633 replies to this topic

[Potassium chlorate]

Don't all nitrates absorb water more or less, even if the ammonium, sodium and strontium salts do it in the extreme?

[digger]

Don't all nitrates absorb water more or less, even if the ammonium, sodium and strontium salts do it in the extreme?

Yep, but this mix gives a significant rise in moisture absorbtion. The poswer will be physically wet if left out for 12 hours (OK it may not be in the desert).

[pyrotechnist]

OK tried even more tests with pot nitrate, pot tartrate and sulphur and have yet to get a reasonable result. I have tried 75/15/10 mix of kno3, tartrate, sulphur and 60/30/10 these mixes merely burned slowly with a small flame producing small nice branching sparks. The next mix was 50/30/20 which just produced little pops and kept going out. So I thought sack this and tried perc, tartrate, sulphur in 70/20/10 which was reasonable and pretty energetic and 60/30/10 which didn't really light well. So does anyone have any suggestions?

[vaslop2005]

iron oxide (or any other) catalyst? or 2% magnesium maybe?

but if its going to be feasible, then its got to be cheap.

[MDH]

No, because his straight 5-3-2 mixture should be burning fairly well (not necessarily very fast, but with a large flame envelope). Watch this space - I will have a videos.

[Potassium chlorate]

The ideal BP substitute would be YP -- yellow powder:

potassium nitrate 55
potassium carbonate 27
sulfur 18

Though it has one drawback that is impossible to overcome: it only works when molten together and heated up. It doesn't catch fire from a fuse.

[Jerronimo]

The ideal BP substitute would be YP -- yellow powder:

potassium nitrate 55
potassium carbonate 27
sulfur 18

Though it has one drawback that is impossible to overcome: it only works when molten together and heated up. It doesn't catch fire from a fuse.

I strongly advice you not to make this compound, it will detonate when heated to long.
Also it deflagtates way to fast to be usable as a blackpowder substitute.
Shelflife will be a couple of days at best as it's ability to draw moisture from the air makes it useless.

There is no ''easy'' substitute for black powder, if there was we would already be using it.

[Potassium chlorate]

I strongly advice you not to make this compound, it will detonate when heated to long.
Also it deflagtates way to fast to be usable as a blackpowder substitute.
Shelflife will be a couple of days at best as it's ability to draw moisture from the air makes it useless.

There is no ''easy'' substitute for black powder, if there was we would already be using it.

I know that it detonates when heated; that's why I stress that it cannot be lit properly with a fuse.

I'm not that sure about the fast deflagration, though. I have used "weak" flash with magnesium and barium or potassium nitrate to lift 2" shells, before I had a proper ball mill. It can't possibly be "stronger" than nitrate flash. The estimation from laboratory tests is that it is 3 times "stronger" than BP, though I don't know in which respect; burning, gas volume, brisance etc.

[pyrotechnist]

Try potassium perc, potassium nitrate, potassium sorbate, sulphur in 20/50/20/10 ratios and when properly incorporated and fine it will burn very fast though trying to keep it dry is a different matter!

[Mumbles]

Strontium nitrate, when pure, actually isn't all that hygroscopic. The reason the orange absorbed so much water is because you used an inferior formula. The sodium oxalate and strontium nitrate will react almost instantly when exposed to humidity or water to form very insoluble strontium oxalate and sodium nitrate. I've personally taken to barium nitrate and strontium nitrate mixes to form yellows and oranges. Cryolite and potentially sodium benzoate are about the only sodium sources I know of that will work well with barium and strontium nitrates.

[Potassium chlorate]

Hm, I mixed strontium nitrate with cryolite, although within few hours it was very wet. The burn rate was about 10 times slower than when it was newly mixed.

[Mumbles]

At least in the US there was some cryolite going around that contaminated with sodium fluoride. That would cause the problem you mentioned. Have you ever tried to add some to water and test the pH? It should test perfectly neutral. A basic level indicated some sort of contamination. Natural mineral sources are more likely to be contaminated than synthetic product.

Maybe I shouldn't have said strontium nitrate. I have no first hand knowledge of working with that combination. I do use barium nitrate + cryolite for a lime star I like though, and it works just fine.

I just confused myself. The orange star I like uses strontium nitrate + sodium oxalate, and it works just fine.

[Potassium chlorate]

The cryolite is synthetic but ceramic/pottery grade. Though I live pretty close to the sea, so the air is humid here most of the year except on really cold or really hot days.

[Mnemotron]

I would say try these:

KClO3, 55
CuCl2, 23
PVC, 10
Shellac, 7
Dextrin, 5

KClO3, 57
BaCl2, 20
Shellac, 8
PVC, 10
Dextrin, 5

Only try them in small amounts at first if you scale is capable of measuring in 1/10 or 1/100 of a gram. Raise or lower the fuel value until you recieve a preferable burn rate or light output. Raise the KClO3 for a higher light output. Once you've found the right composition, make a larger amount.

It would help if you told me what chemicals you have so I'm not troubleshooting my way through this...

MHD do you think that the formula you give me for BaCl2 burn hotter enough for emitting green light?

[MDH]

I'm not certain, I've only worked with copper chloride - but I can tell you compositions with chlorate, shellac and PVC burn quite hotly. A barium chloride variant will have to be played with to work properly.

With that being said, how has your experience been with copper chloride? I've had lovely experiences using it in stars with quite a number of fuels.