Rust In Aluminum Kettle

[charliedvrs]

So a few weeks ago I was heating my water up to mash temp in my 10 gallon aluminum kettle, when a bit of a family emergency came up. I left the water in the kettle with a metal grate at the bottom I use to keep my grain bag from scorching (brew in a bag), thinking I would come back to it later that evening or the next day. The small emergency turned into a much bigger one and I wasn't able to brew again for another two weeks, and completely forgot that about 4 gallons of water had been sitting in my kettle. When I came back to it there were several small spots of rust where the grate contacted the kettle, as well as a slight bit of visible rust along the bottom. I included some pictures below to give an idea of the amount. My question: is my kettle toast? I searched around and didn't see any threads specifically about aluminum kettles. If I'm going to be chancing wasting a batch with metallic off flavors I'd rather just go out and purchase a new one - leaving my prior to Rust In Peace. Though, if someone has a good, proven idea how to remove the rust without damaging the kettle I would LOVE to save the money on a new one.

 

[Diver165]

Have you tried some steel wool or a scrub pad?

 

[phoenixs4r]

Ita fine. It will probably come off with a kitchen sponge. I wouldnt use steel wool or any other steel based product to remove it.

 

[charliedvrs]

Have you tried some steel wool or a scrub pad?

Haven't yet, that was my first thought but wanted to check here first to make sure that wouldn't cause anymore damage as far as wearing away at the bottom of the kettle. I've read lots of different tips from using aluminum foil to onion to some kind of toothpaste based cleaner. Just not sure how any of these methods would effect the kettle with the acidic wort as far as brewing is concerned, also with the consideration that I'm using the kettle to mash as well as boil in.

 

[djfriesen]

You can always scrape it off and then re-oxidize your pot. That seems the wrong color for aluminum oxide, though. It's coming from your grate, I bet. I would find a stanless grate or use some kind of nested strainer pot for the mash if I was you. That stuff's gonna come right back as soon as you use the grate again.

 

[heckels]

Maybe use a little clr? Just give it a good rinse after...

 

[kh54s10]

Scrub it off with something. A Scotchbrite pad or something even steel wool. Then wash it well. After that boil some water in the pot to get an oxidation layer built up again.

That should do it.

 

[JRems]

I had a similar problem with a used aluminum pot I bought. Scrub it until it's shiny with BKF then just reoxidize it by boiling water for an hour.

 

[stux]

Just scrub it bright, then boil some water for a bit if you want

 

[Bobby_M]

That's not the aluminum rusting but it's a rust stain from the cheap stainless they used in that grating. Actually, it looks like the stainless wasn't re-passivated after the welding. Try to clean up the rust on the grate as best you can and put some Bar Keepers Friend paste on those areas. On the aluminum, just scrub it off with the back of a kitchen sponge.

 

[charliedvrs]

Thanks for the help guys. Knew the grate was the culprit, going to try and find an alternative as djfriesen suggested. Going to get scraping away at the rust today.

 

[Diver165]

Haven't yet, that was my first thought but wanted to check here first to make sure that wouldn't cause anymore damage as far as wearing away at the bottom of the kettle. I've read lots of different tips from using aluminum foil to onion to some kind of toothpaste based cleaner. Just not sure how any of these methods would effect the kettle with the acidic wort as far as brewing is concerned, also with the consideration that I'm using the kettle to mash as well as boil in.

If you wear the bottom of that pot down enough with steel wool that you damage or weaken it remind me not to shake hands with you. You'll probably tear my arm off LOL.