823 replies to this topic

[Phoenix]

I don't think that a BP break is too weak for a 2" shell. I used to use BP coated Rice Krispies mixed 50/50 by volume with the stars to break my 1-1/2" shells, but I now I fill the shell completely with stars, then shake polverone (made with mill dust, rather than green mix) into the gaps. Tightly spiked, either of these break charges would shatter the shell casing into small pieces and send the stars plenty far enough, with as round a break pattern as you'd expect from a shell this size. The second method just allows more stars to fit in the shell.

It is important that you get the spiking and other casing construction correctly suited to the break charge for it to work well though. I had a few blow out the end before I got the construction right, so they shattered rather than dumped the stars. Once you find a design that works using your materials, you can easily get (IMHO) very satisfactory results using only BP.

EDIT: Just thought, I make cylinder shells. If you are using ball shells, especially if they are plastic, then this may not apply. I have very little experience with ball shells, and none with plastic. There is and article on 1-3/4 paper ball shells on Passfire, which can be made using either a BP or KP break charge. The KP did give a rounder break, but the BP wasn't bad.

Edited by Phoenix, 09 October 2004 - 08:23 PM.

[Jerronimo]

Sorry, I just assumed that he used round shells, with a cylindrical shell it could work.

[Phoenix]

Yeah, I did the opposite and assumed cylinder shells. Having said that, I just watched the video of your 3" shell, and the break was definately better than mine (70mm), which are broken with plain BP on Rice Krispies. Nice work!

[adamw]

If you want something a --bit-- safer than a flash maroon try a can shell full of Lambetti (Saettines). They use less flash but are more for an intermediate / pro. Basically they are 'timed' salutes made from card, paper and sawdust (very important) and use blackmatch for a delay. They are very nice, quite noisy and are guaranteed to impress.

Passfire have an article (also found in Pyrotechnica 4 I think?)

[Jerronimo]

Yeah, I did the opposite and assumed cylinder shells. Having said that, I just watched the video of your 3" shell, and the break was definately better than mine (70mm), which are broken with plain BP on Rice Krispies. Nice work!

Thanks phoenix,

I described the construction in the starformulas tread.

[Greg T]

Thanks for all the advice!

If I do use a burst charge containing chorates/ perchlorates, am I right in assuming that I cannot use stars that are composed with elements of sulphur in them (due to the obvious danger of mixing the two)?

[Richard H]

It would be unwise to do so without a physical barrier between the two, e.g. a tissue paper layer between the burst charge and the stars. I personally avoid chlorates altogether.

[miniskinny]

Would flash powder be even considerable in a mix containing flash powder and Naphalene? Using just around 10 grams in the center of the shell, and then having the napth all around it? Maybe have the flash powder in a baggie, with the fuse taped inside the bag?

[Matt]

I would imagine flash wouldnt even start to light napthalene. However never having tried it i could be wrong.... but probably not. If you want to make a fireball in the sky using nap, use BP. If you need to use flash, use a flamable liquid. Constructed as a lampara shell. however that is considered a rather advanced project.

-Matt

[adamw]

I dont think I've even seen Naphthalene NOT ingnite with flash. If you are still unsure, mix a few % BP with the nap to aid ignition.

[missileman]

Alright, yes flash powder is and should be a sensitive topic, but I haven't really seen anybody hit the subject that directly on this forum, so I feel that I should start up the questions and answers.
Alright, first off, I know that flash powders are to be used only in small amounts, perhaps larger amounts in mortors, but what are good formulas for specific flashes?
I have found several, but I think I'll ask if I can share them online before I actually do?
until my next response,
-mini
by the way, I was reading a post about BP growing white stuff, and you guys referring to it as 'mould'. Do you guys really spell 'mold' that way? I was confused, and thought it was pronounced "mowld". Hmm. That's all I wanted to say...

The best flash , ie the most powerful is obtained with the following formular as long as the materials are correctly mixed and sourced in the finest mesh sizes

64% Potassium Perchlorate
25% Magnesium Powder 600mesh or finer
10% Antimony trisulphide 325mesh.
3.5% sulphur
By mixing the non oxidiser components for an extensive period then diaper mix the pot prechlorate in haveing screeded it to remove any lumps. once this is complete i put the compound in a rubber ball mill with about 8-10 corks from wine bottles to help in the mixing. Although it is recommended that ball milling is a definate no no this is just a gentle tumble together with no friction. For supply info please e-mail me, Missileman

[Richard H]

Please remember to spell check your posts BEFORE posting. Regarding flash, I don't like the idea of any form of mechanical mixing UNLESS the mill is operated remotely. The traditional diaper method is tried, tested, and above all relatively safe.

That is an extremely powerful flash powder formula, and I would strongly advise that only experienced persons make it, and only then in very small amounts!

[miniskinny]

And doesn't Pyro Antimony make flash powder ignite more easily, and at a lower temp.?? Like Richard said, it's NEVER, ever, a good idea to mix flash powder in a container, especially a machine-operated one. And if you've been foolish enough to do it in the past, and by a miracle you're still in one piece, that DOESN'T mean that there won't be ignition. If you are a beginner at making flash powder, I suggest making it with lower mesh aluminum first, not magnesium, like 400 mesh aluminum works for a less-powerful flash. Also, how would you need a more powerful flash than 400 mesh? the more power flashpowder gets, I've picked up that it gets more sensitive as well.

[RegimentalPyro]

Further update regarding the Fargo flash accident. Sobering stuff.

As everyone should now be aware, a very serious accident happened on Friday, August 13, 2004 at the PGI convention in Fargo, ND. On that afternoon, Allen Poole, Mike Barnes and Kelly Malone were at the Ground Salute Range engaged in the manufacture of a very large salute, contrary to several PGI rules and regulations, when a violent explosion occurred. Mr. Poole and Mr. Barnes live in Toledo, Ohio and Mr. Malone is from Cortland, Illinois.

Mr. Poole, Mr. Barnes and Mr. Malone manufactured a very large batch of flash powder. The flash composition contained potassium perchlorate, Indian blackhead aluminum and antimony trisulfide. After tumbling the flash powder composition in a box to mix it, the flash powder was placed into a salute casing. At some point during the process, flash powder was spilled onto the ground near them. Before placing the top disk on the salute casing, one of the men walked, shuffled or dragged his feet through the spilled flash powder causing it to ignite. The fire the from the spilled flash powder ignited much larger quantity of flash powder in the still-open salute casing which exploded with extreme violence.

Mr. Poole, Mr. Barnes and Mr. Malone all received extensive and serious injuries. Mr. Poole was less severely injured as compared to Mr. Malone and Mr. Barnes. Mr. Poole?s injuries include lacerations and burns to his lower extremities as well as ?peppering? wounds on his torso. Mr. Barnes had laceration wounds to his lower extremities and torso area. He also had burn injuries and peppering injuries. Mr. Malone received extreme laceration wounds to his lower extremities and burns.

Mr. Poole has been released from the hospital and has returned home. Mr. Malone and Mr. Barnes remain hospitalized at Innovis Hospital in Fargo. Mr. Malone and Mr. Barnes have been described to be in serious but stable condition. They are fully expected to survive their injuries. They have family with them in Fargo and have been communicating with the hospital staff and their family members since the beginning of the week.

The Board Members of the PGI are thankful that there was no loss of life in this accident. The Board has continued to offer assistance to the injured and wishes them speedy recoveries. However, the Board must also consider appropriate disciplinary steps to be taken against them for their egregious violation of the PGI safety rules and regulations. The Board is reviewing several options and will inform the Guild of its decision at the appropriate time.

Can I please ask everybody reading this to think exceedingly hard about whether they really need to use flash, and how to minimise the risks BEFORE even touching the damn stuff.......

I'll start.

When I mix it I do so in 10g batches so there is never more than 10g at one time.

I mix outside wearing a full face shield, gloves and a leatherjacket, using the diapering method. The ingredients are prescreened to ensure no lumps need poking/prodding out.

The storage container does not use a screwtop to ensure friction from unscrewing doesn't set it off and has a low electrostatic value. I store the stuff in a separate area to all my other comps. I ensure all other comps are safely out of the work area before fetching the container and I put it back the instant it is used. I've never used more than about a gram at once in any of my devices.

It's not because this stuff is powerful [It is]. It's simply because it is so easy to set this stuff off accidentally......

Even the bloody cat is locked up because he is a static risk!

[Rhodri]

Words of the Wise:

AMEN