Uh-Oh - (scorched kettle)

Well, my homebrew club did a steinbier (use hot granite rocks to produce the boil) Sunday. I was adamant when we started planning that we would not be using my kettle as it is aluminum (too easy to dent with granite rocks being put into it). The brew had to be done at my house because I have the room for a fire that they don't. I several times asked what pot were we using and never got an answer. Day came so I filled my kettle up with top off water and boiled it the night before thinking even more reason not to use my kettle.

Guess what. They didn't bring a kettle and we had to use mine. Small dent in one side and the bottom doesn't appear to be flat anymore. Neither of these are too big of a deal (although that is the reason I didn't think my kettle was a good idea). The big deal is this:

That's about a dinner plate sized scorch. The batch was 11 gallon boil with 33# of lme and some steeping grains. We dilluted out to 4-five gallon batches.

Yes I am pretty pissed, I don't have a lot of money since my layoff and these guys sandbagged me and now I have the damage to deal with.

Moral of the story: When you know you shouldn't do something and you don't want to use your equipment for something, stand your ground and don't be pushed into it. I'd rather brew another day or not at all then to risk ruining my equipment again.

I've got some baking soda paste on it now and I scraped off a dollar sized area in the middle with a wooden spoon. Hopefully there is something I can try to help scrape the rest off. Any suggestions?

TIA

PS I did a search and didn't find anything, although I am hot under the collar still so I may have been impeded in my search skills. Sorry if I overlooked it.

Nothing wrong with aluminum. I've been using nothing but for years. I think what happened here is that you did an extract batch and put the heat to it before it was fully mixed. The heavy LME sat on the bottom and scorched. Sorry for your loss.

Does it really have to be cleaned off?

Yah, I don't get it. Why'd your aluminum scorch? If on the other hand, you expected it to scorch .... why the hell would someone else volunteer their equipment for that?

-BigCask

They decided to use a turkey fryer basket to put the rocks in. I think that extract settled down under it and it scorched. 33# LME in 11 gallons of water is pretty concentrated.

PLANNING. That's what happened. They aren't very good at it. I raised questions but nobody seemed interested in figuring out answers. It is ultimately my fault for not saying "No." Too many unknown variables for my comfort.

Any experience in getting scorches out of aluminum?

And I have no issues with aluminum. I am careful not to toss it around and keep my oxidized layer by not scratching it and I don't use abrasives or caustics to clean. I think the concentration was just pretty high. Then scalding rocks pinched the basket against the kettle and it scorched.

"For cleaning aluminium objects, the use of sodium bicarbonate is discouraged as it attacks the thin unreactive protective oxide layer of this otherwise very reactive metal."

Eep, rinsed that out.

I've boiled lemon juice in the bottom of stainless steel to get rid of scorching, it worked well. I don't know how that would affect aluminum though. I've also heard dishwasher soap works well for stainless but haven't tried it.

I would be more pissed about the dents and it not sitting flat than the scorching myself.

Oxyclean? .

Looks like a job for 3M abrasive pads to me. Boil some water in the kettle afterward to rejuvenate the oxide layer.

rcm_rx7 said:

I've boiled lemon juice in the bottom of stainless steel to get rid of scorching, it worked well. I don't know how that would affect aluminum though. I've also heard dishwasher soap works well for stainless but haven't tried it.

I would be more pissed about the dents and it not sitting flat than the scorching myself.

Click to expand...

The dent is pretty minor, inch or so, not very deep, hardly noticeable. The sitting flat isn't bad either, probably a few cm concave out at the bottom. I should be able to push that in easily, if not leave it for the whirlpool to settle in.

I think the lemon juice would be a caustic on aluminum.

Yuri_Rage said:

Looks like a job for 3M abrasive pads to me. Boil some water in the kettle afterward to rejuvenate the oxide layer.

Click to expand...

I'll give that shot. Think some dishwasher detergent or oxiclean in a couple inches of water boiled in the kettle then use the pads as soon as it is cool enough?

What brew club brews batches with LME?? Time to give AG a shot lol. Soak the sucker in Oxyclean for a day or two and get a scotchbrite pad on it.

zanemoseley said:

What brew club brews batches with LME?? Time to give AG a shot lol. Soak the sucker in Oxyclean for a day or two and get a scotchbrite pad on it.

Click to expand...

A brew club doing a 20 gallon batch and none of us has AG equipment large enough for that. LME over DME because of the availability of 33# jerry cans. And with steinbier you already have a considerable amount of time involved and extract shaves a ton of time off.

I'll give the oxyclean soak a shot until I can get some water into it to boil.

I know bon-ami and the scrubby side of a sponge has cleaned about anything for me. You could give that a try. It really is an AWESOME cleaner. GL!

Yuri_Rage said:

Looks like a job for 3M abrasive pads to me. Boil some water in the kettle afterward to rejuvenate the oxide layer.

Click to expand...

This is all you need to do,
On thing nice about aluminum, no matter what, It will scrub to bare metal quite easily. I recently bought a used 20 gal alum kettle that looked far, far worse than that! A few minutes w/ an abrasive scrubbie...like new!

No worries, that will come right off and the oxide layer will return.

Use the green 3M scotchbrite, (or more abrasive, if you can get it)..the blue ones won't do crap. The really good 3M scrubbies will chew THROUGH your pot with no problem, so that scorching should be no issue. Just go til you see silver, then boil water to rebuild oxides...

There is a Brew Strong episode "Sanitation" where they had the guy from Five Star on and if I recall he talked about using his chemicals on things like aluminum...might be worth a listen. And even then I would think that if you needed to use some PBW this one time your kettle will be just fine, just not something you want to regularly do to an aluminum kettle.

I have used oxiclean to get rid of scorches before with great success. I am pretty sure though if you use oxi on aluminum you have to boil afterward to get the oxide layer back

Pounding the thing back into shape may - or not - crack it.
You'd not likely ever get it factory flat.
The shape of the bottom is not terribly relevant if you are using a propane burner or gas stove.

On the flip side of all things negative:
I have often contemplated how I could Use a 20 ton hydraulic jack (I have two) and some pre-made concrete forms to make the bottom of a BK round to collect the whirlfloc settlings.

Maybe the trick is to heat the sucker up and lay the bowl shaped concrete in the base and wait? Sort of like they do when slumping glass.

I haven't used it on aluminum, but I did scorch some mash on the bottom of my stainless steel decoction pot. Straight starsan (use gloves) allowed to sit for 30 minutes did a great job of getting it off.

so you put rocks in your beer? interesting

It was pretty neat how vigorous a boil we got from the rocks.

Lots more photos on my blog.

link to blog?

In my sig. The Homesteading one.

Wow, got a lot off with the scrubby. Arm is about to fall off, so we'll give it a go tomorrow. Thanks for the advice, looks like I may be able to get it up.

Videos being added as we speak. Love the noise the first rock made. Scared the guys with the "Boom" I yelled too.

Sorry about the compressor noise but it was necessary. Kept the boilovers at bay as well as cleaned off the rocks.

I feel sOOoOOOooOOooo stoopit.
I've solved this exact scorching problem. Electric Hand Drill and wire brush.
dunno how I managed to not think of that.
Must be all the beer.

If the pot is aluminum use any wire brush you please. You'll have to re oxidize it but that will take all of 20 minutes
If it's SST use brass brushes only. Carbon steel can slough off onto SST and start rust pits.

You don't have to worry about pitting the aluminum?

Daddymem said:

You don't have to worry about pitting the aluminum?

Click to expand...

Not with a wire brush you don't.
And aluminum will not pick up carbon steel and start to rust. Stainless can and once it starts the only way to stop it is to passivate it.

Pitting in aluminum will be an issue if you use acids or strong bases on it in a careless manner or an overly strong solution. But mechanical abrasion will do nothing to harm the metal unless the person loses his mind three stooges style and grinds a hole in it.

Just keep scrubbing, scrubbing, scrubbing. Getting there.

I wish I could join a group. I think youre lucky. There is a local group, but they meet once a month on a night I'm busy.

Oven cleaner?

I sprayed that on a baked on broiler once. Seemed to work fairly well.

Do not use oven cleaner on aluminum. Oven cleaner is caustic (I think it contains lye) and will severely corrode aluminum. Trust me on this. Been there. I would use an offset grinder and a medium Gator pad to buff it off mechanically. I would only use cleaning agents designed specifically for aluminum.