# Cast Iron Electrolysis Rust Removal



## Dutch (Dec 31, 2007)

The following rust removal setup work great for those pots that are really rusted up. I use this setup a couple of times a year when friends bring me their negelected cast iron and when I find a D.O at a yard sale or a thrift shop. This info is from a site that I sometimes visit, especially when I think I have found a really old piece of cast iron-mostly though it turns out the the piece just "looks" really old. 
	

	
	
		
		



		
			







*Rust Reduction Electrolysis Setup*

Rust reduction via electrolysis is almost harder to say than it is to set up. While it appears to be a way to remove rust, it is actually a rust reduction method whereby hard red rust (ferrous oxide) is reduced to soft black rust (ferric oxide). There is not much to setting up an electrolysis bath and this simple process will produce spectacular results on rustiest, crustiest, carbon-caked cast iron utensils you can find. There are only four components necessary for the entire setup...

1. A Battery Charger.
While any charger will work, a 12-volt charger capable of 35 to 40 amps is ideal. A 6-volt charger or a trickle charger will work, but will be extremely slow.

2. A non-conductive tu b or container.
This is to hold the solution and must be non-metallic. A five gallon bucket, an old cooler, a Rubber-Maid tub, a plastic 55 gallon barrel, anything that will hold the rusty utensil will work.

3. A non-conductive rack to hold the cast iron away from the anode. A plastic parts bin or dish rack will work nicely. 

4. A supply of Sodium Carbonate. This is to create an electrolyte solution that is capable of carrying the current created by the battery charger. Two readily available sources are "PH+" (a swimming pool additive available at Wal-Mart or any pool supply house), or "ARM and HAMMER WASHING SODA" (Not Baking SODA). This is a laundry detergent available at most grocery stores. Itâ€[emoji]8482[/emoji]s in a big yellow box just like the baking soda and is found with the Tide, Oxi-Clean, Clorox, etc... Use 1 Tablespoon per gallon of water in your container. This does not have to be an exact measurement. Another measurement is two handfuls per every five gallons. Make sure the soda is well dissolved in the water.

5. Two chunks of metal. The one you want to clean and another you donâ€[emoji]8482[/emoji]t. Any cast iron cooking utensil can be cleaned. Cooked on carbon, rusty, and the worse it is the better it will look. The other piece is technically called the anode. It is what we will be electroplating with the rust from our good piece. Just about anything metallic can be used for your anode. Re-bar, angle iron, coffee cans, shovels, cultivator sweeps, whatever you have handy. The ultimate is stainless steel as it will be less affected by the process, but donâ€[emoji]8482[/emoji]t use your wifeâ€[emoji]8482[/emoji]s stainless steel potato masher without permission (voice of experience here). The larger the surface area of the anode and the more it surrounds the article to be cleaned the better. Try a coffee can with the lid flipped up and the side split and spread out. It makes an easy one to start with. Now comes the fun part.

You must rig your setup in such a way so as to suspend the article to be cleaned next to but not touching the anode. Old dishwasher racks, bolts, c-clamps, bar clamps, duct tape, baling wire, let your imagination run wild. The desired result will have the anode secured and the part to be cleaned next to, above, or below it but again not touching. If something doesnâ€[emoji]8482[/emoji]t look right, stick your hand in the water and straighten it out. The solution is harmless. Make sure it is secure enough so that a bump wonâ€[emoji]8482[/emoji]t tip something over. Now for the critical part... the red (positive) battery clamp must be attached to the anode (scrap piece), and the black (negative) clamp MUST be attached to the part to be cleaned!!!

Now hook your red clamp to your scrap iron and the black clamp to your griddle. Make sure you have a good connection. Use copper wire and more clamps if you need to completely submerge your piece. If it will only partially fit in the tub, you can turn it over and do it in two or more sessions. There will be no lap marks. Try not to allow the red clamp to come into contact with the solution as it will be attacked by the process. The other (black lead) may come in contact with the solution but will have to be cleaned frequently.

Now turn the charger on! If equipped the charger amp gauge will jump slightly. Bubbles should immediately start coming from around the iron pan. If not, check your connections. Make sure you have good metal to metal contact at all points. Let it run for an hour or so and check your results. Always turn off the charger before playing in the solution. If you donâ€[emoji]8482[/emoji]t it will let you know. You will see a black coating on the cleaned part. This can be removed by an air compressor or by washing. Bare metal will lie underneath. The bubbling action is what cleans the cooked on carbon off. Sometimes it needs a little more time to clean. But this method is self-correcting in that you cannot over cook it. The clean metal will stay just the way it is and the crud will be removed. Let it cook for 6 or 8 hours and come back to it. The carbon will fall off. Polish it a bit with your favorite method if you want, but it is not necessary. Season it soon as it is extremely susceptible to rusting at this point. Now go show it off to your spouse.

_JUST A COUPLE WORDS OF CAUTION. _The bubbles coming from the process are pure hydrogen. It is extremely flammable. Do not set it up by an open pilot light, and make sure you have some ventilation. Failure to do so will probably wind you up on the Darwin List.

The solution will become rather â€˜horribleâ€[emoji]8482[/emoji] looking in just a short time. But the solution will last forever. Only add water for whatever evaporates, as the sodium carbonate will stay suspended. When you canâ€[emoji]8482[/emoji]t take the look anymore, simply dump it out in the yard. It is iron enriched laundry water at this point.

Be ingenious with your setup. Try whatever seems right. Hook two anodes together with a copper wire and do two sides at once. Find something plastic to set your part in. Resurrect that old cooler with no lid and set it up. Hit the brakes hard and have your spouse grab that great looking piece of stainless in the barrow pit. Start buying those really rusty pieces of iron because you love the challenge. Try it once and youâ€[emoji]8482[/emoji]ll never go back. And all that old iron will love you for it...


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## Dutch (Dec 31, 2007)

Since I had more than the 5 allowed pics to post, I split the post.

Here are a couple of pics of the cast iron fry pan that is used in the above post. They are a "Before" and "After" pics.


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## cajun_1 (Dec 31, 2007)

Thanks Dutch  ..  I also visit that site  ...  I was slow this year, my setup if now frozen in my garage


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## short one (Dec 31, 2007)

Dutch, thank you for the very informative post  on cleaning rusty cast iron. Will come in very handy and I will start looking for more cast iron treasures.


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## walking dude (Dec 31, 2007)

nice dutch REAL nice..........

question.........what did you use as a anode?

what is that refridge rack i see in one of the pics?

deff. bookmarking THIS post


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## vulcan75001 (Dec 31, 2007)

Dutch Sir...
May I make a suggestion that you make your post a sticky....so that valuable info doesn't get lost in the cracks somewhere...great info.. thanks


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## garyt (Dec 31, 2007)

This is great, I work with chrome and phosphate plating but I never new this was possible, now If I can ever season a pan and not have my wife or girls not wash it in soap I am in business, By the way as I am typing this I am making my first batch of Wicked beans. Thanks for 2 great Ideas in one day.

And tomorrow is the first day of a new year, who knows what I will learn at this great site!!!!!!


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## richtee (Dec 31, 2007)

"We" do, collectively...LOL! And hope to learn from you, too  :{)

Happy New Year!


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## peculiarmike (Dec 31, 2007)

Dutch is dead on with this method. I play with antique hit & miss and Maytag (as in Maytag washer) engines. I used this method to clean a cast iron gas tank from a 1936 Maytag engine that had sat unused since 1948. The two cycle gas/oil mixture evaporated leaving a heavy hard residue coating the inside of the tank.
After two days cooking the process cleaned the tank to bare cast iron.
I used a large plastic trash can with three 1' long pieces of 1/2" rebar tied together with copper wire as anodes and a Craftsman heavy duty battery charger. Suspended the gas tank in the cleaner on a short length of chain. Hooked the charger leads to the anodes and the chain.
Here is a link -

http://www.stovebolt.com/techtips/ru..._derusting.htm

I'm playing with a 1950 5 window Chevy pickup also. 
Between playing with my toys I smoke things.


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## Dutch (Dec 31, 2007)

W.D. I used a sheet of 1/2 inch expanded steel sheeting cut to fit the bottom of the plastic tub, to that I used a 1/2 inch threaded steel rod connected to the expanded steel sheet. A large fender washer and nut was fastend to the rod, the rod then inserted into a corner of the sheeting and another fender washer and nut threaded onto the rod and every thing cinched up tight.  The refridgerator rack is used as the bast of anode and it was attched to a steel rod, pretty much like my set up is.


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## Dutch (Dec 31, 2007)

Richard, I thought that folks would want ready access to this info, so I made it a "sticky post" right off the bat.


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## cowgirl (Dec 31, 2007)

Good thread Dutch, thanks for the info!


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## vulcan75001 (Dec 31, 2007)

Thanks Dutch..


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## cman95 (Dec 31, 2007)

Very good info. Thanks Dutch.


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## zapper (Jan 1, 2008)

http://antique-engines.com/stainless...electrodes.htm


I don't know how much before it gets bad, but thought I would share.



My old man claimed to be a junkyard mechanic and collected gas engines. Oliver, Hercs, Areos, Maytags, Mccormicks, International tractors and old cars, Stutz, Studebaker, Maxwells, Dodges. I wish I knew a tenth of what he did.


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## ncdodave (Mar 22, 2008)

The IDOS region 2 Dutch oven gathering is setting up an electrylisis tank for everyone to look at and watch and use. The Gathering is being held in the town of Three Rivers, Ca at the three rivers hide away campground


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## badfrog (Dec 13, 2009)

Great info...I cant wait to try this out. I have two skillets (griswalds) I bought at a yard sale that I was planning to clean in my bead blast cabinet, but this looks like a much better method.
Thanks Dutch!


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## peavley (Oct 20, 2010)

Hey yall, I have a question about this set up.  I have been trying to do this now for the past few weekends, I have a plastic 55 gal barrel, re bar for the anode...seven pieces actually and it is all linked together with copper wire.  I submerged my cast iron in barrel the first time and nothing happened, but I figured it was my newer "SMART" charger giving me trouble because it kept giving me a fault reading.  So I borrowed my dads older battery charger and hooked it up and still nothing happened.  So then I tried to check the charger so I hooked it up to my truck battery and plugged her in...and nothing happened, the needle did not move or anything.  I guess what I am wondering is that a sufficient way to check the battery charger?  Shouldn't it have done something when hooked up to my truck battery?  Before I give up on this I am wondering if my dads battery charger may just be bad. 

Any thought would be appreciated.


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## dale5351 (Oct 20, 2010)

Another technique I have been told works well (but have not done myself) is to treat it with ammonia.  A friend says that he has done it multiple times with cruddy cast iron picked up at thrift shops, garage sales, etc.

From this link on the web:

I tried ammonia to clean two small cast iron pans.  It seems this method works quite well for people who have lots of time to wait and plenty of ammonia.  The first pan was VERY rusted.  It looked like something had been left in the bottom and rust had formed over top of that and all up the sides.  I wrapped the pan in a rag and put it down in a plastic grocery bag.  Then I poured ammonia all over it, wrapped it up in the bag, and put that down in another plastic bag to keep the odor down.  All in all, (with lots of peeking and a little scrubbing along the way) I left the pan there for two weeks.  Most of the amazing stuff happened the first 3 or 4 days.  The clumps of rust were gooey and loose after just a day or so.  After the first week, I don't think it really made that much more progress, and I ended up hand sanding it the last little bit.


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## eman (Oct 20, 2010)

There are a few ways to check the charger, easiest is a dc volt meter or you can get a 12 v piece of equipment ( air pump ,light, motor ,etc ) and check it that way.


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## rugsrme (Mar 15, 2011)

Has anyone tried this with the "pre-seasoned" cast iron?  I got a new pan and the coating is already starting to show bare metal in a few spots after a couple uses and cleaning (hot water and a dish rag, no soap or abrasives).
I'm going to try it, just wondering if anyone has yet.
My goal is to get all the pre-season stuff off and have bare metal.
I'll post my results.
Thanks,
Q

[edit] Yes, it's working, I can see spots of bare metal forming all over where the bubbles are forming.:yahoo:


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## fpnmf (Mar 15, 2011)

Peavley sez<<<<, but I figured it was my newer "SMART" charger giving me trouble because it kept giving me a fault reading.  >>>

 Most of the modern smart chargers will not work if there is not a minimun amount of voltage present. If a battery  is dead ya have to charge it off off a good battery for awile to get enough juice for the smart charger to work.

  Craig


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## i is a moose (Mar 16, 2011)

What I've had success with in the brand-new cast iron department is to immediately chuck it into a sinkful of hot, soapy water (yes, it seems counter-intuitive). Scrub it down really well with a gentle abraisive, like the green side of a fake sponge, rinse it, dry it,  smear on a little crisco and put it in my oven on the highest setting until all the oil smokes off, then smear on more, and repeat the last part at least three times, then let them cool on the stovetop for about 12 hours so things can "set" and you'll have a bulletproof season, just keep it clean, and do a gentle 1-coat reseason after every use.

Good luck!
 


Rugsrme said:


> Has anyone tried this with the "pre-seasoned" cast iron? I got a new pan and the coating is already starting to show bare metal in a few spots after a couple uses and cleaning (hot water and a dish rag, no soap or abrasives).
> I'm going to try it, just wondering if anyone has yet.
> My goal is to get all the pre-season stuff off and have bare metal.
> I'll post my results.
> ...


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## mechanicbutcher (Jun 20, 2012)

to check a battery charger just strike the clamps together. If it scares ya its workin.   and thanks dutch thats awsome. I'm goin to get me some of that laundry soap just for kicks.


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## mechanicbutcher (Jun 20, 2012)

oh yeah i use kosher salt and a paper towel to scrub any residue in the cast.


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## oldguysrule (Jul 4, 2012)

Would this work on steel?  I have some plow disc that I use to make woks and would like a wa to remove rust without chemicals.


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## oldguysrule (Jul 7, 2012)

I have a "Witchs Brew" pot.  It is very large.  I am only interested in cleaning the inside.  If I set it on an old tire keeping it up off of the ground and I out the negative connection to the pot itself and connect the positive connection to the donate object would it clean the inside?


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## linguica (Feb 17, 2013)

Better Living Through Chemistry.......I think I've heard that somewhere before........Timothy Leary.


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## smokinclt (Apr 2, 2013)

Dutch,

Just wanted to say thank you for the post. I will be doing this in the next few days and I can  get 100+ dollar DO's for about 15 to 20. Amazing write up and tips. 

Thank you!! 
	

	
	
		
		



		
		
	


	





Doug


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## dirtsailor2003 (Apr 5, 2013)

Weather permitting I will be doing this to the rusty lid bands for the CasaQ. I've had everything ready to go, but the weather hasn't worked with my schedule!


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## kathrynn (Apr 5, 2013)

Dirt....vinegar...plain white vinegar will work for that too.

Just Saying!

Kat


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## dirtsailor2003 (Apr 5, 2013)

KathrynN said:


> Dirt....vinegar...plain white vinegar will work for that too.
> 
> Just Saying!
> 
> Kat


But that's not as fun as playing with electricity, water and potentially flammable gasses!! I've tried the vinegar method before and I don't think it'd have enough ooohmmmppphhh to get 44 years of coastal rust off!


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