Cleaning Digiboil

[Sundy]

I boiled water for an hour to find my evaporation rate. I then put in PBW and fresh water and heated it up to clean manufacturing oils off the vessel. The PBW has discolored the stainless. What should I use to polish the stainless steel?

 

[Pappers_]

I think it is supposed to change colors when you use it, right? I can't think what that process is called, if it is even a thing LOL.

In any case, I found this thread here on HBT that might help you out Question about Stainless Steel, Discoloration, Hard Water Buildup, and Passivating

 

[Sundy]

It's called passivation. I watched this cat on Youtube and the inside of his Digiboil was shining like a diamond in a goat's ass. I am thinking about a low abrasive cleaner like Bar Keepers Friend.

 

[Pappers_]

It's called passivation. I watched this cat on Youtube and the inside of his Digiboil was shining like a diamond in a goat's ass. I am thinking about a low abrasive cleaner like Bar Keepers Friend.

Again, going from some kind of hazy memory, isn't passivation supposed to provide a needed, or at least useful, barrier? Not to dissuade you from getting your stuff shiny, just raising a point. With my stainless steel, I use pbw and a scrubby sponge, never use an abrasive on it, but that's just my experience.

 

[Sundy]

I just restored my old 3 gallon kettle for my small batches. It had some scorching and discoloration similar to what I see in your pictures.

First, I soaked the kettle in a warm and strong vinegar solution (1 liter vinegar and filled to the top with water). I put a touch of detergent in this and rubbed the foam on the sides. Doesn't need to be terribly hot. That should help to loosen up some of the stuff at the bottom, and I use a soft white scrubby after to remove the loosened debris. I will rinse and then hit it with a strong PBW solution at 150F... at the top end of the heat recommendation. I let this cool to room temperature and then repeat the slight scrubbing, cold water rinse. This removed most of the discoloration, and in my pan, the water got a tiny bit green. At this point, I used Barkeepers Friend, a soft clothe for scrubbing, and gave the pot a solid inside and outside polishing. BKF will also help to passivate if you follow the instructions. You probably need less than you think. After you are happy with the results, then rinse several times.

Finally I use Star San at 1 oz to 1 gallon of RO water to passivate the stainless - you can also use Sani Clean at 2 oz to 1 gallon. I apply the solution with a soft sponge and let it air dry a few hours. Rinse, repeat the process until happy with the result. Make sure you rinse this thoroughly and towel dry until the towel comes away clean.

You would be using both caustic (PBW) and acidic (Star San, vinegar) products. Wear appropriate gloves and eye protection, and I would suggest doing this outside if possible.

I misspoke, BarKeepsers Friend is not mildly abrasive. It is oxalic acid and promotes passivation as mentioned in the thread you referenced.