How to tell aluminum from stainless kegs

[alntdistil]

Not sure where I should have posted this, in the material safety forum or here. I figure it's a pretty novice question so here is probably good. I'm talking to a guy online who's selling some kegs he has sitting in his garage. I know aluminum probably won't work as a boiler but stainless will. I asked him if they were aluminum or stainless and he said he didn't know. How could I (or explain to him) tell the difference? Aluminum is way lighter than stainless but this dude doesn't seem to know what he's talking about here so I'm sure he won't be able to tell from weight unless he had another keg to compare it to. Does it say on the bottom or anywhere on the keg?

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Thanks guys.

[Tater]

http://homedistiller.org/forum/search.p ... mit=Search

[rubber duck]

First try to scratch it, aluminum scratches easily. Next tap it with a hammer aluminum has a real dull sound. I don't know about that style of keg but a normal bud sanky keg weighs something like 16 pounds. Just by looking at the pictures it looks like stainless to me, at least the coors one does.

[rubber duck]

Or you could just do a search.

[rad14701]

The kegs in that picture appear to be stainless steel... I don't think Coors has used aluminum kegs in a very long time...

[alntdistil]

Alright, thanks guys. I was hoping there would be an easier way to tell besides trying to cut it, but I guess I'll have to go over to this strange person's house and ask him if I can try scratching his kegs...

[ScottishBoy]

Mine is stamped SS just before the model number on the top. Mine is a half keg, 50 L and it weighs 31.98 pounds. I would have gotten it for free if it weighed 32 cause thats what I guessed..
Another way to tell is to wrap it firmly on the botton with a medium stick. Most SS kets will make a sound like "kang", whereas most Aluminum ones will make a sound like "poong"

Another way to tell is to simply rub your hand on a polished section for a few minutes and see if it turns blackish from the aluminum oxide.

[ozone39]

hit it with a ball peen hammer. If it bounces it's s.s, it makes a dent it's aluminum.

[LHD]

touch it with a grinder on the rim. If i am not mistaken. Aluminum is non-ferrous and will not spark. Stainless will spark.

[maheel]

just try picking up a keg.....

IMO ally ones weigh very little compared to SS

[Aesgarth]

I could be wrong here, but can you not just stick a magnet on it - aluminum being non magnetic it wont stick, with steel it will...

[Kentucky shinner]

Stainless is not magnetic....your magnet will not stick to stainless

[Husker]

depends on yer magnet. If you have some rare earth stuff, that has a HELL of a grab to them (I have a bunch I harvest from computer HD's), then they do weakly stick to almost all stainless. Yes, it is not highly magnetic attractant, like iron or carbon steel, but it does attract a magnet, some.

The AL kegs will not attract at all.

It is ususally pretty easy to just rub your hand over it (hand not being 'bone' dry). It will turn black from the AL oxides.

The weight is not always a good thing. I have 15.5's that vary from 18lb to 43lb. It all depends upon the gauge. If you find a skirted keg, it is 99.9% chance of being stainless. The only AL ones I have seen, have had weird bungs in them. I think pretty much all of the sanky type are SS. The ones I am familiar with are the older Hamms, and some very old Coors. They tapped on the side. The hams were even wooden (or some composite) bungs in the side, that had 2 holes in it. It was sort of in a little 'sump' divit.

Now, once you see an AL keg, you will know. They are totally different color that SS. The AL ones are whitish, while the SS are silver, often with scratches that show the real SS color.

Here are some AL kegs:

Aluminum kegs

AlKegs.jpg (5.71 KiB) Viewed 18023 times

H.

[Kentucky shinner]

I did not know any magnet would stick to stainless.... I have never seen that.. Guess you learn something everyday..and I have been working with metal all my life.
Thanks for the insight. I did not mean to give anyone missinformation.
KS

[Husker]

Mag will not 'stick' to all forms of SS, but it will have an attraction. There is ZERO attraction to AL. But a weak on to 'many' SS's if they have been machined. The rare earth magnets I get form HD's are STRONG. You do not want ot get your finger (or some meat on it), between 2 of them suckers. They will smash the heck out of it, and if you are lucky, all you will get is a blood blister.

H.

[cob]

i have two anhauser busch kegs one half keg and one quarter. took some rare earth magnets to the shop to test with. one hdd mag and a stack of harbor freight 10 for $1.99s
the magnets performed equaly, but the kegs did not one had noticable attraction on the rings but barely noticable on the barrel. the other keg was noticable on the barrel but barely on the rings.

neodymium magnets are extremely dangerous as husker noted earlier, the small ones have been ingested by toddlers and displaced the bowel causing death. the bigger ones can pinch off an adult finger or crush a hand. cob

[Husker]

The 'barely noticeable' is all you need. AL will have absolutely NO attraction at all. As you have also seen, there will be parts of the keg that have stronger attraction. As long as there is attraction, and the material is all put together (welded or spun, however, the hell they make them), then you have a SS unit. If the entire thing has ZERO mag attraction, the metal looks 'different', then you likely have an AL.

Also, I believe that if a keg has a skirt, it is a SS one. I have never seen AL other than the fat-bob type.

H.

[cob]

crutial point were is if you are not using neodiymium magnets to test with you will get no result, alnico and feric oxide magnets won't give you "that faintest hint" of attraction. cob

[rad14701]

Tape any strong magnet to a piece of thread or string and dangle it next to the keg... If it's stainless steel it should drift towards the keg... If it is aluminum it will hang straight down...

[Kentucky shinner]

your smarter than you look RAd.. that is a hell of a good idea... quite the thinker

[Husker]

Good tip rad. I have become used to being able to detect 'weak' magnetic pull, since I buy a lot of scrap jewelry (for the gold). There is a lot of stuff that is covered (or even colored) stainless, that has a weak mag attraction. It is pretty easy when checking a necklace. Just dangle the necklace down, hold the magnet close, but not close to a clasp (which I know has steel springs in it), and if the necklace moves, I do not buy it. For other things, you have to hold magnet, and get used to the slight 'tug'. Same for the keg.

But the tip of the string is ideal. The attraction may not be enough to attach the magnet (i.e. less attraction than weight of magnet), but it is enough to 'move' the magnet closer.

Again, repeated before, but will do so again. AL will have absolutely no attraction at all. It does not matter if you use the strongest magnet around. It will not attract.

But cob may be right, that weaker magnets (weaker than the rare earth jobs that are super strong), may not have enough pull to distinguish all forms of SS. I also can not assure everyone that there is NOT forms of SS that have no attraction to these these super strong magnets. It is just that I have not seen any that do not (even surgical instruments).

H.

[The Baker]

I did not know any magnet would stick to stainless.... I have never seen that.. Guess you learn something everyday..and I have been working with metal all my life.
Thanks for the insight. I did not mean to give anyone missinformation.
KS

Yeah, that's how cooks can use magnetic strips on the wall as a rack for their stainless knives, I guess. Always looks wrong to me but it works.

[NcHooch]

muriatic acid will dissolve aluminum, but has no effect on stainless.

(wear yer safety glasses n gloves)
NChooch

[germag]

Look on top of the keg. There are usually numbers and letters on there. I have a Coors keg that is stamped 304L. 304L is a grade of stainless steel. If you see that stamp it is stainless. Other grades of stainless are: 303, 304, 316, 316L, 2205, 904L. Good luck!

[memetic]

crutial point were is if you are not using neodiymium magnets to test with you will get no result, alnico and feric oxide magnets won't give you "that faintest hint" of attraction. cob

That, and not all SS is the same; some has higher amounts of nickel and some less. Higher nickel equals less magnetic attraction. So you got other factors here besides your magnet.