You all have valid points. Irishman said it best. I am generally not much of a charitable person, as I am on a limited budget. Meaning all of my living expenses are paid directly by the county to my creditors while I am waiting for my transplant to take place. I would rather just give the tabs than not, no matter how small the contribution. It would be just as simple to drop of a cash donation at McDonalds, but even at their prices, I don’t make a regular habit of eating out. And to Mr. CurtC-To use a well worn cliche-If this kidney failure thing can happen to me, it can happen to anyone! Maybe in your case it will be cancer, or some type of disabling disease,(hopefull not) then you’ll see. By the way, I am not Freddy Fender. I am a 30 year old single mother of two who quit her job as a Funeral Director to stay at home with my youngest child and to patiently wait for my kidney transplant as my condition continues to slowly worsen.
The point is not whether it’s worthwhile to recycle pop tabs–the point is whether it’s an actual fundraising thing. The answer is yes, McDonalds will accept pop tabs, but they didn’t initiate the program, they just got on the bandwagon because people banged them over the head with the Urban Legend for so long that they gave up trying to explain, “No, we’re not collecting pop tabs.”
And I think this is a perfectly logical explanation for “why only the tabs”:
They’re not seriously trying to raise money for kidney research with itty-bitty dribs and drabs of aluminum. They just humoring the Great American Urban Legend-Believing Public. With a weary sigh, McDs sez, “All right, we’ll accept the pulltabs–but just the tabs, since we don’t wanna be responsible for taking aluminum out of the mouths of the Boy Scouts and the Jaycees and all the other ‘bring in all your pop cans’ programs out there in the Heartland.”
It’s not meant to be a realistic fundraiser, in other words.
Thanks you for opinion. It pretty much sums up the idea. I know people are not beating down the path to find places to deposit their tabs…I’m sure you’re right about it being an urban legend, one that has been around as long as I can remember.
Quite possibly not. Beverage cans are made from different alloys for the top and walls, so when they’re recycled they have to separate them in a complex way. The results aren’t as good as when the re-melt stock is more well behaved - this way they get a higher grade alloy out of it.
I’d give a cite, but I’m tired and google isn’t really cooperating with me right now.
But the bottom line is that the pull tab and coined pop-out “drink hole” are higher strength than the body, which is soft so it can be drawn into a can shape at manufacture. I can see the payoff of having people separate them for the founders’ convenience.
Thanks for the information.
Considering that this issue comes up often, I would appreciate it if you would give a cite.
Can anyone play?
I found the following on a website for the U.S. Army Environmental Center: http://aec.army.mil/usaec/p2/app04a.html
Well, I know can tops and bodies are made of different alloys. What I think Arnold was asking for (and if he wasn’t, I am) is a cite verifying that “when [pop cans are] recycled they have to separate them in a complex way,” as Thrasymachus claimed. Intuitively, it seems a whole heck of a lot easier to mix the correct scrap (per chukhung’s cite), or add alloying elements as needed to attain the correct alloy, rather than to seperate the can bodies and tops. So I still disbelieve the seperation claim.
That cite implies that it’s the entire can top, not just the tab, that’s made of a different alloy. If that’s the case, pulling the tabs off doesn’t accomplish a thing.
It comes up often, eh? Alright, I read it somewhere…poring over personal library… ahha. So far I have two:
Askeland, Donald R. The Science and Engineering of Materials - 3rd Ed, ISBN 0-534-93423-4, 1994 PWS Publishing, pp 389.
“The beverage cans are made from two aluminum alloys, 3004 for the main body and 5182 for the lids. The 3004 has the exceptional formability needed to perform the deep drawing process, the 5182 alloy is harder and permits the pull-tops to function properly.”
“When the [entire] cans are re-melted, the resulting alloy contains both Mg and Mn and is not suitable for either application.”
It then talks about two separation methods which I presume are still in use:
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Chlorine gas bubbling (which reacts with magnesium and removes it);
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Shredding (the harder 5182 alloy breaks into smaller pieces in a certain temperature range, which can be screened out from the larger).
From Callister, William D, Materials Science and Engineering : an introduction - 5th ed, ISBN 0-471-32013-7, 199 John Wiley & Sons, pp 778.
[picture of cans on a belt, courtesy of Alcoa]
“These cans will be crushed and pressed into bales (shown in the background) and then shredded into small pieces. Ferrous and non-ferrous metal contaminants are next eliminated, and the decorative coating is removed in a de-laquering operation. ** A thermomechanical process then separates can bodies (alloy 3004) from the lids (alloy 5182).**”
(bolding mine)
Now just because something is in a book doesn’t mean that it’s true necessarily, or that it still is; but I’d probably have to rustle up an actual aluminum smelter or bottler to get any better StraightDope on it. Secondary sources being what they are and all… I imagine that different founders have different ways of doing things, just like everything else in industry, and so this may or may not be representative practice.
Having melted and cast aluminum in a backyard forge myself however, I can see why it might be worth something to have clean consistent scrap like pop tabs to start from.
But that still doesn’t take into account the make-up of the pull tabs, which is what this thread is all about in the first place. Even if you could prove that the pull-tabs were made of an unusable material, that would only prove that they would be the part of the can you wouldn’t want to contribute for money in the first place.
Well, Czarcasm, the pull-tabs aren’t unusable at all, they’re just a different alloy. Agreed that Thrasymachus’s cite is somewhat unclear as to what the pull-tabs are made of, specifically (although the implication is that it’s 5182), but it’s likely that 1) all pull-tabs are made of the same alloy, whatever that may be, and 2) that alloy is not the same as the alloy used to make the can bodies.
Seperating out the pull tabs won’t decrease the work involved in the eventual process of seperating can from top, but it will result in a big pile of tabs which are the same alloy. So a pile of tabs ought to be more valuable, per pound, than a pile of cans, because no alloy seperation or adjustment needs to be done. Does this make any difference to the aluminum recycling places, given that they probably have already invested in an automated setup to take care of whole-can recycling, in one way or another? I dunno.
It is interesting to note that even with the complex and expensive processes in recycling cans, it is still cheaper than processing new bauxite ore to aluminum.
Thank you very much Thrasymachus! A good cite given in true Doper spirit.
From your post, I seem to understand that there are automated, mechanical devices for separating the top of the can from the rest. I would conclude that a recycling facility would probably not be too worried about having the cans be “pre-separated” by the consumer. I should call a recycling facility to find out. If I have time I’ll do that next week.
I’ve been pulling those tabs off pop cans, beer cans, and any other type of can for seven years now, as I’m a bartender. It’s the least I can do, even if it’s only a penny for every ten I pull off. It gives me something to do when not serving customers. I think if enough people do this (and I know plenty that do - most American Legion clubs, for example) I can see it conceivably adding up.
Making something out of nothing. I can see the logic in that. Even if it’s just a little something.
darvijen, why not save the whole can? That’s even more something out of nothing.