epsom salt flash powder

[artificier]

hey friend I will find in a pyro site : JPYRO a nice formula to make

flash powder out of epsom salt !!

 

this is the info :

 

At the Eleventh International Pyrotechnics Seminar, 1986, in Vail, Colorado, I reported on a study of pyrotechnic mixtures with a theme, "A Concept and the Use of Negative Explosives". A further study has been continued on the same subject as before. In the former report it was known that magnesium sulfate/magnesium mixture detonates on heating.The chemical reaction of the magnesium sulfate/magnesium mixture on detonation is thought to be:

 

MgSO4 + 4 Mg ® MgS + 4 MgO + 353 kcal

 

From several experiments following results were obtained:

(1) The intensity of the explosive noise from the magnesium sulfate/magnesium mixture is almost the same as that from the ordinary aluminum mixture when the weight of the charge of the former is two or two and a half times as large as that of the latter.

(2) The magnesium sulfate/magnesium mixture is far more safe on handling than the ordinary aluminum mixture. It was proved by an iron ball dropping test and a fire propagation test.

(3) The tone quality of the noise from the magnesium sulfate/magnesium mixture is mild and superior than that from the ordinary aluminum mixture.

 

this is the info, but the problem, I dont have the ratio of magnesium sulphate/magnesium.

[Crazy Swede]

Yes you have!

 

The formula indicates 1 mole magnesium sulphate to 4 moles of magnesium powder. So, what's the trouble calculating the amounts from that?

[artificier]

euh I dont know but thank for your ratio:

 

45% fine magnesium powder

55% magnesium sulphate

[teknix]

If you have 4 moles Mg with a MW of 24.31g/mol you multiply the 4 moles by the MW of 24.31g/mol to get 97.24g Mg. Do the same for the MgSO4 (1 mole X 120.37g/mol MW) and you get 120.37g MgSO4. Now add them up and you get 217.61g total mix. Now divide each component weight into this to get a percentage. 97.24/217.16 = 45% and 120.37/217.16 = 55%

 

Mg – 45%

MgSO4 – 55%

 

Edit:

 

Hahaha sorry mumbles I was bored and wanted to do a little math...I couldn't help myself.

[Mumbles]

Yep, you should try that ratio you have out. Let us know when it doesn't work and I will tell you your two main mistakes.

 

 

Awwwww, teknix, let him learn from his own mistakes. C'mon The 4:1 mass mixture would never burn in the first place so there is no harm.

[Blaf]

C'mon guys, would someone tell us (I'm sure there are others here watching this too) whether this flash comp works at all or not....

 

Blaf

[TheSidewinder]

Mumbles just gave you the answer, albeit in a backhand way....

 

M

[Pyrohawk]

I was bored so I just tried it.... Nothing happened....its sizzled a little then nothing. I couldn't get it to light. But then I read at the first post that this stuff is supposed to detonate not deflagrate. Nothing seems to happen with just a fuse but I had to try it. Someone who has a primary made should attempt to detonate it and see if it works....

 

Then again it could be just that my scales are bad or its damp or something.... I don't feel like messing with it anymore because even if it does work its not worth the effort to me! So if anyone else wants to know go ahead and try it.

[Rogue Chemist]

Reminds me of the CaSO4/Al mix...

 

I hope you were not using plain epsom salts, the anhydrous MgSO4 is needed here, which also complicates storage of the mix as it tends to absorb water from the air.

 

If it is like the CaSO4/Al mix, Mg ribbon will be needed to get it going.

[teknix]

Yeah I've read that it works but you need something with a very high heat to set it off and regular fuse just isnt going to cut it. Also yea make sure your using anhydrous MgSO4. The stuff really isn't worth it though and isn't very practical.

[aquaman]

Teknix do you think a thermite type fuse would be hot enough?

[Pyrohawk]

Yeah, I powdered some epsom salt with my coffee grinder. Then I spread it on a piece of foil and baked it on 500F till it was dry and crumbly to get rid of the water. Repowdered it because it got all caky and then mixed.

[iv81]

Hi all, I just registered so I can reply to this topic.

 

Anyway, I have experiemnted in the past with powdered epsom salt and indeed did have managed to set it off. Used a butane torch and mixed it in with some fine aluminum flake (indian black) around 65/35 mix. It took about 30-50 seconds for it to go off tho. The flash it produced was a bit more blinding than 70/30 perch mix. Hope that's useful.

[shadopyro]

hmmm...this seems very similar to the barium sulphate flash powder mentioned in another post i made (" best flash powder"), the barium flash powder is mentioned as being rather powerful, more stable than normal 70/30. but the description that i read reported that the powder is easy to ignite. Though it IS barium sulphate compared to magnesium sulphate, as the barium sulphate will be able to give up ts oxygen to the fuel easier than magnesium sulphate.

[Douchermann]

Try to light it with some Mg ribbon sometime, or making a prime for it like a 50/50 of the MgSO4 flash with a really hot burning flash like KNO3:Mg followed by another layer of pure KNO3:Mg flash.

 

Or maybe its just not good on its own, maybe if its mixed with another flashpowder it would be easier. Only be worth it if it produces more gas volume than normal flashpowders though.

[artificier]

hmm nice idea ! but MGSO4 need a strong primer to ignite ? like thermite ?

[pa_pyro]

hmm...magnesium ribbon to light the thermite to light the MgSO4/al...

 

Just to clarify is the ratio 65/35 MgSO4/al or al/MgSO4?

[artificier]

i will buy MgSO4 and i will try to set off a mixture of MgSO4/Mg and i show a video of it !

[shadopyro]

Dont forget to bake it, as i still need to bake some of my plaster of paris (Caso4 i believe). Though when unbaked and still retaining its waters of hydration it burnt like a "not so hot thermite". Think i'll try this in a rocket comp as soon as i get the bottle rocket kit (less material used in a bottle rocket!)

[artificier]

but MgSO4 its look like a salt,i will found this product in bulk quantity in a wal-mart.and its for bath relaxaxion purpose. You are sure to bake epsom salt ? what the time and the temperature i bake the salt ?

[shadopyro]

Your right it is dry to the eye, but it has waters of hydration around the molecules of MgSO4. This must be driven off.

 

I'd say at something like 150 C for about 20 mins in the oven, the temperature in an oven shouldnt affect it much as it its melting point is rather high.

[artificier]

okay thank i try this next week and i show pic and vid !

[Mumbles]

If it's epsom salt it contains 7 waters of hydration per molecule. 20 minutes won't cut it by the way. I'd say 150C for two to three hours to ensure it is dry. The melting point is about 56 degrees by the way for the hydrate. This is just water of hydration coming off and dissolving the salt. You're probably going to have a big cake of MgSO4 by the time you're done.

[shadopyro]

Oh! Sorry for the mistake!

Wow 2 hours....

[artificier]

for the moment i dont have some money to buy epsom salt but i begin to shave my Mg firestarter !