Aluminum Turnings/shavings

[Swede]

For years, I have been throwing out the huge volumes of aluminum chips and turnings ("swarf") from my machine shop. It was always oily, messy, sharp, and not worth recycling because I did not produce them on a scale to make it worthwhile.

 

http://www.5bears.com/firew/nrt04a.jpg

 

I have literally gallons of this stuff. Most of it is fairly fine, and can vary from ribbons, to little nuggets, shavings, all sorts of shapes and sizes.

 

It is not pure aluminum. Usually it is 6000 series, sometimes 7000 or 2000. The numbers indicate the major alloying elements, like copper, silicon, and zinc.

 

Question - Can I turn this aluminum waste into useable pyro material? I am not interested in flash, I am more interested in visual effects from coarser aluminum. Any thoughts or tips? I'd rather not waste my time if the alloying elements are going to make the stuff worthless. As always, THANKS!

[oskarchem]

Humm.. You can use that aluminium in firefly compositions where large flake aluminium is required.

[Pretty green flame]

Humm.. You can use that aluminium in firefly compositions where large flake aluminium is required.

Yes but technically it's not flake. I say chuck it in a ball mill with some heavy steel media for a day, by doing this you should break up the larger pieces into something smaller, finally sieve out the usable material, say atleast -40mesh. And regrind the stuff that doesn't pass through a 40mesh sieve.

[Swede]

You guys wouldn't anticipate any problems from the alloying elements, then? Worst case would be 4 to 5 % Cu, Si, Fe, Mn. A bonus would be 7075 which has some Mg content, but the other alloys have different elements as alloy constituents.

[psyco_1322]

There should be no problem with the alloys. Most of the time they are not even full percentages, they usually all have decimals in front of them if you know what I mean.

[Sylar]

Except for the copper alloys, I see no possible problems.

 

Copper has this tendency to go form explosive or unstable complexes with ammonium salts. In how far this is a problem with the alloys you use is a matter of percentages.

 

A possible test would be to dissolve some of the aluminium of questionable purity in sulfuric acid and check for the telltale copper blue?

[Mumbles]

Most of the time the coarser aluminum is used in blackpowder type compositions, or composition of the same chemicals. I see no potential reaction problems with the stuff, as long as it's not too fine.

 

I'd get a set of screens and start screening out the really coarse and really fine. Some of the prettiest comets I've ever made used an aluminum that ran from about 16 mesh to 80 mesh. It was all flake. You might want to do some experimentation. You may need to use a smaller bottom cutoff to keep the aluminum from burning to the ground.