Before I get into the details and my cleaning process - here is a before and after picture of the steel! Looks good right?! Let me explain what I know.

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The “after” picture was taken on the final cleaning step as I was drying the steel. This doesn’t yet have any seasoning. Immediately after I did a coat of seasoning. (seasoned pictures of steel at bottom of article)

Pizza steels! Superior to stones. They transfer heat quicker and retain heat better. They’re heavy and expensive to buy. I’d recommend buying one that’s pre seasoned but if you’re like me and already bought one and wondering what to do follow my steps. I spent about 2 weeks figuring out and scouring the internet how to clean the thing. I digged into MSDS sheets to understand mill scale toxicity, the chemistry of vinegar with Mill Scale and steel. I’ve read about 20 different guides and came up with this recipe for myself. I finally got mine seasoned last night and I’ve got to say it came out AWESOME because I did all this research before hand. I don’t want to get into all the science but this is a great starting point at least for seasoning science.

Seasoning: This article someone did a pretty thorough study on seasoning pans and took measurements with a SEM (scanning electron microscope) and AFM (atomic force microscope) to determine the optimal seasoning technique to achieve the right contact angle for good hydrophobicity.

Mill Scale removal: In this video this guy compares vinegar to Muriatic acid for removing mill scale. For my steel the vinegar took a long time because vinegar is week and the mill scale was very thick.

Now let’s get started

Things you’ll need

  • Large container/tub to fit the piece of steel in and submerge with vinegar
  • Vinegar: enough to completely submerge the steel with about 1/4 inch of room to spare. My bucket needed 1 Gallon so I bought 4 gallons for multiple cleaning cycles. Total cost ~ 9$ ish dollars at my local Walmart
  • Metal Wire Brush
  • Scotch Brite scouring pad.
  • Baking Soda: Just bought 1 little box.
  • Paper towels: 1 full roll should be good enough.
  • Some rubber cleaning gloves: mill scale and iron oxide is very resinous and sticky. you’ll want to use gloves when cleaning otherwise you’ll wash your hands A LOT.

The first couple steps will be repeated more than 1 time to really clean the steel. So from high level we soak, scrub, and clean and repeat until we see raw steel.

Removing mill scale and cleaning

Step 1

Soak the steel in the container with enough vinegar. The steel should NOT be exposed to air as it will rust. 24 - 48 Hours should be good for a first pass. The cooking vinegar is diluted to 5% vinegar. Cleaning vinegar is usually 10% and can speed up the process. The REALLY good vinegar (industrial grade 30% and up) is kinda expensive though so I didn’t mind buying the cheaper stuff and waiting.

Contrary to what others say online - you can soak this for a LONG time without detrimental effect to the steel it won’t hurt it if it’s there for a few days. The acid in common household vinegar is diluted enough and not strong enough to really degrade the steel once it’s down to the raw steel. If you soaked it for months that’s a different story and the acid will take effect on the steel. Checkout this video where someone soaked rusted tools for 18 months in vinegar.

Step 2

Clean with Scotch Brite! Rub down that surface with scotch brite as good as you can. Then switch to using a steel brush. This process could take up to 30 minutes on both sides to really begin to remove a lot of that mill scale.

Step 3

Remove the steel from the vinegar and rinse with COLD water for about 30 seconds to 1 minute to remove the vinegar and particulates. Then rub it down with a damp paper towel that was soaked with cold water and baking soda. The baking soda will neutralize the acid and the cold water will slow down flash rust formation. Then dry with paper towels. Like really dry it. The paper towels will probably come off dirty the first pass at this and that’s okay. You want to do this part as fast as possible otherwise you’ll flash rust and contaminate the next vinegar bath. On the final “cycle” of cleaning the paper towels might still look a little gray but at this point that should be okay. I believe that’s miniscule amounts of FeO (iron oxide). We really just want to remove the mill scale and get down to raw steel.

Proceed with the steps in the below paragraph only if it’s the final “cycle” and your steel is looking ready.

Step 4

Dump that vinegar! Don’t do it down the drain that could rust the pipes. I poured mine back into vinegar bottles and dumped them outside.

Clean your bucket/tub/container as good as you can so there isn’t any mill scale or grime left in it to contaminate the next vinegar bath.

Step 5

I repeated steps 1 -4 MULTIPLE times. It took me almost a full week and 4 cycles in separate vinegar baths to get clean looking steel. The steel should look like the color of stainless steel by the time you’ve finished removing all the mill scale.

Seasoning

Oven should be already preheated to 450F by the time you’re drying the steel from the final vinegar bath. (Some people do a preheat step at 200F by heating the steel before putting oil on. I did the first seasoning this way as I wanted to get the oil on ASAP to prevent rust so I went straight to a high temp.)

Now you’re ready to season get your favorite seasoning oil. I used grapeseed.

Very very lightly but quickly apply oil to all parts of the steel. You want a super light coat. Then use a dry paper to remove as much excess oil as possible. You really want to pretend you’re trying to wipe all the oil off. The oil will get into the pours of the steel and you don’t want too much.

Throw that bad boy in the oven for about an hour! Then turn off the oven and let completely cool.

Now you season some more:

Preheat oven to 200F with the steel inside. After about 30 min after the oven reaches temp remove the steel and use the same oiling process. Wipe with oil/remove as much excess. Put the steel back inside the oven and bump oven to 450F. Do this 3 extra times.

The steel should be seasoned by now. This is a long process. I’d recommend just buying a pre seasoned steel. I only did this because I already had steel that I bought and didn’t realize how tedious it was. Anyways now my steel is done and looks beautiful and I’m excited for pizza.

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Seasoned steel after 4 coats of seasoning illuminated under natural sunlight and then warm light ~ 3000K . It looks almost golden in the sun!

Thanks for reading this article. I spent a lot of time researching around what to do safely and correctly and hope that all this information in this article will help someone else.