Rabbit Posted December 14, 2009 Posted December 14, 2009 Takeo Shimizu states "fine" flake aluminium in his silver star composition, brilliant core and the core coating composition (page 219-200 in Fireworks, the art, science and technique).But what is fine flake? is it the same as the bright aluminium? Or does he mean dark pyro alu?
Mumbles Posted December 14, 2009 Posted December 14, 2009 I'd have to go look it up again, but I would think that it would refer to bright flake Al. There is another type (sorry I don't know the number off hand), that is -120+325 mesh, and every bit as messy as bright flake. Sometimes it is called "fine flitters." I've taken to using that instead of bright flake in streamers and silver stars. I think that it gives a longer tail, although bright will work perfectly fine. It wouldn't be flash grade Al, like the blackheads. I have seen only a few stars where these are actually indended to be used. More often they use American Dark Al, which shouldn't be confused with the flash grades. It is a coarser particle size, being -325 mesh. It is considerably denser than a similar bright flake, and is used in some cases to make the mix handle better. As far as which one is called for, probably the bright flake. I don't see much use of dark grades of Al outside of flash in the Japanese literature.
AdmiralDonSnider Posted December 14, 2009 Posted December 14, 2009 (edited) Although your post made me doubt for a second, I´m quite sure he refers to the silvery bright flakes (nominal mesh size 200, containing particles as small as 2µ). If you look in the materials section of FAST, Shimizu says: "Aluminium powder is used in Japan in two forms; the flake aluminiumwhich looks brilliant silver and consists of small flat plates, and the atomized aluminium which looks whitish grey and consists of spherical orpebble-like grains." (p.121) Concerning the use of dark pyro grade in such "core" comps (the final color change in round stars), it should also work quite well, as there is a very similar comp in Hardt table 15-25 called "koro" calling for a dark grade. I´m not sure if dark was too popular (or even available) at the time Shimizu wrote his classic. Hope this helps Edited December 14, 2009 by AdmiralDonSnider
xetap Posted December 15, 2009 Posted December 15, 2009 From the LIST (under "A" for aluminum): "US Aluminum #808, 100-325 mesh, coated. Aluminum, fine flake, Flitters. An Aluminum used for years by many professionals for making silver Flitter Stars And Comets." Others are also listed.
dagabu Posted December 15, 2009 Posted December 15, 2009 You could shoot Phil at undergroundgadgets an email and ask him. BTW- Phil has al sorts of Al flake in stock, I got 10# of his recycled 230 mesh bright Al flake and it is fantastic in breaking glass comets (video coming soon). D
Mumbles Posted December 15, 2009 Posted December 15, 2009 Too bad the information there is false. 808 is traditional bright flake -200 or -325 or -425 depending on who you believe. The stuff I was talking about is 810. This would be the definitive post on the matter:http://groups.google.com/group/rec.pyrotec...3a7a0fc1344eb0e
dagabu Posted December 15, 2009 Posted December 15, 2009 Too bad the information there is false. Which info? Sorry, missed the segue. D
Mumbles Posted December 15, 2009 Posted December 15, 2009 The old US Bronze Al number that associates with the aluminum I was talking about. The coarser bright flake is 810, while the more traditional bright flake is 808.
xetap Posted December 17, 2009 Posted December 17, 2009 (edited) Too bad the information there is false.So, instead of being rude and just stating, "this is false"- why doncha walk your tired ass over there and correct it? I CAN'T- the edit function has expired. If you will reopen my edit function, there are several changes that need to be made. I only spent my spare time over a six month period compiling, checking, etc. that doc, you can spend a couple minutes correcting it- as was asked at the outset: "This list is not all-inclusive, nor a list of formulas. Add, modify, correct or edit as you see fit. Please advise if there are any glaring inaccuracies or omissions.". They say the road to hell is paved w/good intentions. Edited December 17, 2009 by xetap
Mumbles Posted December 17, 2009 Posted December 17, 2009 That came off far more blunt that I was intending. I was just trying to point out the stuff that I have, that I mentioned previously, is the US810. It is a somewhat coarser grade of what people traditionally think of as bright flake powders.
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