Blue Aluminum no happy!

[SharkWhisperer]

Has anybody explored any other uses for "blue aluminum" besides making large salutes? And does anybody have any updated specs on the stuff that's circulating in terms of particle size and shape constitution. It emerged as a supposedly "safer" Al for making flash in large salutes. Maybe a mix of atomized and flake of various sizes. Flash in "large" salutes made with Blue Al supposedly blows up spectacularly according to the hype and some YouTube videos, while that same perc 70/30 flash made with it won't even ignite when unconfined.

 

I call bullshit on this stuff, blue aluminum, and am asking to be educated by others who may be further up the learning curve than I am with this material.

 

I picked up a pound on a whim from an outstanding pyro supplier. It was Al powder, supposedly unique, and...on sale for $10/lb. Ok, deal. Like an Amazon "add-on" purchase.

 

It doesn't behave like atomized 5 or 30 micron and it doesn't behave like flake of any size. Or a combination. It behaves like metallic dirt. Lazy metallic dirt.

 

No, haven't used it for large salutes, but I have tried it for prime, flash, flash additive, small (1-5 gram) salutes, and even gerbs, in combination with various oxidizers and sensitizers. Poured it on a huge bonfire. Can't get it to burn! Biggest waste of money since I sent my last monthly payment to my Nigerian Finance Minister, now my accountant, that emailed that I was a wealthy man, sheesh. It IS good at slowing down your BP rate if you don't have any baking soda or chalk laying about, though. Bonus!

 

At this point, I'd make sparklers with the stuff if I could figure a way to make it burn!

 

Please share your experiences and wisdom regarding "Blue" aluminum !!!

Edited January 24, 2020 by SharkWhisperer

[SharkWhisperer]

I have a 1000x quality light microscope (can't get any higher with light; then moving into electron-microscopy because of light wavelength issues). I'm going to look at a sample of "Blue Aluminum" that I own, and will report findings.

 

Unless I accidentally mixed the useless crap into the back patio concrete during renovations...

Edited January 24, 2020 by SharkWhisperer

[a_bab]

"blue aluminium" is meant for large, safe salutes period. Even these would be hard to set off without lots of black match.

So if you bought it hoping it would work for anything else it's your fault.

It *may* work for glitters though, being atomized.

I am really curious what it looks like under microscope.

[davidh]

I've heard it's actually MORE sensitive to friction than dark AL. Frankly, I've not seen any particularly encouraging test results using blue AL.

[SharkWhisperer]

 

So if you bought it hoping it would work for anything else it's your fault.

 

It *may* work for glitters though, being atomized.

 

 

Uh, ok Church Lady, thanks for bringing that keen insight to the table!

 

Helpful? Not in the slightest. Shared wisdom or experience? I must have missed something.

 

The "atomized" tidbit was interesting, though. Can you state the particle size/range? Source? Are you sure it is all atomized; some say it is a mixture of forms?

 

My query was whether anybody had tried/accomplished any pyro task with Blue Al, besides large salutes, not if there were any random arses online that felt the desire to do some finger wagging/scolding to a stranger for questionable chem purchases.

 

Do you have anything useful to bring to this conversation, Nancy?

Edited January 25, 2020 by SharkWhisperer

[SharkWhisperer]

I've heard it's actually MORE sensitive to friction than dark AL. Frankly, I've not seen any particularly encouraging test results using blue AL.

David thanks. Can I ask where you heard about the possibility that blue Al is more friction sensitive than darks? I presume you are referring to a standard 70/30 flash mixture, yes?

 

Reason being is that I took a few grams of 70/30 made with perch and Blue Al and massaged it roughly into 150 grit sandpaper using 400 grit attached to a stick, and nada. That said, my 70/30 with perchlorate and Indian Al won't light up easily like that, either, but KClO₃ mixtures sure will. So, in my hands I'm unable to replicate, in admittedly limited testing, enhanced friction sensitivity with Blue Al vs Indian dark Al.

 

Also, I can bash blue 70/30 with a hammer all day long, whether it's a half gram unconfined or in a 0.5"-diameter (14.7 mm for our Euro friends) paper rocket tube by hammering an oak piston against it atop a concrete base and it just kinda looks back and laughs at you. Causes shrinkage, I'm told. With hot Indian Al, I get deflagration of a half gram of unconfined 70/30 maybe half the time with perch and all the time with KClO₃ as the oxy (didn't feel a pressing need to test those last two mixes with a hammer in confinement)...

Edited January 25, 2020 by SharkWhisperer

[a_bab]

Sparky Sharky, I would not buy magnalium for organic fueled stars if you know what I mean.
Don't forget that many chems we use are leftovers from other industrial processes.

The story goes like this: someone has bought/got aluminium powder in a metal drum and the top could have been painted in blue (this is why there is "black head german" or "yellow head" etc). Or the whole drum was blue: I don't know.
That someone must have tried to find a pyro use for it and he discovered it works in (large) salutes, in a safer manner.

It is a known fact the #325 atomized Al would also work in salutes with proper confinement AND a largish amount (>100g).

After all, flash needs confinement to do it's magic.

Even the waterfall, otherwise a very mild composition can explode with extreme violence in certain conditions (yes, there is a movie to prove this).

 

In conclusion, as with most of our chems that blue Al drum must be used for some specific unknown industrial process and someone found a pyro use for it: large safe salutes. But I bet it also works in glitters.

You may find another use or simply accept you lost $10.

FIY: Nitroparis, a known European supplier also sells this blue Al. The sell to large factories including Maltese ones. The smallest amount they'd sell would be a drum. But they actually buy in bulk and repack. I wouldn't be surprised if the more expensive "blue Al" is exactly the same as some other atomized variety they sell for cheaper.

http://www.nitroparis.com/productos-polvos-de-aluminio/

 

 

Now, if you really want to contribute besides crying for $10, dust off that microscope and let's see what this elusive blue Al looks under magnification: is it a mix of granular / flake? Or is it simply granular? Or wth is it?

Edited January 25, 2020 by a_bab

[SharkWhisperer]

Hey, hey, some actual useful information! You have indeed redeemed yourself. Thanks for that! You really think I give a fat rats ass about a measly $10 compared to the other ongoing thousands in assorted pyro outlays, tsk tsk? Trivia.

 

Yeah, some microscoping is in order, though I'm surprised there is not detailed info available from distributors. Unfortunately, I don't have a camera adapter for either scope eyepiece. Maybe could wing something at least mediocre with a freehand camera...

[davidh]

Oops. I had it backwards. Impact sensitive, not friction sensitive. From the test document (not mine to share):

 

Friction Testing

Each sample was rubbed for 10 seconds between a steel hammer and a ½” steel plate. None showed any signs of combustion or deflagration.

 

Impact Testing

Using the same 16 oz. hammer and steel plate 3 of the 2 BA samples and 5 of the 10890 samples were struck using a firm blow. All 6 of the BA samples deflagrated while only 2 of the 10890 samples deflagrated. Of those 2 one went off on the second blow and the other on the third.

 

All of the samples contained sulfur.

Edited January 25, 2020 by davidh

[robbo]

One more time.

 

Blue Aluminum was specifically developed to mitigate some risks in making 70/30 flash. Considerable thought went into the development. This reasoning is published and available to those who seek it.

 

It is not a blue-colored drum leftover from some other industrial process. It is a specific blend of various aluminums. Maybe other fuels? I don't know.

 

It is sold with the caveat that it requires extra ignition/pressure buildup techniques which may not be achievable in small shots.

 

No one involved with its invention or production has suggested or claimed that it can be used for anything else. I don't know it anyone has tried it as a substitute for other atomized Al products in other uses, since it is relatively expensive and formulae using cheaper aluminums have been developed and widely available before it came on the market.

 

I have bought and used the stuff and personally find no advantage, at least for me, over other cheaper salute/dark aluminums. But I've been around, worked in the industry since the 80s, and have some experience.

 

I think it is a valuable product for those intrepid amateurs who want to make large shots but are apprehensive about and/or ignorant of making and handling orthodox flash. And I'll admit that I am amazed at how inert a 70/30 mix of this stuff is.

 

and... with humility comes wisdom.

[dlking59]

Here is a quote from a supplier of "blue aluminum".

"Blue Aluminum is a fine mixture of flake and atomized aluminum that can be used for a variety of effects".

 

Another quote

"For binary mixtures of blue aluminum and potassium perchlorate include electric matches, spolettes nosed with extra black match, and burst bags/burst containers using meal D powder of rice hulls/cork particles covered with black powder. Blends of 80% blue aluminum and fine flake aluminum make ignition easier while retaining most of the ignition source risk reduction seen with 100% blue aluminum uses. The data on formulations using sulfur are also provided. The formulation of 7 parts potassium perchlorate, 1 part sulfur, and 3 parts of a blend using 80% blue aluminum and 20% German or Indian Dark flake aluminum may be ignited by simple cross-matching of time fuse and still has reduced thermal, friction, and ESD sensitivity compared to formulations using only fine flake aluminum.”

[memo]

i bought 10 pounds about 4 years ago, built 100 gram bottom shots with chlorate. they worked well.nice sound, i spiked and pasted the shells. used a bit of extra black match to make sure they lit. never a problem. they were as good as german black. also used in d1 glitter and it worked well. dont know why i quit using it. it was fine.

[Arthur]

AFAIK Blue aluminium was developed for making large salutes using ingredients that were slightly safer than using so called black flake. To work it needs to be confined well.

[Ubehage]

I used to make small salutes (firecrackers) with Blue Al and Perc 70/30.
Used to press the flash tightly into small tubes, in increments of first some flash, then a bit of BP to set it off, and flash again. BP in the middle of the tube.

There was a minimum-size tubes that was useful. Below that size, they would not go bang. They would just burn slowly.

So yea, Blue Flash can be set to burn. But it requires some heat.

 

For Blue Al to go bang, it requires some amount of hot BP (or Blackmatch) to set it off, and also requires a relatively strong confinement.

It won't go bang, unless it already is going bang. Does that make any sense?

Edited February 23, 2020 by Ubehage

[Polemos21]

I use blue in 3in cylinder shells with a burst bag works fine. I also have used them In 5in cylinder shells with just blackmatch and they are just as loud as german dark. My formula is 70/30 and 10% rice hulls to total weight with 5-10% Ti sponge. Long lasting smoke cloud. I love using thia product and i get it cheap.

[Kevisima]

It's for large, 3" and up salutes.

What everyone seems to be missing is it must 1st be mixed with German or Indian black AL, 80%blue/20%black.

Period. The end.

Don't blame the product if procedure hasn't been followed.

Another related point is your oxidizer. Does it come from the supplier in high quality?

Of course it does! BUT, you can increase the performance of your composition by screening, THEN MILLING OR GRINDING the oxidizer, usually KClO4, until it's much like a fine talcum powder. I use an el cheapo coffee grinder for about 30seconds.

The difference will be amazing. Why more pyros don't offer this hint is a mystery to me.Try it. You won't be disappointed.

NEVER grind/mill metals or compositions.

Have a good one!

[LiamPyro]

Why not just use 325 mesh bright flake, the shiny paint grade coated in stearin? Seems like this would be simpler than mixing up Blue Al with Dark Al, while still being somewhat safer due to the slippery nature of the particles and larger particle size (when compared to Dark Al).

[Conure]

I bought some blue Al from pyrogarage.com and asked them about it's particle size and got this answer:

 

Size: Mass%: Shape:

>250 um 0.6% 100% granular

150-250 um 1.7% 100% granular

74-150 um 5.1% 100% granular

37-74 um 7.5% 100% granular

20-37 um 25% 41% spherical 59% granular/flakes

10-19 um 29% 47% spherical 53% granular/flakes

4-10 um 26% 55% spherical 45% granular/flakes

1-3 um 6% 95% spherical 5% granular/flakes

 

Edit:

Damn this didnt come out as nice and ordered as I thought.

 

I did a little testing and found out that unlike 45 um Al, blue Al mixed with nitrates can be ignited with a sparkler but only burns about half of the mixture. It's melting ability in thermite is similar to that of 45 um Al.

Edited July 4, 2021 by Conure

[mx5kevin]

For flash powder blue aluminum or 30 micron aluminum must mixed with dark Al. 80 blue and 20 dark are the minimal ratio what are start to working. Need to help to ignite it the Blue Al. I using a 50:50 mixture for flash powder. For large salutes the flash effect are meters larger. Dark aluminum particles it burns too fast. What I bought in Europe is 30 micron aluminum. Mixed with KClO4 without dark al are burn like thermite. Flame cannot be colored with it like with dark Al. In large salutes compared to pure dark Al the effect are so huge that the Dark Al effect very weak compared to it. Without 30 micron mixed with maximum -400 mesh (not bright flake) only gray not firefly powder similar and alternative. Or self made homemade Al with ball mill. When mixed with dark Al the flash effect are much more brighter. The flash is slightly slower, but it does not degrade its performance significantly. In large salutes no negative effect is felt on performance. If someone buyght 30-40 micron Al, Blue Al without dark Al not working for flash powder. It could be different the Blue Al in the US, but in Europe this is 30 micron aluminum. There is no difference between i buyght 30 micron Al or Blue Al all the same. In small firecrackers under 10g have no sense and pure dark al are much better. Safer in flash powder, I don't think that's true. Without 50:50 30 micron blue+3-7 micron dark i not make large ground salutes (with big flash effects).

[Soloserly]

This is an older thread but I've experimented a little with blue Al lately and succeeded in making silver and gold star comps that burn with intense sparks, but only when I have the ratio of oxidizer to sulfur dialed in perfectly.  Otherwise it just melts into a glob.  When I get it right, it will ignite with just a match.  

 

The video is of some of the comp dumped onto a piece of tissue paper and ignited just from the heat of the paper burning.  It is gold colored because one of the oxidizers is Sodium Nitrate.  Without the NaNO3 it burns silver.

Then comes the frustrating part; I made it into some cut stars using 1% boric acid to protect the aluminum.  The dry powder burned brilliantly when I tested it beforehand, and the test stars burned perfectly (blindingly) when I took them out of the dehydrator after 2 hours at 140 degrees, but the next day they would only burn off the prime while melting the stars into a molten ball of porous aluminum.  I'm just playing around with this stuff and not expecting to have it replace my better aluminum sources, but it sure has me perplexed as to why it would work one day and not the next.  I even tried removing water from the equation and bound some stars with NC lacquer but that was no better.  I might keep trying just for fun and will post a good comp if I can get it dialed in.  

Edited December 3 by Soloserly

[cmjlab]

Is it humid where you live?  If you put the stars that won't burn back in the dehydrator to dry another day, will they ignite then? 

FWIW - I've had strontium nitrate and sodium nitrate stars made with NC still turn to mush when left out.  The only hygroscopic stars I've had not reabsorb moisture are parlon / acetone stars (Rubber Stars).

Edited December 6 by cmjlab

[pyrojig]

Something else to note on blue Al, it is a matter of density that makes it a bigger bang. You have more weight of flash in a given cartridge than low density flake. Weight for weight there would be negligible difference. 

[Soloserly]

On 12/5/2024 at 6:49 PM, cmjlab said:

Is it humid where you live?  If you put the stars that won't burn back in the dehydrator to dry another day, will they ignite then? 

FWIW - I've had strontium nitrate and sodium nitrate stars made with NC still turn to mush when left out.  The only hygroscopic stars I've had not reabsorb moisture are parlon / acetone stars (Rubber Stars).

I tried a hotter prime and they burned pretty well, just not as reliably as I would like. I then tried adding some dark aluminum and phenolic resin and that seemed to dial it in.  I love the streamer effect.  I've tried it with both blue aluminum and -325 atomized Al and both ignited reliably.  Here's the comp as it stands: 

KNO3: 50

Sulfur: 9

Phenolic Resin: 9 (or 11 red gum if you don't have PR)

Blue Al: 23 (can also use -325 atomized Al)

Dark Pyro Al: 9

That's for silver   For Gold I replaced 14 parts of the KNO3 with NaNO3.

Using Phenolic Resin my solvent was acetone, but I'd use 100% alcohol if using red gum.  Red gum isn't as strong a binder as PR, so the stars might not be as durable.  

My next experiments will be trying again to bind with dextrin using water with boric acid.  

I don't usually worry about humidity because I live in the desert southwest.  It is sunny, warm, and very dry most of the year.  In the summer, my blackmatch dries outdoors in a couple of hours.  🙂