Photo Flash

[Fly]

I saw some of these years ago at some display.They are really bright,but neat.I was thinking

of making one.I can't find much info, so again I turn to you.If I remember they don't make

much noise but are really bright.

 

Would this be a diaper method of mixing & how shock sensitive would it be for a aerial shell?

 

40.00% Potassium Perchlorate

34.00% Magnesium

26.00% Aluminium

 

FlyB)

[Ralph]

really another flash thread ?

 

 

if made with magnesium that isnt to fine (something around 50-150mesh) than it inst to sensitive and diapering would be the best method I made a barium sulfate based supper bright flash but that was lost when one of my hardrives in the raid aray got the click of death so Ill get the formula of someone I sent it to tomorow and post it

[Mumbles]

There are easier and safer ways to make photoflash. One way is to mix wood meal into normal flash. A 75:25 mix of flash and fine sawdust is said to do the trick by Dave Stoddard. "...its guaranteed to weld your retinas to the back of your eyeballs on a dark night"

 

An easier, and safer method is a 50:50 mix of granular BP and any fine metal. Mg, Dark flake Al, bright flake Al, fine Titanium, etc. Danny Creagan recommends using felt on one end to help compress everything without providing confinement. That really is the key to these things. You need as little confinement as you can get away with. You can get certain sized felt pads at the hardware store for the bottom of furniture if you need a convenient source. Felt sheets aren't thick enough, but you could probably stack a bunch, say 1/3 to 1/2 the ID in thickness

 

They really aren't designed for single-fire aerial shells. They're best as inserts or rocket headers. Shells have to be far too strong to give a real photoflash.

[jwitt]

Hmm...actually it would be interesting to know how to make a maximum light output flash with minimum noise / chance of deflagration. Maybe I just missed it since I'm not actively pursuing it. Could be fun to rig up a bunch of flash pots though? I'd personally be too worried about the devices going "bang" to experiment with 70/30 in that application.

 

Oh, I see Mumbles helped out in that regard as I was typing.

 

Seems that there's a large risk of creating a salute if rigging this, say, in a tube. But in a bag? I'd like to make a few flash pots for Sat. night's shoot, but it's probably too risky to employ 'em without prior testing.

Edited July 28, 2010 by jwitt

[Fly]

 

Mumbles I like the BP mix better, SAVE!But counld a guy not use cotton instead of

felt?

Fly:whistle:

[Twotails]

Personaly, if i need a high output flare(or flash composition) I have found DMSO works. 70/30 perchlorate to DMSO with 5% metal added. It can be tinted a light blue with 3% black copper oxide and 2% Saran(I've tried it with 5% Al, 3% black copper oxide, and 2% saran, thin with DMSO to bring back to a semi-liquid) im still testing it, but it realy shows it may work. its ready to be primed(i've used a tiny bit of 70/30 and visco) its used wet, no need to dry. It is a little smokey(probably becouse the fule/Ox mixture is outta wack) but bright, perfect for pots, as it can me mixed in a bag, poured, primed and fused on site.

 

I've used Mg/Mg sulfate for light production i think the Mg metal was 100-200 mesh, and the sulfate was powderd fine. i tend to stay away from Mg flash for the most part.

 

 

[dagabu]

You need to be very careful with DMSO since its sold as the carrier of other drugs that are applied to the skin and immediately absorbed. Nicotine patches and the like use DMSO (and other chemicals) to carry the chems past the skin and into your body.

[dagabu]

I would be quite concerned with mixing potassium perchlorate with such a high ratio of magnesium.

 

Why? a 60:40 ratio will burn hot but will not deflagrate as would a 30:70 ratio.

 

*sigh*

[Siegmund]

A few photographic-history sites I peeked at gave the impression that accidental fire, not explosions, was the big hazard from 1900-era photo flash powder, with photo studios quite prone to burning down. Having your comp "only" spontaneously burn hot is still not desirable.

 

One thing you might ask yourself is whether you need the very quick bright flash of a photo flash to freeze moving objects on firm, or just a bright light that last slightly longer. Most any form of burning Mg is awfully bright; the reason to abandon the 1875-era photo illumination method, blowing magnesium dust into a flame, was to freeze motion more than to get a brighter light.

 

That aside, I still look forward to hearing what comps get suggested in this thread. The last thing I'd recommend is using a authentic magnesium-and-chlorate recipe.

Edited July 29, 2010 by Siegmund

[Twotails]

Ah, yes DMSO as a carrier, I work with it in a bag with gloves, wouldent be a good idea to use a barium salt and get it on exposed skin(I would never try that mind you, last thing I need is barium poisoning)

[dagabu]

Ah, yes DMSO as a carrier, I work with it in a bag with gloves, wouldent be a good idea to use a barium salt and get it on exposed skin(I would never try that mind you, last thing I need is barium poisoning)

 

Sorry Two, I didn't mean to sound all "know it all". I couldn't think of the chem I REALLY didn't want in me, Dichromate.

[Fly]

Mumbles I tried that 75:25 mix of flash and fine sawdust tonight & WOW!That must be what I saw years

ago.I mean to tell you that's one bright mother.

 

It is funny to, very little bang.I tested on the ground.Tomorrow she will be headed toword the sky.

 

Fly

[Fly]

I had that backword, 75 sawdust & 25 flash.

[Peret]

If it's light you want rather than sound, you should have some barium in there - incandescent barium oxide emits a broad white light spectrum that about doubles whatever other light emitters you have. It only gives green if there's chlorine present. Here's a military photoflash formula from Conkling -

 

Barium nitrate 38.3

Potassium nitrate 25.2

Magnesium 29.9

wax 6.7

oil 2.9

 

It looks hard to light.

[Fly]

Thanks Peret!But I can tell you this,it's like looking at one of those ole flash bulbs.I tested this thing

on the ground last night & it took 5 min to get the spot to go away from my eyes.

 

What really kind of neat is the lack of noise.It makes a small pop but it,s so differant.

 

A larger one in the sky is really neat to see.I guess I need to make larger rocket tooling so I can launch

some bigger ones.

 

Fly

[qwezxc12]

A while ago, I made a shell of shells loaded with bombettes charged with 50:50 KPerc/-600mesh MgAl. I'll never do that again - they were bright to the point of ruining my night vision. We had to delay launching more stuff until all the puple spots went away.

[jwitt]

That's just the sort of comp I was hoping to find from this thread.

 

No time to mess with it this weekend (even though I do have a pile of sawdust from building another rack) but it sounds like it would be fun to rig up a whole bunch of little flashes, maybe set 'em off after deploying a big smoke cloud.

 

Hmm....I guess it would be more practical to learn how to make strobes, but "ooh this is a fun and different way of doing things!"

[Fly]

Well I think something that helped,was I ran the sawdust threw the coffee mill to make real fine.I'm going

to play around with this some more & let you guy in on my findings.

 

Fly

[dagabu]

I had that backword, 75 sawdust & 25 flash.

 

I made that mistake the first time I was told about the mix, it still boomed jut fine

[Mumbles]

I probably should include the full textual instructions I have on this. I'll try to do it when I get home tonight. It was originally done with wood meal, though anything -60 mesh is said to be just fine. Wood meal is extremely fine stuff. It makes sense that the finer stuff was working better for you.

 

I have a few things dreamed up for some day.

 

One is what I am tentatively calling an Echo hammer. It's just a hammer shell with alternating photoflash and dark flash inserts. Bright flash....report with no light, repeat.

 

This also kind of goes along with the above thing, but I want to put in a faux bottom shot before the real one. Everyone always braces before the big bottom shots when they're expecting them, so I want to catch them off guard, let them laugh about it a little bit and then BOOM.

[Mumbles]

Here are the notes I have saved:

 

http://www.passfire.com/forum/forums/thread-view.asp?tid=11698&posts=30&highlight=photoflash%20felt&highlightmode=1#M107157

 

 

Retrieved via Ned Gorski on passfire, 4/14/2010

This is Dave Stoddard's note on the role of wood meal quieting flash reports:

 

 

" I discovered through

 

serendipity about ten years ago that mixing flash powder with sawdust

 

allows you to create a noiseless salute - all flash an no bang. It is a

useful

 

technique if you want to make salutes to time with music, but you don't

 

want to hear the delayed bang that follows.

 

 

 

It only takes 25 percent sawdust (by weight) -- I used wood meal from

 

Skylighter -- combined with 75 percent flash to completely eliminate the

 

bang. I believe I published this in AFN many years ago. Brings a whole

 

new meaning to the term "flashlight cracker". Plus, it extends the burn

 

time on the flash - its guaranteed to weld your retinas to the back of

 

your eyeballs on a dark night ."

 

 

Here are some more notes from Dave:

 

"Mix standard flash (70/30) 75% by weight with 25% by weight wood meal.

 

Makes a whole lot of light and no boom. Depending on the amount of

 

flash powder you use, you may need to adjust this slightly. However, I

 

have had good results with a 75/25 mix. I should probably login more

 

often to Passfire. Best,"

 

 

And in response to a question about whether 60-mesh wood dust is fine enough:

 

 

"Dunno – 60 mesh is pretty fine. You will find that the volume of wood meal

 

is equal to (or greater than) then volume of flash powder, even when it

 

is mixed 75% flash and 25% meal by weight. If you have some 1 inch ID

 

salute tubes, make up some bangers and try it. You will know whether

 

it works pretty easily. "

 

 

From Danny Creagan, same thread

 

 

Joel and I recently tested some photo-flash mixes. I shot a couple of 4 Photo Flash and Report headers at the IPA meet.

 

See: http://www.wichitabuggywhip.com/fireworks/rockets/fivetimes/fivetim...

 

If you just want light and little sound then:

 

 

 

Make an insert tube (or whatever)

Plug one end with your normal time fuse setup.

Add 1/2 2FA and 1/2 325 or finer Mg.

Plug the other end with 3/4" thick felt - you can get it in the form of large furniture scooters at a hardware store. I punched it out with a sharpened end of iron pipe.

 

You can also use:

 

Fine Ti (Armstrong Ti works great but fine atomized also works)

Fine Dark Aluminum

Just about any fine metal - even that stupid tin man aluminum works

 

The above three items give a slightly different effect - still fairly silent but with varying degrees of spark and fallout. The Mg version is just a flash. The dark aluminum version is also fairly good and is a good substitute. The Ti versions are pretty neat because they leave a spark horse tail. The tin man aluminum gives a Ti effect but not as bright.

 

Things to watch out for:

 

Don't use too fine a BP mix (boom). Don't cap the end too tightly (boom).

 

Aaron Enzer gave me the hint at FFFF. He didn't follow through very well when I asked a few questions about it - Aaren sucks at email ;-} - but he did it at a PGI show once. He filled a bunch of ball shells with the inserts - it worked wonderfully. Joel and I tried about thirty ways of doing it and settled on the obvious one. Try it, you'll like it.