Pursuit of leopard spots and light airy crust

[johnamus]

I picked up the 3/4 inch steel plate .  Upon picking it up I was disappointed to see both sides were filled with rust  .  I asked the guy at the warehouse about it and he said that "is how they usually look".  Since the metal supplier is in the business of selling pieces of steel and not pizza baking surfaces I let it slide.  Any opinions on the rust? i.e. is this something that can just be grinded out with an orbital sander, or is this a gamechanger?  One side is better than the other (looking at the photos, the side with the supplier's name on it is the good side).

Either way this plate is a heavy mutha, tipping the scales at over 40 lbs I knew it was going to be around this weight before I picked it up, but a theoretical 40lb steel plate doesn't quite have the same impact as the genuine article.  Maneuvering this in and out of the oven takes some strength!  I purchased 4 pieces of 1/2 inch steel tubing to support the plate in the oven, and these pieces do a great job of preventing any bowing by the oven rack.  I highly recommend this as an oven reinforcement strategy.

I'll wait to hear your opinions about the rust situation before attempting a bake.  Either way, I'm $90 invested and I'm definitely going to give it a shot, if nothing else I can always bake a few throw-away pies in the name of science!

[johnamus]

I also picked up some Caputo 00 flour at DiGregorio's.  It's a great old-fashioned neighborhood market that I hope to revisit soon.  The market stocked a bunch of small relabeled bags of "Caputo" "00" at around $1 a pound, I guess I'll take their word that it is actually Caputo. There also isn't an expiration date on the bags, but the market was extremely busy so I think it's safe to assume the flour is relatively fresh.  There was another bag of 00 with retail packaging but I didn't recognize the brand.

[johnamus]

It looks like "Evapo Rust" is exactly what I am looking for.  It should remove the rust without leaving the scratches of an orbital sander.

http://www.evapo-rust.com/

https://www.amazon.com/dp/B001BNZGY0/?tag=pmak-20

[buceriasdon]

Me, I'd pickup a round paint stripper pad, 3M brand in the paint dept. of the box stores, that can be chucked up in a drill, goggles, gloves and go at it. They are black with a 1/4" shank. Since I recommend seasoning the one side the scratches are a none issue. I doubt you can get all the rust off if deeply pitted but the seasoning will seal it off in any case. Anyways, that's what I have done.
Don

It looks like "Evapo Rust" is exactly what I am looking for.  It should remove the rust without leaving the scratches of an orbital sander.

http://www.evapo-rust.com/

https://www.amazon.com/dp/B001BNZGY0/?tag=pmak-20

[scott123]

Here's a couple photos of my oven's temperature sensor.

It's tricky to tell from the photo, but is the probe right smack dab in the middle of the forking broiler element?  Could they possibly get the probe any closer to the broiler?  No wonder why your broiler won't stay on for long.

That being said, I'm 99% certain that you can remove that bottom screw, which will then allow you to pull the probe out (there will be excess wire) and possibly even set it on the shelf below the plate. With the plate shielding the probe, the broiler will stay on for the whole bake. When you're done, you should be able to push the wire back in, reattach the screw and it will be as good as new.

[Jet_deck]

My minimalist approach to removing the rust (if it is not pitted deeply) would be to wipe it down with vegtable or olive oil and put it in the oven at high temps for an hour or so.  If it doesn't look better, do it again.

[Jet_deck]

You need to knock the slag off of the plate before you cook on it. 

[scott123]

There's a common belief that once steel or iron begins to rust, unless you remove all the rust, it will continue.  This being said, I've known lots of people that have inherited rusty iron pans, given them a light sanding, seasoned them and used them for years.

Now, in this particular scenario, where the plate is this close to the broiler, I'm relatively certain that the surface temps will hit sufficient temperatures to cook off any seasoning.  I'm not 100% certain that a little bit of embedded rust on a lightly sanded, unseasoned surface would be the end of the world, but, since I've never tried it, I'd probably go the extra mile and remove the rust.

If the rust wasn't deep, I'd sand by hand, using a sanding block. Maybe it's just me, but I feel like I can maintain a flatter surface using a sanding block than an orbital sander. As far as the scratches left by sanding go... I don't think they're a big deal.  As long as you get the rust off, that's all that matters.

The evapo-rust just looks like an expensive mild acid.  If the rust was moderately deep, I would probably just use Naval Jelly, rinsing it carefully and baking it quickly to hopefully prevent embrittlement, although, on a hunk of steel this size, I kind of doubt embrittlement would make any difference. 

If the rust was especially deep and the surface was pitted, I might opt for something like

Rust Removal using Electrolysis

One benefit of electrolysis is that it should tint the surface black, which would be good for heat absorption, although not completely necessary.

[scott123]

I also picked up some Caputo 00 flour at DiGregorio's.

I hate to say it, but Caputo makes a variety of 00 flours, many of which are unsuitable for pizza.  The 00 designation only defines the size of the grind, not the protein content.  You can have low protein 00 flour that's suitable for pasta, but not pizza.  The only way to know for certain is to have the bag in front of you- Caputo pizzeria flour will have a picture of a pizza on the bag.

[buceriasdon]

Rust is simply oxidized iron, it's just another form of iron, called iron or red oxide, makes sense,huh? Seasoning as one would season a cast iron skillet, or a blue(carbon) steel pizza pan or a carbon steel wok occurs at an atomic level, the oil bonds with the iron atoms and seals the surface making it difficult for free oxygen molecules to enter and cause the conversion known as rust.
Don

[scott123]

Don, according to this page here:

http://www.cookingforengineers.com/article/50/Smoke-Points-of-Various-Fats

the cooking oil with the highest smoke point is avocado, at 520 F.

Seasoning will not survive at the temperatures we're talking about here.

[Tscarborough]

Food safe mineral oil should work.

[johnamus]

I can't vouch for its legitimacy, but this article http://sherylcanter.com/wordpress/2010/01/a-science-based-technique-for-seasoning-cast-iron/ recommends using a drying oil such as flax seed oil.  The article recommends heating the cooking surface above the smoke point so that polymerization occurs.

Scott,

• I share your uncertainty regarding the flour I purchased. The good news is that the shelf had a cutout from a Caputo pizzeria flour box taped to the front of it. 
• The temp probe is positioned right next to the broiler element, I removed the screw and pulled it out as far as it would go (picture attached to this post). Do you think the wire insulation can withstand being so close to the broiler?  This got me thinking about crimping on an extra 3 feet of properly insulated wire and leaving the probe outside the oven.  Aside from the inherent safety concerns, this method would guarantee a hot oven!

Jet-deck,
Yeah that slag is nasty. Its on the bottom side but I'll have to grind it off before it scratches up my oven.

[buceriasdon]

My experience has been you have to get over 600 degrees to burn off the seasoning. It can be done of course, I've done it and measured the point at which the black starts to turn gray. I still say season the plate.
Don

[johnamus]

Don,

What's your seasoning procedure?

[buceriasdon]

I'm a light coat of Crisco, stick in the oven, heat up to 400, hold for thrity minutes, let cool down kinda guy.
Don

Don,

What's your seasoning procedure?

[scott123]

Don, with the proximity of John's steel plate to his broiler, it's guaranteed the surface of his stone will exceed 600.  It won't be a sustained 600, but it will be long enough to burn off any seasoning.

Tom, mineral oil won't polymerize/harden into a baking surface, ie, it will go straight from liquid to smoke.  The pizza will just soak up the mineral oil as it bakes on the plate.  Mineral oil is only good for extended storage:

http://ths.gardenweb.com/forums/load/cooking/msg1021083911510.html

John, that's great news about the pizzeria flour box cutout in front of the flour bags.  The insulation on the probe wire, on the other hand, is really bumming me out.  Most probes have thick, uninsulated wire behind the wall.  I really don't see the insulation surviving the heat from the broiler element.  I don't see how you have any choice but to screw the probe back into place. As far as a gentle way of taking the probe out of the equation... I wouldn't put foil that close to a broil element. Perhaps something else will come to me, but I'm leaning towards a insulating firebrick tube. Cut down an insulating firebrick to a rectangular rod (1" x 1" x 6"?) and then drill a hole down the center.

Hmmm... I wonder how much weight the probe could support?  A cordierite kiln post might work beautifully for this scenario.  Something like this:

http://www.sheffield-pottery.com/TRIANGLE-KILN-SHELF-POST-p/cp5506.htm

The hole at the end wouldn't be a problem. It's just a matter of blocking the IR from hitting the end of the probe.  When you get a chance, could you measure the length of the probe?

[johnamus]

Scott, I like the way you think, the temp probe is 6 inches long.

[scott123]

Thanks, John  

I happen to have two 3" square kiln posts

http://www.anythinginstainedglass.com/fusing/94804.jpg

hanging around so I weighed them- total weight 7 oz. The 3 corner one that I posted a link to should involve less material overall, so maybe that might trim it down to 5 oz.

I then did a little research on oven sensors.  Apparently there's different technologies involved, but, for your sensor, I'm relatively certain that it works pneumatically- the tube contains a gas or a liquid that expands or contracts when heated/cooled.   The reason I looked into this was because I wanted to see what might happen if the weight of the kiln post bent the sensor.  Because of the pneumatics, even a slight bend would most likely irreparably damage it.  If you did bend it, it would be relatively inexpensive to replace.  I don't know, it's up to you.

One thing that did occur to me was that you might be able to take a bent piece of metal (90 deg.), drill a hole through it, attach it to the back wall using the screw for the bracket and use that as a little shelf for the kiln post to sit on/be supported by.

Or, you could say whatever, roll the dice and slip the 5 oz-ish 6" 3 corner post over the probe and see how it goes.  Those probes really aren't that flimsy.

[buceriasdon]

Scott and John, If weight is a concern I would make a cover block from soft insulating brick. Think condom for the probe.    http://www.traditionaloven.com/articles/81/insulating-fire-bricks  
very easy to shape with hand tools.
Don