Anodized aluminum

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Smitty

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Sep 24, 2007
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Does anyone know whether the anodized aluminum with different colors can be sold as clean aluminum or non clean?
 
The colors are dyes that are absorbed into the porous anodized (aluminum oxide) layer. The gold looking color most probably isn't gold. I've only seen real gold plate on aluminum a few times in my life.

http://www.caswellplating.com/kits/anodizedye.htm

A long time ago, in a refinery I worked at, we had about 1000# of titanium sheet that had a very gold looking color on it. I hadn't heard of anodized titanium, at the time, and was convinced that it was gold plating. I wasted several hours screwing around with it until someone told me it was dyed anodizing.
 
The anodized aluminum of different colors usually is the heavier thickness metal and falls into the MX6000 scrap aluminum category at scrap yards. The anodized aluminum I run across is often heat sinks out of computer equipment. I've never had any aluminum downgraded to a lower price because it was painted or colored. I always mix the anodized stuff in with other unanodized metal so when the scalemaster sees it he is seeing mostly uncolored aluminum. In other words don't separate out the colored metal from the regular aluminum. If the scale master does say something about it then you can simply pick it out of the box if it is a problem. Also it wouldn't hurt to pack the box of aluminum you have to sell with the colored stuff on the bottom. Scalemasters and their helpers often don't have time to check everything out in a load so they run on good faith a lot of the time as to what exactly is in the stuff they bought. As a result some questionable stuff gets through their scrutiny on occasion. Imagine that :!: :?: :!: :?: :!: :?: Regards, Chris.
 
When Hyderconsulting said ''I've never had any aluminum downgraded to a lower price because it was painted or colored.''

Why is it that people say that you get paid more per pound if the soda tabs are removed and sold seperate than the painted can? I figure because the tabs were considered clean aluminum and the cans had paint on them. Mis-conception or Urban legend? I'm pretty sure someone here can shed some light on this subjet.
 
It's an urban legend! Where this developed from is that the tabs on soda cans can be turned in to charity groups, Ronald McDonald House specifically I believe, who in turn have a donation program where for each pound of soda can tabs is collected from the the public McDonald's restaurants (and perhaps other businesses also) donate so much money to the charity. In other words the tabs are worth a lot of money by the pound to the charity but not to you or anyone else publicly. As a result an extensive urban legend has developed aroung this charity program which is basically about you inquired here about. Now oddly enough if you collect a few pounds of the tabs or even less and put them up for sale on ebay you will probably get more for them than what the scrapyard will pay you. Who buys them on ebay and why? Some of the buyers make handicrafts from them, some of the buyers get them to give to charity who benefit, and some of the buyers believe in the urban legend that there is something special about these tabs because of what they are made of and they are worth a lot of money per pound. I had a guy stop by my house one day and told me that he heard that a milk jug full of them was worth a $1,000. I had to bust his balloon so to speak. Boy was he disappointed! If anyone thinks I'm wrong about this then be sure to go ahead and straighten me out and let me know what scrapyard is going to pay all this money for a gallon of soda can tabs. I haven't found it yet and I bet I don't ever. Regards, Chris.
 
Different grade of aluminum. Cost more to refine and produce.
Most aluminum cola cans made in North America contain two different aluminum alloys. The can body is composed of aluminum
alloy 3004 or 3104, whereas the ends of the can are aluminum alloy 5182 ( tabs also ).

Aluminum 3004 contains approximately 97.8% aluminum, 1.2% manganese, and 1.0% magnesium (aluminum 3104 is very similar in composition).

Aluminum 5182 contains 95.2% aluminum, 4.5% magnesium, and 0.35% manganese. Alloys in the 5 series are good at resisting corrosion.

The tabs are actually a dirtier grade of Aluminum. The myth that you can get more for these is just that, a myth. They fetch the same price as far as scrap is concerned. Just scrap the whole can.

1xxx — High purity aluminum, at least 99% pure. Primarily used in electrical and chemical applications.
2xxx — Aluminum–copper alloys. Commonly used in aircraft bodies.
3xxx — Aluminum–manganese alloys (up to 1.5% manganese). Good workability; frequently produced as sheet aluminum.
4xxx — Aluminum–silicon alloys. In great demand for architectural applications.
5xxx — Aluminum–magnesium alloys (containing small amounts of manganese). This is a fairly strong alloy and has excellent
corrosion resistance.
6xxx — Aluminum–silicon–magnesium alloys. Medium strength; also good at resisting corrosion.
7xxx — Aluminum–zinc–magnesium alloys. Very durable; commonly used in architectural structures.
 
I'm not so sure about "urban legend". I sell thousands of pounds of Aluminum to several buyers and everyone of them pay more for "clean" umpainted or coated Aluminum. Usually 10-15 cent difference. And further seperating the different alloys pays an even higher price. When your dealing with 3000lbs, 10 cents is a big difference.
 
OK, Now let's put this in proper perspective. ThePierCer, you are technically correct about more being paid for clean aluminum versus painted or coated aluminum and even more being paid for aluminum separated out by it's alloy numbers. However, Smitty is talking about aluminum pull tabs which is very small amounts of aluminum to be fooling with. If you were to take the trouble to separate these out and take them to the scrap yard they really wouldn't pay you any more than what they pay for aluminum cans. They would probably look at you a little funny, give you a little money for a few pounds of of pull tabs (if that much in weight) and then take them over to Ronald McDonald's House to help them with their cause.
Now I'm not trying to be contrite or make fun of any one here. I'm just being logical and realistic about the pull tab thing. It is urban legend about their big scrap value.
It may be very possible to collect enough of them, post them at auction on ebay and collect a better price than scrap value. Try it and see. In the meantime if anyone has ever sold these things for big money then let us all know and we will skip all this work in gold scrap. Regards, Chris.
 
hyderconsulting,
what I was trying to say, keeping the origonal post in mind, that it does makes a difference in grade if the can is painted or not. I looked at the pul-tabs as an extraordinary example.
I misunderstood and thought you meant seperating coated from bare aluminum was urban legend.
 
goldsilverpro said:
The colors are dyes that are absorbed into the porous anodized (aluminum oxide) layer. The gold looking color most probably isn't gold. I've only seen real gold plate on aluminum a few times in my life.

http://www.caswellplating.com/kits/anodizedye.htm

A long time ago, in a refinery I worked at, we had about 1000# of titanium sheet that had a very gold looking color on it. I hadn't heard of anodized titanium, at the time, and was convinced that it was gold plating. I wasted several hours screwing around with it until someone told me it was dyed anodizing.

Au plating on Aluminum looks surprisingly less "golden" than anodizing that is gold in color.. I've seen two types of Au plating on aluminum.. either it is going to be REALLY yellow like the stuff you see on connector pins, etc.. like this..

[img:200:165]http://www.vandenhul.com/UserFiles/Image/Accessories/cartridgeclips.jpg[/img]


or in the case of reflective optics, it will be dark, almost like highly polished yellow brass, but darker.. like so..

[img:243:169]http://www.lasergold.com/images/image_4.jpg[/img]

The best source for Au plating on Aluminum is going to be mirrors for optics firms (ahem.. I work in the field).. They use Au plated mirrors for IR aplications.. IR reflects nicely off gold, but honestly, if you find mirrors like that, you may even make out better reselling it as an optical mirror.. don't be fooled by "scratches" or "digs/pits", they're still useful believe it or not.. I work in a precision optics firm and some of the mirrors we use on our test stand are surprisingly old and have seen much abuse, but they work for our purposes.. don't just discard because they're not "pristine" ;)

FYI.. (they can be made of Aluminum, Silicon Carbide, Beryllium/Copper (be careful with that stuff), Titanium.. etc)
 
There's nothing on the planet that has the appearance of real gold, especially when you compare the 2 side by side. The more that you're around real gold, in all its forms, the less you'll be fooled by non-gold objects.
 
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