Aluminum Mash Tun?

[Nightbiker]

I need a bigger MLT (mine is only a 9gallon stainless) and after getting over the shock from the cost of stainless 'tuns (not to mention those big round coolers -boy are they PROUD of their product!) I ran across some (very) large aluminum cooking pots that my local 'mostly mexican' grocery store keeps in stock -these things are pretty inexpensive and built LARGE (I guess their clientele must have some really large families, or they cook for a lot of people).
I know the ongoing debate about aluminum boil kettles (and I've never had a problem with them, I used to use one until I get a keg converted) -but a mash tun could be an animal of a different color. My interest in the pots is that they are a bit wider than the usual converted keg -so the mash wouldn't be as deep, and I'd expect it would have a more even consistency in the mash (and a bit easier to clean) -but I know mash PH tends to get down to just above 5, which is reasonably acidic -and wondered if that might cause my beer to have a 'metallic' flavoring -which I don't find desirable in the slightest). Has anyone made their MLT out of aluminum? If you did, how did it work out? My rig is an HERMIS so no direct heat to the mash tun, but the water recirculates continuously. My heat exchanger is in my HLT, and all the piping is (as usual) copper with brass fittings.
The false bottom would probably be made from stainless, however. But before pricing that out, I wanted some advice regarding the 'tun.

 

[earwig]

Maybe check out Craigs list for a used cooler? I got a great cooler at a 4H rummage sale for 5 bux. I can't comment on the aluminum subject, I know nothing about it sorry.

 

[Transamguy77]

When I started AG I was doing BIAB in a 7.5 gallon aluminum turkey fryer and have no off flavors at all, you will be fine. I would still be doing it that way if I had not gotten a good deal on kegs and converted them.

 

[Nightbiker]

Thanks for the input! If anyone does have experience using aluminum for a mash tun, please speak up! If I (finally) break down and just do it, I'll post results (and pray to the Beer Gods that I don't regret the conversion) -I did get (the other day) a donor half-keg from a friend who found it in a yard sale (you would think they would have just turned it back in for the deposit money -worth more than they got for it -but their loss is my potential gain). I'd really like a wider, shorter 'can' though -but I'll have to have a few beers and think it through. Those buggers are tough to cut through (I don't have any friends with plasma torches).

 

[Transamguy77]

Thanks for the input! If anyone does have experience using aluminum for a mash tun, please speak up! If I (finally) break down and just do it, I'll post results (and pray to the Beer Gods that I don't regret the conversion) -I did get (the other day) a donor half-keg from a friend who found it in a yard sale (you would think they would have just turned it back in for the deposit money -worth more than they got for it -but their loss is my potential gain). I'd really like a wider, shorter 'can' though -but I'll have to have a few beers and think it through. Those buggers are tough to cut through (I don't have any friends with plasma torches).

A grinder or a air powered cut off tool works too, I used the air tool to cut off all 3 tops. If you have that you could make that into your mash tun and not worry about using an aluminum one.

 

[helibrewer]

If an aluminum kettle is ok (which it is), then an aluminum MLT will be fine too. Contact time is about the same and the temperature is lower. Would you be concerned about simmering stew for a few hours on your stove in an aluminum pot?

 

[brewguyver]

Thanks for the input! If anyone does have experience using aluminum for a mash tun, please speak up!

The only negative I can see is that aluminum is more conductive than stainless, so you'd lose temps faster during the mash. However, since you're doing HERMS you can insulate the hell out of it so it shouldn't matter.

 

[Ezekielsays]

I've been using an aluminum mash tun for about a year and a half now, and haven't noticed any metallic off flavors from it. I've been pretty happy with it overall.

As stated, they don't hold heat as well add some other materials. I made a double layer reflectix "jacket"for mine, held on with Velcro strips so it is easily removable for cleaning. I have no issues with losing heat (usually 1 degree drop through the mash time) though during winter brews I usually add an old blanket. MN can get cold sometimes.