823 replies to this topic

[Potassium chlorate]

I agree with the statement that 70/30 KClO4/Al is the "optimate" in both safety and performance.

The strongest perchlorate-based flash, however, is probably the "US Army" formula:

64% KClO4
22.5% Al (Dark pyro or German Black)
10% S
3.5% Sb2S3

Some variations are:

66.7% KClO4
25% Al (German Black) or Mg
8.3% Sb2S3

61.5% KClO4
23 % Al (German Black) or Mg
15.5% Sb2S3

I have only tried the "Shimizu" formula with sulphur, though:

64% KClO4
23% Al (German Black)
13% S

I must say that even this is considerably more powerful than the 70/30 KClO4/Al, at least if you make several grams (which isn't recommended to inexperienced people, of course).

I think the same must be said about KClO3 based formulas: that smaller amounts don't perform much better than KClO4 based. I've never made more than a gram of KClO3 based flash, though.

For the mixing I think the safest method is to put the ingredients in the container (card board tube or soft plastic film cannister), put on lid and fuse and mix it by carefully turning the container round, round for several minutes. To get a more intimate mix, however, the diaper method should be used.

Edited by Pyroswede, 16 October 2008 - 01:57 PM.

[portfire]

For the mixing I think the safest method is to put the ingredients in the container (card board tube or soft plastic film cannister), put on lid and fuse and mix it by carefully turning the container round, round for several minutes.

Does one have a death wish?

The formulas you posted are HIGHLY DANGEROUS and should NOT be attempted by anyone IMO..Flash is dangerous and adding any compound containing Sulphur just makes the composition extremely more sensetive .

I hate to be harsh, but if you ues this method and think it's the safest, then you have a lot to learn

Edited by portfire, 16 October 2008 - 07:25 PM.

[wjames]

agreed - that stuff is silly.

in the past week, ive tested my flash powder for safety.

The ONLY flash comp. i make is KN03/Mg 50:50. 400 mesh (both) mixed in paper cups.....3G at a time ( MAX)

I can't see why you would want anything more powerfull.

I've also tested it...Static, pressure, striking against various items ( wood, metal, ceramic, steel to steel, steel to alloy. in most combinations i can think off) only ever tested .2 g at a time.....all the impact tests were from 1.5m. ive also tested it against being contaminated...with various chemicals.

Ive heated it to 60 degrees centigrade....for 10 minutes, in an oven. again, failed to ignite.
Ive done all the tests with both very very dry comps. and fairly humid comps

It also, unlike some flash powders....Doesnt always instantly ignite from a naked flame.....little would you believe.....i'll try getting a video of this.


Having said this.....i WILL stress......Just because it didnt ignite for me, under these circumstances, it DOES NOT mean its safe, by ANY means.

I Always treat flash powder with the upper most regard. Even although i couldnt get it to ignite under certain circumstances, i still use "lots" of protection....anti-static tools(yip, i earth my spoon) anti static storage containers....AS pads, wrist band......i wear the right overalls....And, although you might think its OTT.....a NATO s10 respirator. Inhaled Mag powder isnt nice.....ever blown your nose and seen black powder...well....you'd be suprised how much of that gets into your lungs !

[Potassium chlorate]

Does one have a death wish?

The formulas you posted are HIGHLY DANGEROUS and should NOT be attempted by anyone IMO..Flash is dangerous and adding any compound containing Sulphur just makes the composition extremely more sensetive .

I hate to be harsh, but if you ues this method and think it's the safest, then you have a lot to learn

I didn't write "shake it"; I wrote "carefully turning it round, round". I should have added "preferrably on a stick at least 2 m long". There's still a risk for ignition through friction between the particles or reaction between the sulphur and the perchlorate, but the static electricity risk is eliminated as well as the risk when you put the mix in the container after you've diapered it.

Of course sulphur and/or antimony(III)sulphide makes it stronger. Why would someone like Shimizu say that and why would the US Army use it, if it weren't stronger than sulphurless flash?

And I did stress the risk with it.

And I've done this several hundreds of times.

Edited by Pyroswede, 16 October 2008 - 09:55 PM.

[dr thrust]

wrong! the static risk is not eliminated at all, the fact its got sulfur in it makes it super static, impact sensitive, also cant really see the need for super hot flash, in pyro 70/30 is just fine

[digger]

wrong! the static risk is not eliminated at all, the fact its got sulfur in it makes it super static, impact sensitive, also cant really see the need for super hot flash, in pyro 70/30 is just fine

I agree. In fact in most cases flash is not even needed at all. It is possible to make some pretty fast whistle powders, Salicylate whistle is only slightly slower than flash and far more forgiving.

The only need for flash is in ariel salutes, and the desired effect can easily be obtained with 70:30 without resorting to more sensitive mixtures. At least it is possible to mix more than a couple of grams without it being self confining. So in the event of an accident wearing the appropriate PPE you will get away with it rather than losing bits of body.

[wjames]

At least it is possible to mix more than a couple of grams without it being self confining. So in the event of an accident wearing the appropriate PPE you will get away with it rather than losing bits of body.

PPE needs to include a blast proof face mask in my opinion....at the minimum a pair of shatter proof goggles. NOT glasses.

Edited by wjames, 16 October 2008 - 11:05 PM.

[Potassium chlorate]

I think that if you use German Black aluminium, it doesn't matter how much protection you have if you make more than a few grams, even withouth sulphur/sulphides. It will virtually detonate anyway. The same goes for uncoated magnesium (with KClO4). Even some milligrams go "bang".

Salutes are very primitive and easily made but very impressive. 10 grams will be heard several kilometers away.

The infamous M-80 (the real stuff) contained perchlorate-based flash. That kind of firecracker is still legally available in Austria and Switzerland.

It might be childish, but I think firecrackers and salutes are fireworks as well, even if they're banned in several countries.

Edited by Pyroswede, 16 October 2008 - 11:07 PM.

[digger]

I think that if you use German Black aluminium, it doesn't matter how much protection you have if you make more than a few grams, even withouth sulphur/sulphides. It will virtually detonate anyway. The same goes for uncoated magnesium (with KClO4). Even some milligrams go "bang".

Salutes are very primitive and easily made but very impressive. 10 grams will be heard several kilometers away.

The infamous M-80 (the real stuff) contained perchlorate-based flash. That kind of firecracker is still legally available in Austria and Switzerland.

It might be childish, but I think firecrackers and salutes are fireworks as well, even if they're banned in several countries.

I think will find that there is a significant difference in the self confining weights. I will have to look up the exact weight for 70:30 in the books, but I believe it can be more than 10 grams. If you are mixing more than this then nothing will save you if you have an accident in close proximity to it.

Right thats it for me on the subject of flash, not a topic I generally like discussing due to the fact it is of limited interest compared with actually having the skill to put things together that don't just go b**g, which is easy to do.

[Potassium chlorate]

I think will find that there is a significant difference in the self confining weights. I will have to look up the exact weight for 70:30 in the books, but I believe it can be more than 10 grams. If you are mixing more than this then nothing will save you if you have an accident in close proximity to it.

Right thats it for me on the subject of flash, not a topic I generally like discussing due to the fact it is of limited interest compared with actually having the skill to put things together that don't just go b**g, which is easy to do.

Have you seen the guys on United Nuclear mixing 100 grams of 70:30 in a ziploc bag by shaking it? They didn't wear any protection at all, not even gloves, and they're licensed pyrotechnicians!

I know that >35 grams the noise of the salute will not be considerably higher, at least not for the human ear. That's when it's in a soft plastic film cannister. The limit where it confines itself even as a loose powder in open air might be somewhere around there.

[wjames]

It might be childish, but I think firecrackers and salutes are fireworks as well, even if they're banned in several countries.

were the first ever fireworks not indeed firecrackers...."Placing gun powder into bamboo stalks and then throwing them onto a fire to be ignited produced a louder and more powerful bang; hence the firecracker was born" ( i love google )


people call it guy fawkes night...because of him trying to make a big bang.........shame the chinese were doing it a 1000 years earlier !

[wjames]

Have you seen the guys on United Nuclear mixing 100 grams of 70:30 in a ziploc bag by shaking it? They didn't wear any protection at all, not even gloves, and they're licensed pyrotechnicians!

they're not wearing gloves for a reason....

at 100 grams....gloves wont help....as, if it went off, your hands would no longer be attached to your arms....they will be some 50 metres away...unlinke your torso and legs....they landed only 40 metres away.

[Potassium chlorate]

were the first ever fireworks not indeed firecrackers...."Placing gun powder into bamboo stalks and then throwing them onto a fire to be ignited produced a louder and more powerful bang; hence the firecracker was born" ( i love google )


people call it guy fawkes night...because of him trying to make a big bang.........shame the chinese were doing it a 1000 years earlier !

When I was a child we always bought a lot of firecrackers for Easter (yes, we have fireworks on Easter in some parts of Sweden) and New Years Eve. We had fun with them on daytime, unlike the rest of the fireworks. There were "ettöres" and "treöres" ("öre" is 1/100 of a Swedish Krona), Russian Crackers, Mini China and China Crackers. Ettöres and treöres contained just a few milligrams of BP, while Russian Crackers held 0.3 grams, Mini China 0.5 grams and China 0.8 grams. They were all banned in 2002.

[Potassium chlorate]

they're not wearing gloves for a reason....

at 100 grams....gloves wont help....as, if it went off, your hands would no longer be attached to your arms....they will be some 50 metres away...unlinke your torso and legs....they landed only 40 metres away.

I know. I have made even more than that when I was younger. I actually think surviving an accident with flash would be worse than being killed in one. The damages if you survive 10-20-30 grams must be horrible...

[wjames]

both excellent comments.

i knew swedes loved their firecrackers......theyre still legal in most of eastern block are they not ???? i.e poland etc.

i think the whole problem with them came about from youths abusing fireworks...same as "binge drinking" and the like.

Perhaps, after these 40 pages, someone should write a decent thread, as a stick...simply titled " Flash Powder Safety"

Edited by wjames, 16 October 2008 - 11:58 PM.