnalium (finer the better) 15%
Parlon 15%
Dextrin 10%


While the composition is designed as a pill box star, and certainly performs well in them, there is no reason it could not be cut or pumped, though I might suggest replacing half te dextrin with red gum if water is to be used to activate the dextrin. 10% would be enough to cause annoying stickeyness.

[a_bab]

My problem is that even before attemting to make a usable formula, I tried some of the little amount of barium chlorate I have and all the tested green formulas afterwards looked realy pale. Red is easy, but green is difficult.

On the thread lines, does anyone have some nice ammonium perchlorate formulas beside blue with PVC as chlorine donor?
My view about AP is:
- hard to ignite
- incompattible with KNO3, chlorates
+ burns slowly
+ burns clean

With these in mind, is really impractical to use a formula with AP exclusively as an oxidizer, unless blue. A good formula must look like Baechle's system. It can have both KP for ignitability and AP for slow, clearer burning, some hexamine for making the flame bigger, some organic AND metalic fuel, and obviously a flame colorant + chlorine donor.

With these in head, I kept experimenting, dreaming that I can make a "base" (oxidizers, fuel, chlorine donors) to wich I should add a certain amount of colorant and presto: star formula done. Everyone has access to different kind of chems, and everyone should adapt the formulas. It looks like although I did eventually make a base, the colours are not the best, at least for the geen. It's so annoying the green is elusive to me. Almost like blue.

Thanks for the tip concerning the metal fuel size in greens; I guess it applies to all the colours.

[Potassium chlorate]

a_bab, you got a PM.

[Potassium chlorate]

Actually I find that Potassium acts as an impurity with green. I can only assume that the lilac spectrum pulls the green somewhat towards the white/yellow. While this is not serious enough to make such greens unusable, due to the fact that potassium is a weak emitter, it is worth thinking about.

If you want the deep, rich dark forest green, you will not have any luck without Barium chlorate. However if the tone of the green is not so important, and a rich grass-green is suitable, this is easy to get in compositions high in Barium nitrate and chlorine, with enough metal fuel to get the temperature high enough for the barium to emit efficiently. The finer this metal fuel is, the better the colour will be, as coarser metals dirty the flame.

Pyroswede you forgot to name the creator of the formula. It is a rounded version of the formula given by Shimizu in FAST, page 216. Having made it, I am sorry to inform you that it is not a good green. It was the first I ever made and I was not happy. In my opinion it contains far too much Potassium perchlorate, not enough Barium nitrate, is lacking in a metal fuel, and contains not nearly enough Parlon.

A better Green would certainly be J.A. Green Pill Box #2, MgAl, by John Albert.

Barium nitrate 60%
Magnalium (finer the better) 15%
Parlon 15%
Dextrin 10%


While the composition is designed as a pill box star, and certainly performs well in them, there is no reason it could not be cut or pumped, though I might suggest replacing half te dextrin with red gum if water is to be used to activate the dextrin. 10% would be enough to cause annoying stickeyness.

The guys in the UK and Germany have great difficulties getting any chlorates and perchlorates at all. In Germany I think it's banned for private citizens. Here in Sweden they're legal, but barium chlorate is still hard to get. While most pyro chemicals here are free according to the law, most companies won't sell to private citizens.

[Creepin_pyro]

With these in head, I kept experimenting, dreaming that I can make a "base" (oxidizers, fuel, chlorine donors) to wich I should add a certain amount of colorant and presto: star formula done. Everyone has access to different kind of chems, and everyone should adapt the formulas. It looks like although I did eventually make a base, the colours are not the best, at least for the geen. It's so annoying the green is elusive to me. Almost like blue.

You really should look into the Baechle systems for this kind of thing...

[seymour]

My problem is that even before attemting to make a usable formula, I tried some of the little amount of barium chlorate I have and all the tested green formulas afterwards looked realy pale. Red is easy, but green is difficult.

On the thread lines, does anyone have some nice ammonium perchlorate formulas beside blue with PVC as chlorine donor?
My view about AP is:
- hard to ignite
- incompattible with KNO3, chlorates
+ burns slowly
+ burns clean

With these in mind, is really impractical to use a formula with AP exclusively as an oxidizer, unless blue. A good formula must look like Baechle's system. It can have both KP for ignitability and AP for slow, clearer burning, some hexamine for making the flame bigger, some organic AND metalic fuel, and obviously a flame colorant + chlorine donor.

With these in head, I kept experimenting, dreaming that I can make a "base" (oxidizers, fuel, chlorine donors) to wich I should add a certain amount of colorant and presto: star formula done. Everyone has access to different kind of chems, and everyone should adapt the formulas. It looks like although I did eventually make a base, the colours are not the best, at least for the geen. It's so annoying the green is elusive to me. Almost like blue.

Ammonium perchlorate, unlike Potassium perchlorate and Potassium chlorate releases it's chlorine completely as HCl. Because of this, when using it as an oxidiser, there is absolutely no need to add a second chlorine donor.

While I certainly agree that Ammonium perchlorate compositions burn cleanly, and tend to have a slower burn rate when compared to Potassium chlorate and Perchlorate, this is not always the case. The choice of fuel, catalysts present, and other variables in formulation can indeed produce Ammonium perchlorate formulas that burn very fiercely indeed.

Interestingly, while it is often thought that Ammonium poerchlorate compositions are hard to ignite and are easily extinhguished by high speeds, test by Shimizu found that the oxidiser is superior in both of these regards in comparison to Potassium perchlorate and Potassium chlorate when burned with a variety of organic fuels. I find this quite puzzling, and again, specific formulations will either reinforce popular steriotypes, or Shimizxu's results.

In my experience, the incompatability of the oxidiser with Potassium nitrate, and much more severely, Chlorates have been much easier to overcome than the reactivity with Magnalium.

While the idea behind a colour system with a base mix, requiring only small aditions to get a complete colour range sounds great, it is my opinion that it is a step towards simplicity, but equally a step away from quality. It is just an unavoidable fact that the different colours have different 'needs', resultimng in different formulas. For example, I would want no less than thirty per cent of Barium nitrate as a colouring donor for green, while that much Copper oxide in a formula would simply not work. While one could replace Barium nitrate with Strontium nitrate, the red will burn notisably slower than the green, and will require modification to get the burn rate and flame size to match. And if you are using Strontium carbonate, problems arise.

Besides that, the different emitting molecules each work best in quite different environments. While for a red it does not matter much if there is excess oxygen present, this will cause 'polution' in a blue, due to the red emission of copper oxide formed. Equally, temperature plays a large role. As it is well known, Copper requires lower temperatures in comparison to other colours to perform optimally. While it is not as big a difference as it is between Cu and the other emitters, Barium, Calcium, Sodium and Strontium all perform best at somewhat different temperatures.

To summarise my opinion, a unified colour system revolving ariound a simplified base mix may well work, but will do so at the cost of the quality of one or more of the colours. To get colours that each have colours tweaked for performance, and unified in burn rate, flame size, and as much as possible brightness, you cannot have them completely unified in their formnula bar-the colourant.

That said, if you want simplicity of manufacture first and foremost, ignore my ramble.