Richtee Posted April 22, 2008 Posted April 22, 2008 I have happened upon a small supply of bright AL. Was wondering what it's applications are. other than making a helluva mess. Man..a gram of this tossed in a car interior...YUCK! Kinda cool Tin Man effect tho. Any pointers and info appreciated... it is Alcoa 369 BA.
Frozentech Posted April 22, 2008 Posted April 22, 2008 I have happened upon a small supply of bright AL. Was wondering what it's applications are. other than making a helluva mess. Man..a gram of this tossed in a car interior...YUCK! Kinda cool Tin Man effect tho. Any pointers and info appreciated... it is Alcoa 369 BA. There are dozens of comps that use bright flake aluminum, Some glitters, comets, fuel in metallic color stars, etc... Sounds like a straight sub for "-325 mesh bright flake". Tips ? Mix the comps inside ziplock baggies. Simple Green cleaner works great for getting it off surfaces (and skin).
KinneticEnergy Posted April 22, 2008 Posted April 22, 2008 Is it bright AL flake? Where did you happen upon this stuff? The flake stuff I think you're talking about can be used to make some nice bright flares.
Richtee Posted April 22, 2008 Author Posted April 22, 2008 There are dozens of comps that use bright flake aluminum, Some glitters, comets, fuel in metallic color stars, etc... Sounds like a straight sub for "-325 mesh bright flake". Tips ? Mix the comps inside ziplock baggies. Simple Green cleaner works great for getting it off surfaces (and skin). Ahh I do have the Simple Green stuff..use it for projector screens...great stuff! I did find a few comps for stars with it as well. Lacking other ingredients, but have rectified that thru Skylighter and others this AM. I have some "dragon's eggs" cores on the way as well, and am gonna try the media-less mill jar thingie. I guess I should look into a roller project, but the jar works OK. It is indeed -325 mesh bright flake. I have not tried comets yet either. The crossette has my imagination swiring tho :{) Thank you for the reply!
Photon_Junkie Posted April 29, 2008 Posted April 29, 2008 Hi, long time reader, first time poster. I may have come to this discussion late and this may have already been mentioned. But that bright aluminum flake should be treated with about 1% boric acid. This keeps the aluminum from reacting with water. Not normally that bad, it can become pretty exothermic and cause bad things to happen. Hope that helps!
al93535 Posted April 30, 2008 Posted April 30, 2008 Actually that would only be helpful when the aluminum is in contact with potassium nitrate while its wet. When completely dry, there is no reaction, when the aluminum is coated there is no reaction, when the aluminum is larger mesh sizes the reaction proceeds so slowly, it can be disregarded. Add boric acid to comps that will be wetted with water, have potassium nitrate and any aluminum that is finer then 100 mesh and is uncoated. Your bright aluminum should be strearin coated, and it should be just fine.
qwezxc12 Posted April 30, 2008 Posted April 30, 2008 I'll also stick my head on the block and say the the Nitrate / Al reaction is an alkaline one, hence the addition of Boric Acid to lower the Ph of the damp composition to prevent the reaction. Why do I mention the obvious? Because I've seen many people recommend adding Boric Acid to nitrate-oxidized glitter comps to "protect" the Al, "beacuse it can't hurt"...glitter comps that are by nature alkaline due to the carbonates used as a burn rate modifier. Adding 1% Boric Acid to a mix that already has 7% carbonate isn't going to do anything, but neutralize the Boric Acid.
Mumbles Posted April 30, 2008 Posted April 30, 2008 I've said this elsewhere, but have only really done one very basic test to try to confirm it one way or another. Boric acid isn't a traditional acid, in that it produces H+. It is in the sense that it accepts OH-. It may seem like a nit picky detail, but it makes a world of difference here. It make absorb an OH- from the bases, but it wont destroy the carbonate in the sense that acetic acid or HCl would with expulsion of CO2. Try mixing boric acid and sodium bicarbonate. When I did it, there was no fizzing. I don't know what kind of impact this would have on the comp, but I'd still think that the boric acid would be "used up" in a sense. Upon drying though, even if it stays as borate (B(OH)4-), you'd still have bicarbonate present to retard the reaction. I'd like to hear if anyone had reactions with heavily base retarded glitters with the addition of boric acid, or if the addition of boric acid to heavily base retarded glitters hurt the reaction in some way. Also, might be worth noting, but Barium and Strontium carbonates are so insoluble, that combined with the KNO3 going into solution, the amount of basicity they will add to the composition is probably negligible. So, unless you are using sodium (bi)carbonate, that 1% boric acid can neutralize all the OH- produced by the carbonates, and then significantly more.
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