Rusty cast iron

[GOPHER SLAYER]

In an earlier thread I asked for suggestions on how to remove rust from some cast iron cooking ware. Most suggestions involved filling a large bucket with vinegar and hooking the iron to a battery. I then remembered that years ago I had used muriatic acid to remove rust from tools. I bought two gallons of the acid from Home Depot for seven dollars and gave it a try. While the acid is not as strong as it used to be it still does a good job. Tomorrow I plan on giving it a good scrubbing with one of my wife's pot scrubbers. I am attaching before and after pictures to show the difference. I don't know if they are clean enough to cook with but with a good scrubbing I can't see why not. After all people swim around in the stuff. Of course in a swimming pool it is diluted considerably.

[Skunk1]

Looks nice. What was the cast intended for to use in cooking? Like cooking with cast.

[GOPHER SLAYER]

I haven't decided whether I will use it to cast ingots or clean it up and give it to someone. My wife already has one each these.

[rancher1913]

those make really good ingot molds.

[jeepyj]

Nice job, I also was wondering what that pan was originally used for. Besides casting ingots that is.

[rwadley]

Breadsticks

[Greg S]

There is a ho made solution of molassis and some other items. It is gentle and used by car restore folks on large body panels. It leaves the metal white ready to parkerize.

[Walkingwolf]

I have never worried about rust, first step boil water in the pan for half an hour. Second step oil pan, throw it on a fire. Third step wash pan, oil put up until ready to use. Black oxide is a great cooking surface, seasons well, and stays seasoned.

[54bore]

Self clean oven on the longest setting, thats how i strip and reseason cast iron skillets etc. it takes them down to bare grey metal. I havnt tried a nasty rusty pan tho, the ones i have done were thick built up crud/grease nasty. When the self cleaning oven cycle is finished and the pan allowed to completely cool on its own (thats very important, if you try and speed up the cool down process you risk cracking the cast iron) then i take the piece out and wash it THOROUGHLY with luke warm water and dish soap, use 0000 Steel wool to completely remove any rust, have your oven pre heated to 350 and put piece in for 15 minutes, remove and coat good with Crisco, wipe excess off and put back in the oven to 450 and let it bake the new seasoning on, I usually recoat 2-3 times going through the same method above, gives a good strong durable seasoning and ready to cook in.

[GOPHER SLAYER]

A few minutes ago I was cleaning out the corners of the breadstick iron with a Dremel tool and I saw a tiny speck of brightness in a corner. I got a screw driver and scraped it out, UH-OH, lead or solder. I bought this in a yard sale and it appears someone has used it to cast lead. I guess that decided it's future.

[Ballistics in Scotland]

Quite a bit has been said on this on another thread recently. I would only cook with cast iron I was sure had never been used with lead, and that about rules out yard sales.

Muriatic acid is hydrochloric, and it has been said that it leaves residues which will promote rusting later. I would doubt this, at least if I could find something to boil it in clean water. One or two old gun parts I have haven't gone bad that way. But phosphoric acid is just as good, and has some passivating effect.

[lightman]

Too bad that it has had lead in it. But they do make a nice size ingot thats easy to add to about any casting pot.

[Duckiller]

Does lead really contaminate that much? I have a large pot that I use to smelt in that I will never use to cool thih. But if at some time in the future some cleans it very good would it be ok to cook in? Cast iron is fairly dense and I have never seen lead in any pores. Clean it , heat it to a high temp and then use it to cook in. Would that be ok? What if great grand children didn't know it had been used to smelt lead? If the answer is don't do it ever then we need to destroy our pots when we stop using them to melt ltad.

[54bore]

Does lead really contaminate that much? I have a large pot that I use to smelt in that I will never use to cool thih. But if at some time in the future some cleans it very good would it be ok to cook in? Cast iron is fairly dense and I have never seen lead in any pores. Clean it , heat it to a high temp and then use it to cook in. Would that be ok? What if great grand children didn't know it had been used to smelt lead? If the answer is don't do it ever then we need to destroy our pots when we stop using them to melt ltad.

I've wondered this EXACT same thing? I have bought several really nice old, REALLY OLD Griswold and wagner skillets from Garage sales, second hand stores etc. i have stripped every single one of them down in a self clean oven and completely re seasoned them with 3 Coats. The ones i have gotten i am confident were being cooked in, years and years of baked on grease/gunk. BUT how does one know for sure? I'm gonna take my chances and not worry about it!

[flint45]

We can't worry about everything it will make you nuts my brother won't even touch anything that has lead on it in it or whatever he's a lead a phob!. He had a beautiful old powder horn with scrimshaw and he throu it out because in it was some lead bird shot. I would be willing to bet you can make cast iron safe to use again.

[Tom W.]

Take it to a monument company and let them sandblast it. There usually a nominal charge, and it takes a very short time. Usually the wait is when they have some markers to engrave. When I worked at one we did it on a weekly basis.

[NavyVet1959]

Take it to a monument company and let them sandblast it. There usually a nominal charge, and it takes a very short time. Usually the wait is when they have some markers to engrave. When I worked at one we did it on a weekly basis.

Yeah, I suspect that a series of sandblasting followed by pressure washing a few times would probably work. And there are lead test strips that you could use to give yourself a bit more peace of mind.

[3006guns]

Quite a bit has been said on this on another thread recently. I would only cook with cast iron I was sure had never been used with lead, and that about rules out yard sales.

Muriatic acid is hydrochloric, and it has been said that it leaves residues which will promote rusting later. I would doubt this, at least if I could find something to boil it in clean water. One or two old gun parts I have haven't gone bad that way. But phosphoric acid is just as good, and has some passivating effect.

Muriatic DOES cause after rust......especially on cast iron, for the simple reason that cast iron is porous. The acid gets into the pores and is difficult or almost impossible to remove. You can neutralize it by soaking the part in a baking soda/water solution, dry thoroughly and oil afterwards.

Phosphoric is a lot kinder to steel and iron. Ordinary cola type sodas contain enough phosphoric to derust quite well. Just soak, wait, rinse, dry, oil and done......with no after rust.

An electrolytic setup is probably the safest and best and I've used such a setup for years to derust old antique engine parts. You need a non conducting container (plastic bucket), a piece of sacrificial sheet metal (old flattened coffee can), washing soda (not baking soda), water and a battery charger. The technique is discussed all over the web, just search for "electrolytic rust removal" and pick the simplest setup. At the end of the process, the sacrificial metal will be almost eaten away while your part will have a black "scum" that is easily washed off with water. The only thing I warn people about is to verify the polarity of the battery charger leads. Positive goes to the sacrificial metal and negative goes to your part. Just think "negative....take away rust". The nice part about electrolytic is that you can't overdo it........once the rust is removed the process just stops, so no harm if you forget about it overnight.

[GOPHER SLAYER]

I have been advised that sand blasting ruins collector value on old cast iron cookware. It is true that muriatic acid treated cast iron will rust almost immediately if you don't wash quickly and cover with some form of cooking oil or grease.

[robg]

Bead blasting worked on a very rusty skillet my wife found ,its not as aggressive in its cleaning.helps she works in a custom trike shop.