SS pot discoloring, anything to worry about?

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realestwhiteboy
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SS pot discoloring, anything to worry about?

Post by realestwhiteboy »

I finally got all of my SS parts together, put it all together, did a vinegar run ... and saw these spots form after.

I'm using an electric hotplate for the heat source, and this is the spot centered over the heat (of course). I'm thinking it is normal discoloration due to the heat, but wanted a more experienced opinion before I used this pot to mash in for the 1st time tomorrow.

I expected the blues to form over the heat, but wasn't expecting the browns and reds, so wanted to make sure I wasn't making poison tomorrow. :D
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StillerBoy
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Re: SS pot discoloring, anything to worry about?

Post by StillerBoy »

Looks like you run low on liquid, with extremely high power, and the pot bottom is not that thick..

Just rinse it with some vinegar and some ss scrubby..

She' be good as new..

Mars
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realestwhiteboy
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Re: SS pot discoloring, anything to worry about?

Post by realestwhiteboy »

StillerBoy wrote: Thu Apr 15, 2021 5:19 pm Looks like you run low on liquid, with extremely high power, and the pot bottom is not that thick..

Just rinse it with some vinegar and some ss scrubby..

She' be good as new..

Mars
It's an 8 gallon pot, and I had 3-4 gallons in it, ran a little less than a gallon out and ended with a little a little over 2.5 gallons in the pot at the end. But the pot is thinner than I'd like & I did run high temp today to push the vinegar through fast (didn't have the time to be patient with the vinegar run today), so it may be that I needed to load it a little more than I did or run a little slower (or both).

I'm not too worried about the color, as long as it's not damaging to the pot or the product I run through, but will give it a little elbow grease before I do anything tomorrow. :)

Thanks for the reply. :thumbup:
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Deplorable
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Re: SS pot discoloring, anything to worry about?

Post by Deplorable »

Scrub it with Barkeepers Friend.
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Kindafrench
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Re: SS pot discoloring, anything to worry about?

Post by Kindafrench »

Scrub it off if it get‘s too thick or getting rough. It might reduce heat transfer if it‘s really getting a serious layer. As far as I know, it‘s only minerals from whatever you boil in the pot. It‘s no evil stuff.
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RC Al
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Re: SS pot discoloring, anything to worry about?

Post by RC Al »

The blue discoloration is the SS changing temper, the lighter spots would be from where it was cooler from nucleation points
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Demy
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Re: SS pot discoloring, anything to worry about?

Post by Demy »

Nothing to worry about. The purple part is due to very intense heat, those white spots are water limestone. Clean with vinegar and water, once cleaned, use a sponge slightly abrasive (like the one for dishes) to make it the most polished possible.
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Saltbush Bill
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Re: SS pot discoloring, anything to worry about?

Post by Saltbush Bill »

First time I looked carefully at the photos I didn't enlarge them first time around , second time now and Ive had a good look ......those spots do look kinda weird..never seen Staino do that before.
StillerBoy
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Re: SS pot discoloring, anything to worry about?

Post by StillerBoy »

Deplorable wrote: Thu Apr 15, 2021 6:36 pm Scrub it with Barkeepers Friend.
Yeah that a very product to have on hand if working with ss..

A little vinegar will do the same..

Mars
" I know quite certainly that I myself have no special talent. Curiosity, Obsession and dogged endurance, combined with self-criticism, have brought me to my knowledge and understanding "

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Yummyrum
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Re: SS pot discoloring, anything to worry about?

Post by Yummyrum »

Is that pic the inside of your pot or the bum .

I’m gonna guess its the Bum .
I wouldn’t worry a bit about it ... should see what mine looks like after a High pressure gas burner has Scorched the crap out of it on a stripping run .

Even my pissy thin 68 litre wash tube BOP with a furnace flame under it won’t have any discolouration on the inside where the liquid is .

Liquid will clamp the metal surface temp close to its boil temperature so even if the flames ( or element underneath ) are at several hundred °C , the surface of the BOT metal in contact with the liquid will be less than 100°C and way below discolouration temp from overheating .

Anyway , don’t worry about it :thumbup:
realestwhiteboy
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Re: SS pot discoloring, anything to worry about?

Post by realestwhiteboy »

Yummyrum wrote: Fri Apr 16, 2021 5:15 am Is that pic the inside of your pot or the bum .

I’m gonna guess its the Bum .
I wouldn’t worry a bit about it ... should see what mine looks like after a High pressure gas burner has Scorched the crap out of it on a stripping run .

Even my pissy thin 68 litre wash tube BOP with a furnace flame under it won’t have any discolouration on the inside where the liquid is .

Liquid will clamp the metal surface temp close to its boil temperature so even if the flames ( or element underneath ) are at several hundred °C , the surface of the BOT metal in contact with the liquid will be less than 100°C and way below discolouration temp from overheating .

Anyway , don’t worry about it :thumbup:
That is the inside of the pot (where the liquid is sitting & touching). The outside bottom of the pot actually looks brand new, no spots or marks or discoloration at all.

To give full details of what I did when these formed:
The pot holds 8 gallons. I used around 3-3.5 gallons of tap water (from the county, not well water) and a little under 1 gallon of white vinegar in the pot. I am heating with an electric burner hotplate. The hotplate has temperature settings, but you can't set the exact temp you want, can only use it's pre-sets (200F, 250F, 320F, 360F). Because I was pressed for time yesterday, I cranked at 360F to quickly get up to 190-200 on my temp at the top of the boiler, then I cut the temp down to 320F (250F on the bottom wasn't heating the liquid to a high enough temp to keep everything going) and distilled a gallon or less of what was was in the boiler and cut the whole thing off. During cleanup, I noticed those spots.

Like mentioned, the bottom is also thin. I bought the the pot online, where it was advertised as having a heavy-duty bottom ... it definitely doesn't. So, between the high heat and think bottom, guessing that is the cause.

I used some elbow grease, white vinegar, and the rough side of the sponge. That seemed to get it all out.

Still concerned about what appears to be machining marks left on the inside of the pot during production. But guessing there is nothing to be done there, and hopefully no worries to be had.
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Birrofilo
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Re: SS pot discoloring, anything to worry about?

Post by Birrofilo »

realestwhiteboy wrote: Fri Apr 16, 2021 8:24 am Still concerned about what appears to be machining marks left on the inside of the pot during production. But guessing there is nothing to be done there, and hopefully no worries to be had.
The machining marks should appear of the same colour of the steel. You can see from the picture a brownish band and the darker spots are also brownish.

Vinegar could easily be the answer IMHO.
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