823 replies to this topic

[spanner]

Comercial Salutes are not tumbled in a sealed container, they are intermixed by air current in a grounded machine that prevent static build up.

I'm sure this varies among manufacturers- I recently read of a contractor who told of remotely tumbling M80-type salutes in a converted cement mixer. The compound was added a component at a time, the tumbling did the mixing.

[bigtonyicu]

I'm sure this varies among manufacturers- I recently read of a contractor who told of remotely tumbling M80-type salutes in a converted cement mixer. The compound was added a component at a time, the tumbling did the mixing.

I hope that's thing is behind an armor concrete wall,... because 8 oz is more then enough to shred that barel (doesn't have to be sealed). I personally don't know of any Country (maybe with the exception of China) that allows that kind of process. Most laws requires the emediat containment of the mixed loose powder. the air mixers are mornally attached to the assembaly line and packaged in the tubes simultaniously (fire cracker type production).

[spanner]

Most laws requires the emediat containment of the mixed loose powder. the air mixers are mornally attached to the assembaly line and packaged in the tubes simultaniously (fire cracker type production).

I'm not really following the containment reference, "containment" being what brings about an explosion (self-contained or otherwise) instead of deflagration.

The M80-type salutes were made here in the USA. The mixer was remotely operated and because this was (is?) a professionally licensed operation, I can only assume the laws were being followed. I'm 90% sure I read it at rec.pyro, might've been Lloyd Sponenburgh or Mike Swisher. The time frame is what I'm unsure of- what was legal years ago might not be, now.

As to firecracker manufacturing, the only video I've seen was of an elderly Chinese lady (in China) filling a gross at a time by hand. Rolled the tubes up into a large hexagonal shape, put the comp into them, gave them a "flip" to fill half way, then on to the next! Hell of a way to make a living... Probably larger manufacturers there and elsewhere utilize "air mixers".

Edited by spanner, 23 October 2008 - 08:19 PM.

[rr22]

I think "containment" in this context means the flash is placed A.S.A.P into the item being manufactured,
so as to not have loose comp. laying around.
I too recall the rec.pyro thread,i believe an open "cage" type mixer was mentioned.

The Rev. Lancaster has this to say;
"A measure of sieved free-flow oxidizer is placed in the tube first,followed by by a measure of metal powder,and the tubes are sealed.The filled tubes are then taken to a gentle tumbling machine,
which turns them end over end at the other side of a concrete barrier.The mixing is not as efficient,[as diaper method]but it works"*

I know a member of this forum remote tumbles salutes in a rock polisher,but the important bit is "remote".

This doesn't really impact on the advisability of hand tumbling,and specifically relates to Perchlorate/metal comps,but I presume frequent detonations of product would have resulted in a safer method evolving in the trade.

*Principles and practise 4th.ed. page 262.

Edited by rr22, 23 October 2008 - 10:37 PM.

[bigtonyicu]

Tumbling in tubes is a whole new ball park, even is something was to go wrong chances are only one would go off, damage several (if not all the others), but with the nature of flash powder makes it very unlikely that the powder from the other tubes would go off; plus the powder being mixed in a smaller container also restricts the friction (hence static) and will much less likely to ignite.

I can see that process being used for Nitrate + Al + S and for KClO4 + Al flashes; but would highly recommend that no flash containing Sb2S3 be tumbled, it use to be VERY common in Display salutes (creates a louder & deeper tone) but problems in handling has led to it being phased out.

[Potassium chlorate]

NEVER ever trust anything found on Youtube!!!!

And sulfur and Antimony Trisulfide are 2 VERY different beasts, Sulfur isn't conductive, Sb2S3 IS and to make it worst the shape of the grains are very thin needles with a very high resistance to electrical energy, so if mix vigorously and static forms, chances are that the Sb2O3 will carry most of the charge (Al2O3 has a higher resistance) and that means Very hot localized stops witch can lead to ignition...

Tumbling causes:
More friction = More electrical energy = More hot spots = WAY more danger

Like I said earlier in the thread: the "Shimizu" mix (I call i that, because he states that that's the most powerful mix obtainable with perchlorate and sulphur) is stronger than the 70:30, no doubt about it. I don't even have Sb2S3, though I will probably buy it sooner or later, since it's useful in many compositions. Then I will try to make batches of at most 1 gram flash with it and see if it improves the performance that much.

[Jerronimo]

Well, I do agree flash should be used and handled with great care.

BUT don't get to paranoid.
Kg quantities are used in fireworks factories every day.
Just look at those masleta's in Valencia spain, where once salute can hold a huge amount of powder, and all that stuff is made in Spain!
Saw some video's of a pre fire build up, and those guys were throwing bundles of finished salutes that were the size of a tennis ball around like they were empty.

Look at those huge Kg! bottom shot's the Maltese make, and that's KClO3 flash if I'm not mistaken!

And look at the Chinese, enormous amounts of firecrackers filled with flash are exported around the world every year, if this stuff is so shock and friction sensitive even when placed in a sealed cardboard container it would have resulted in many explosions and been banned decades ago.

Don't get me wrong here I don't say that you should ball mill the stuff, the diapeer method is the only one to use by a hobbyist .

The only flash I make is 4:1:1 KNO3/S/Al and actually like it better as a report formula.
Because of the slower deflagtation it creates more of a deep boom than a sharp crack.

[wjames]

The only flash I make is 4:1:1 KNO3/S/Al and actually like it better as a report formula.
Because of the slower deflagtation it creates more of a deep boom than a sharp crack.

im with you, i prefer a slightly slower flash, for a chest thumper..........I, however, don't like adding S into my flash, and so i stick to good old 50:50 KNO3:Mg...........its damn bright though.........gives a great report, and doesnt self contain until like 15G or so.....of which i never make ! i might need more than you for the same report, but its safer to make, in my opinion !

[portfire]

I think people need to be reminded just how dangerous flash is.

I've just dug this topic out started by 'BigBang' a while ago (hope you don't mind, I'll remove my post if you wish) AND PLEASE! don't go PM-ing him asking for the formula as I very much dought he'll give it anyone.

http://www.pyrosocie...hl=Flash powder

[Bonny]

im with you, i prefer a slightly slower flash, for a chest thumper..........I, however, don't like adding S into my flash, and so i stick to good old 50:50 KNO3:Mg...........its damn bright though.........gives a great report, and doesnt self contain until like 15G or so.....of which i never make ! i might need more than you for the same report, but its safer to make, in my opinion !

From what I read in your posts, you have very little knowledge and experience... I don't think you should be advising anyone on flash powder, or even making/using it yourself. I've been doing this for awhile, and I have read ALOT and I very rarely use any flash and definately don't recommend it to the inexperienced.

Edited by Bonny, 26 November 2008 - 03:51 PM.

[Richard H]

Magnesium brings a number of unique hazards and challenges. Not to be taken lightly. In a commercial setup, the risks during mixing and handling are controlled and reasonably small, but accidents can and do happen. Only recently a flash mixing workshed at a Spanish factory was involved in an explosion that claimed the lives of two respected men.

Just because the risks may be small, does not mean you should ever become complacent. Treat all compositions and processes involving them with respect.

[bigtonyicu]

I agree, Mg flash are un-needed, stupidly sensitive and dangerous, there's no need for them. get the right stuff and keep it safe you can get the same chest thump with Aluminum and KClO4. Magnesium is just too reactive for no reason.

[TCblastmaster]

A number of years ago I got some 2 micron Mg from Skylighter for experimenting with a flash comp. referred to by Shimizu as a 'negative ex*****ve'. It contains Mg/Mg SO4, the latter being in anhydrous form. It is considerably less sensitive but a salute needs 2-3 times more than if one were to use a perc.-based flash. I never mix Mg with a traditional oxidiser. When mixing I limit this stuff to small amounts and still use the diaper method (wearing PPE). Unfortunately I have mislaid the reference for the article but the comp is unexpectedly effective, if a little blinding. Nice deep report though.

The chemical equation given was theoretical and the (stoichiometric )ratios used as the starting point gave quite promising results. However I lost interest in my experiments to fine-tune its performance because being no longer able get the Mg it was pointless continuing. I am now using the remainder of my stock as the inner composition in my E-matches. It is excellent for this!

Has anyone else tried any of these 'safer' flash comps.?

TC

Edited by cooperman435, 28 November 2008 - 12:13 PM.

[spanner]

The information I have for Shimizu's Negative Explosive shows the Mg to be -80 mesh for green, orange, red, yellow and white. Another Negative Explosive listed was:
60.00% Magnesium (-60 mesh)
40.00% Magnesium sulfate, Anhydrous
Mix and granulate with nitrocellulose solution.

I made the orange and when lit unconfined it gave a bright yellow (more than orange) color. The speed was about that of whistle mix.

Shimizu comments that the explosive force is about 12% that of BP. I don't want to get OT with anything "explosive" here, so moderators please delete/move as you see fit.

One question- what are these comps used for?

Edited by spanner, 30 November 2008 - 05:37 AM.

[TCblastmaster]

The information I have for Shimizu's Negative Explosive shows the Mg to be -80 mesh for green, orange, red, yellow and white. Another Negative Explosive listed was:
60.00% Magnesium (-60 mesh)
40.00% Magnesium sulfate, Anhydrous
Mix and granulate with nitrocellulose solution.

I made the orange and when lit unconfined it gave a bright yellow (more than orange) color. The speed was about that of whistle mix.

Shimizu comments that the explosive force is about 12% that of BP. I don't want to get OT with anything "explosive" here, so moderators please delete/move as you see fit.

One question- what are these comps used for?

The latter comp is similar to the one I tried but the mesh size of Mg seems somewhat too large to produce the extremely energetic
reaction I obtained. It was marginally slower than whistle mix (which is very fast when properly made, far faster than BP) but I'm sure its performance could have been optimised by adjusting the ratio of Mg:MgSO4.
A comp with only 12% the force of BP suggests that what you are referring to is an entirely different beast and I'm not sure what it could be used for.

What is in the colour comps? Do you have a reference for the info?

TC