This is a relatively simple, safe and cheap way to remove light or heavy rust from any ferrous object. I used this process to restore an old wood plane that I bought for $1 (it looked totally un-usable because of the rust). As opposed to grinding, heavy wire brushing and acid bath processes, this method removes none of the original steel and is not noisy or caustic.

How this works:

Several other sites do a better job of explaining the chemistry of this - but basically you set up a conductive solution and insert some sacrificial anodes. You hang your rusted tool in the solution and attach it to the negative end of the power supply. You attach the positive end to the anode and turn on the power. The current travels through the solution and in the process flakes off the rust - the flaking/softening occurs because of the reaction at the surface of the good steel that pushes the rust off.

See this site
for more info on the chemistry of it all. (now linked to a waybackmachine archive of the site - modern suggestions for this background are welcome).

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Step 1: Gather supplies

You will need:

This project cost me about $40 because I did not have access to a small battery charger. If you have a charger, then most folks with a decent shop full of crap can do it for almost nothing.

- Clean 5 gallon spackle bucket or other plastic container to meet your size needs
- 5 sections of 18” long 1/2” steel rebar ($5 at Home Depot –
buy in longer sections as needed) (DO NOT USE STAINLESS STEEL)
- 5 feet 12 awg (or so) insulated copper wire in two colors
- 5 yellow wire nuts
- several red wire nuts
- 5 feet pliable tie wire (non insulated) SEE UPDATE on Step 2 - the tie wire rusts out after about a year - you may want to use something more substantial or resistant to rusting.
- Box of washing soda NOT baking soda
- Anti-oxidant goo (IE Noalox – This is not necessary
but helps I think.
- Small battery charger or home made power supply ($20-$50 at AutoZone etc) - Its best if the charger
has a 6v option and an internal "trouble" switch that stops charging if something shorts out.
- Variety pack of alligator clips from RadioShack (unless charger comes with decent ones…)
- Outside outlet or extension cord
- GFCI protected outlet (this is a must in my opinion - working around power and water is stupid unless
you have GFCI protection
- 5 gal water
- misc clamps/small boards
- drill with 1/4 bit
- wire cutting and twisting pliars (linemans tools are best
- wire brush (better if on a grinder or dremel tool)
- anti rust spray or light oil

Step 2: Assemble tank and anodes

NOTE: Do not use stainless steel for the electrodes. As pointed out by a commenter on the intro page (thanks!) "The chrome in the stainless will leach out during the electrolysis and form hexavalent chromium compounds in your electrolyte. These are extremely bad for you." This is true - dont even think about using stainless steel for this project.

Assemble tank and electrodes

1) Space the rebar evenly around the bucket along the sides (running top to bottom). Mark the locations

2) Drill two small holes about 1/2 inch apart 2 down from rim for each rebar

3) Insert a 5" loop of tie wire through the holes around the rebar and out again . Lube the ends of the bar with anti oxidant compound and twist the wire tight and snip off so 1" of the wire is remaining. UPDATE: the tie wire eventually rusts out - mine in less than a year.  Consider using something more resistant to rust - suggestions welcome.  On the other hand, any time you are using electrodes, they are sacrificial - as is the wiring system that contacts the water, etc.

4) Once all rebar is in place, make 4 sections of copper wire with the ends skinned off to connect each rebar wire.

5) Wire nut each rebar to the next with a section of cooper wire (connecting the protruding tire wire (I also used Noalox on these connections). Do not connect the first and last rebar (ie: X---X---X---X---X---)

6) Add 5 tablespoons of washing soda to the bucket and fill within 2 of the rim with clean water (adding extra soda will not help&)

Step 3: Set up hanging clips

Step 2:

1) Find a board (or any non-conductive object) to lay across the top of the bucket.

2) Attach a short lead of copper wire with an alligator clip attached to the water end. (I just stapled the wire to the board)

3) The clip should hang low enough to just enter the water. ( first photo below shows three clips - i was doing three parts at once..)

Step 5: Attach rusted tool

1) clean a small piece of the tool where you will attach the clip - choose a place where it will also hang securely.

2) Attach alligator clip (which is attached to the negative end of the charger) and and hang the tool completely in the water. Its ok if the clip is in the water – it wont hurt it. Wiggle the clip to make sure you have a good connection.

3) Make sure the tool is attached firmly and is not touching the rebar or any part of the setup that is attached to the positive lead.

4) Areas of the tool that do not have a “line of sight” to the rebar will not be cleaned – if you have a complex part you might need to rotate it or add more rebar electrodes.

Step 6: Power it up

1) set the battery charger to a low setting (6v – 1.5 amp works great for me)

2) Turn on the charger.

You should see tiny bubbles start to form all over the tool. As the process progresses, the rust will start to flake off and the water will become muddied with rust and goop and foam depending on how fast the bubbles are forming.

Step 7: Check tool and remove and clean

Depending on the size of the tool, the amount of power used, the amount of rust, and your patience, the process will take from 1 hour to two days. The longer you leave it in the solution, the less work you will have to do to finish the clean up.

The tool will turn black and the rust changes form and flakes off.

If you leave it in long enough, you should be able to wipe the rust off with your finders and find a smooth (but pitted) surface. The nice part about this is that even after only 1/2 hour, the rust is much easier to remove with a wire brush.

NOTE: the tool will not come out of the tank ready to paint. it will still need wire brushing or final polishing with steel wool. the process leaves a gray/black layer of oxidant that you will probably want to remove prior to final rust-proofing or painting.

The photo of the saw below shows three stages: The left side was run for an hour and then brushed. The middle spot was steel brushed for the same amount of time but without the electrolysis (and rust remained) and the right side is the original rust.

Step 8: Samples

Here are a few samples:

The chisel was very rusted – normal rust removal would have required much original steel grinding to remove the deep pits that a wire brush would not have touched. Check out the stamp that was revealed after cleaning.

The entire project was started because I bought this sweet plane that was totally rusted. I only paid a few bucks, but knew that a used non-rusted one was worth quite a chunk of change. After the tank proces it took about an hour of going over it with the light wire brush wheel on the dremel to shine it up – but it would have been impossible without the electrolysis first.

Step 9: Final Rust proofing

If you are not going to paint the tool then it will require immediate rust proofing.

I use this spray T-9 stuff that Highland Hardware sells

– but I think there are some less noxious easier to clean up products out there like Camellia oil

Step 10: FAQ

How big/small of an object can I do?

- My browsing around on the web found people doing anything from small parts in a 1/2 gallon tub to a trailer body in a swimming pool using a large welder for the power.

Does the solution "wear out"?

- No - it just gets nasty

How much power should I use?

- As little as possible to still get the job done. I think you will get better results with low power and two days of processing than high power and getting it done in an hour. The larger the object (surface area) the more power required to do it in a given amount of time. My charger is 1.5 amp 6 volt and works great for hand tools. the small stuff takes a few hours. The larger complex plane took a day and a half before i was happy with the amount of removal.

Is this dangerous?

- Only if you don’t have any common sense and don’t use a GFCI protected power source.

- Yes if you do it inside - the bubbles forming are evidently hydrogen which is flammable. Outside it does not cause any problems.

- The low voltage is pretty safe - especially if your charger has an automatic cut off "trouble" switch.

Are there any drawbacks to this system?

- Some people say that depending on the power and time involved, the steel can become brittle due to a temporary change in structure. This is cured by "baking" the tool for a few hours at 350 in the oven or letting it sit around for a few months before any hard use. see the links below for more info. I have not found this to be a problem.

These guys deserve the credit for teaching me how to do this and provide way more info on this system:
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lord.bagel1 month ago

If someone would be so kind as to help me out here... I followed all the steps, connected the black negative clip from the stanley 2-amp (BC209) battery Charger (for 6 Volt and 12 Volt Batteries) to my item and the positive red clip to a sheet of steel. As soon as I plug in the charger, the "reverse polarity" warning light turns on. I'm only reading about 0.3 volts between the item and the steel anode... nothing's happening.

You need a Manual charger, not an automatic

That is your issue. Your charger has a circuit to detect a valid battery and doesn't apply current unless it sees what it wants. Harbor Freight chargers do this too. You need to find an older or non-automatic charger, or a fair sized 12VDC wall wort transformer. I've used an old laptop charger for this purpose before and have "modified" HF chargers to be non-automatic for use as a 20A 12V power supply.

Go to Cast Iron Cooking facebook page, or google Electrolysis tank; it will help answer your questions.

lord.bagel1 month ago

If someone would be so kind as to help me out here... I followed all the steps, connected the black negative clip from the stanley 2-amp (BC209) battery Charger (for 6 Volt and 12 Volt Batteries) to my item and the positive red clip to a sheet of steel. As soon as I plug in the charger, the "reverse polarity" warning light turns on. I'm only reading about 0.3 volts between the item and the steel anode... nothing's happening.

rseufzer5 months ago
I used conductive aluminum wire so it wouldn't rust away. Works great.
TheReusery5 months ago
I found the best thing to use as an electrode instead of rebar is expanded metal that is cut and bent to form a perfect circumference inside the bucket and attach with bolts that can also be used as your conductors . This eliminates "line of site" issues .
sochart1 year ago
I'd like to setup an electrolysis station in my garage. Can I add some antifreeze in the system for the next cold months ?
pet14152 years ago
I need the name for my science fair please. Great article
Electrolytic Rust Removal is the process.
Washing Soda is also known as ("aka") sodium Carbonate (not bicarbonate, that is baking soda, won't work)
Anode is the POSITIVE (red clip) power type, it goes to the sacrificial part.
Cathode is the NEGATIVE (black clip) or GROUND power type, it goes to the part to be cleaned. The electricity flows from the POSITIVE to the NEGATIVE, so it takes the iron with it and cleans off the junk by the new iron trying to reach the old iron.

Hope these terms help....
ToolNut and everybody else on this site.
I'm new to the site and retirement. This tutorial is just what I need to salvage stuff I've accumulated over the years. I know I'm anal and maybe my concern has been addressed in an earlier post, and if it has I hope the administer will delete this comment. But if anybody's concerned about safety, NEVER NEVER use the wrong colored clips for connections. RED is always positive and an uninformed person with the best intentions could mix things up and trash a good charger. I'm sorry, what I was referring to were the pictures in Steps 2,5&6. Please correct me if I'm wrong and I appolagize if I am.. But isn't there a red clip connected to the blade? and shouldn't it be a negative connection (black) I hope I didn't offend anyone.
Be Safe
ToolNut (author)  allniterunner2 years ago
It is a red clamp, but not related to polarity. I had to use a spring clamp to hold the wire onto the tool, and the clamp I happened to have was red. I can see how that would be confusing. If I ever re-do the pictures, I'll buy black clamps for the tool. the wiring is negative to the rusty tool, positive to the rebar/anodes. Step 4 outlines this.

No offense - and good clarification! I will make a note on the picture.
My most humble apologies. Considering all the great contributions you've made to Instructables I had no right to question your method and should have understood better what you meant by initial set-up. The operation worked better than I could've asked for and did a great job on my parts. I'm sorry that my initial post had to be one as a snob. You did great portraying the concept of how it should be set-up, and I failed to be more comprehensive in my reading. As I sit at your bench of wisdom I hope to absorb many more ideas and tricks of the trade that I missed the first time around.
Thank you for not torching me

I don't think you need to apologize, and he can correct me if I'm wrong, but I think ToolNut didn't expect an apology either. The fact that you might not have commented if you had been "more comprehensive" in your reading actually highlights one of the risks of Instructables: a picture is worth a thousand words. That red-handled spring clamp DOES look an awful lot like the positive clamp of a battery charger, and you may have saved someone from using their favorite old tool as a sacrificial anode to brighten up some cheap rebar!

Instructables has no shortage of "concern trolls" (NEVER do ANYTHING with electricity EVER!!!!1!), but the good authors seem to welcome comments that point to photos or text that might be misinterpreted by reasonably intelligent people.



(just kidding!!! thanks for the laugh!)
ToolNut (author)  ToolNut2 years ago
Also, note that I state on the photo that uses this clamp that its a hokey set up as my first run, and the alligator clips were a good upgrade.
tbird23402 years ago
Great article.. So what is the consensus for the metal to use if not the rebar?

Also, I don't have any of that tire wire and not sure HD or Lowes even sells that.. Can you just use electrical wire for that?

Anyone know what store(s) have washing soda readily available?

I have this charger here: (12V 1.25A).. Will it work OK?

I plan on dunking my rotor(s) and hopefully my calipers as well..
Wal-Mart. Go to the cleaning products - laundry detergent, dish soap.

I found Washing Soda at Fred Meyer and assume it can be had at other Kroger stores like QFC, but sodium carbonate is also sold as a PH up product for pools and spas and as a water softener. I found some at Home Depot, but had to ask where their very well hidden pool chemicals were.

This is my first post here and I don't wish to offend, but this isn't an instructable for the perfect electrolysis tank, just ToolNut's design of "an" electrolysis tank. That's not meant to criticize, but to point out that every single thing can be replaced with something else(except water and electricity) that you probably already have and that might actually work better. Don't get hung up on the details.

Ideally you'd want the surface area of your anode to be equal to or greater than that of the cathode(the part you're trying to clean).

The battery tender should work just fine, but might switch to "float" as the part gets cleaner.
It's been a while but SCUBA shops used to have all plastic wire ties, to prevent various attached items from disappearing due to corrosion.
Good Luck
mr fat1 year ago
jew991 year ago
hi it's great work even many years past. THANK
Ian.Harrold3 years ago
So why did you not connect the first to the last rebar? Electrically it is already connected, but I would think you would want provide even electron flow by tieing them together.
I am intrigued and wondering the same thing?? Why not ToolNut?
because it could short circuit the (anode? or cathode?) the negative terminal by completing the circuit therefore welding everything to itself. Bad idea.
Corey11: So you're saying that connecting all the anodes in a big cirle could short out the entire thing - but how is that different from connecting all the anodes in a chain-like way?
ToolNut (author)  corey112 years ago
Really?? I cant figure that one out - it would basically be a loop on the end of a negative circuit -its not touching back to the positive - just the negatives all connecting together... Basically a big version of the little loop on the negative terminal of your car battery as far as I can tell... Or am I missing something?
ToolNut (author)  Ian.Harrold2 years ago
Hey Ian -Sorry for the massive delay in responding (kids!) - I dont think it was a super well thought out aspect of the design. I don't I agree with corey11 (see my response below) that it would be catastrophic - but any system you design you need to be comfortable with the safety etc etc. I didnt worry about even electron flow because I dont think its enough current to run into resistance issues by having to go further around the bucket, and honestly it was one less connection I had to wire together! Though it does mean that if you have a bad connection at the rebar (or eventual rusting out of wire) then the whole line goes out rather than just half.
HasBeen1 year ago
If you are getting flash rust on unpainted metal after cleaning with electroysis, you mite try using Fast Etch from Eastwood. It leaves a zink posphate coating to help prevent future rust.
HasBeen1 year ago
Nylon zip ties will hold your rebar securely, but you will still need copper wire around the rebar for the electrical connection. Also bend the copper wire so wire nuts point with open side down so they won't fill with any splashed solution and rust out quickly.
cstaton11 year ago
Hello, I'm currently doing this in the back yard, loosely based on your instructable. What I'm noticing is, with tools with uneven rust coverage, that the areas with the least rust seem to attract most of the electrolysis, leaving the most heavily rusted areas untouched. Have you noticed this? Is there a way to counteract it?
tercielo1 year ago
can I use ordinary laundry detergent?
netskink1 year ago
I was thinking of using galvanized steel chain to suspend a steel rim I wish to remove rust from. Any idea if this will be a problem.
This is to help a lot of you understand how to make this work better. Please don't get offended by what I say I'm not going into my back ground of what I do but I do know what I’m talking about.

1. stainless steel does not conduct amps well don't use it.
2. Copper for your anode is better used and a copper pipe flatting ¾ of it with a hammer
3. the further your anode is away from your work peace is bad it takes more amps and time to work on cleaning.
4. Power 1 to 12 volts they don't matter at all amps is what matters 10 amps works the best no closer than 4 inches from what you are cleaning the farther your anode is from what you are cleaning the more amps it takes to do the job.
5. Cleaning soap phosphates use TSP you will find it in a store that sales paint it is a mild soap use
for cleaning walls in the house to paint. It will not harm you. Plus add two cups of white vinegar to 4 gallons of water in your 5 gallon buck of water mix with soap it will help to conduct the amps better. O and what I mean that TSP won't harm you I mean your hands please people don't drink it is a small joke:)

and one more thing please people stop telling people that stainless steel is toxic if they use it because its not it just wont carrier the amps. The only way to make it toxic is to weld with it over a long time or by passing volts throw it at high amps in a acid bath and I mean amps 150 amps and up.

Thank you for your time hope this helps
Stainless is a conductor, just not at the top of the list. 316 has high corrosion Resistance and for the short length and low watts (volts x amps) it's fine. Mechanically it would be feasible if the electrode is .250 or larger. The reason not to use any Stainless IS toxicity.
When S.S. undergoes electrolysis hexavalent chromium (remember Erin Brockovich?) an industrial byproduct and toxin is produced due to chrome in the SS being released into the electrolyte. The result is a disposal problem. If you doubt any of this, research HHO fuel cells and you will see Stainless is used as anode and cathode to create Browns Gas A.K.A. HHO(hydrogen, hydrogen, oxygen). Having a disposal problem is not on my list of must haves, so I'm forced to look at titanium which is very expensive, and only moderately conductive.
ToolNut (author)  maverickcanakay2 years ago
maverickcanakay - good stuff! I appreciate the input, and I may figure out how to incorp some of this advice into the actual instructable with some updates. I'm curious about your background in this, but fine if you'd rather not share.

Re the stainless steel advice - there is simply too much other advice out there warning of the potential hazards of this, so I am going to maintain my statement that stainless should not be used. for example, here is one of the original electrolytic rust removal sites that was inspiration for this instructable:

So anyway, I'm going to stick to err on the side of caution on this one and continue to caution against stainless, but am interested if there is something definitive on this. Lastly, I don't see a real benefit to stainless, its more expensive, and we are talking about a disposable anode by definition, no matter what kind of conductive material it is...
I have done a ton of this rust removal process. I mean well over a ton. I completely restored a 14x40 Davis metal lathe and a Index vertical end mill. Both were completely rusted solid. They are now ~100% operational. I used almost exactly the process listed above with only minor differences.
1. I only used washing soda in a 1tbsp /gal ratio. My largest tank was 7ft W X 3ft L X 3ft D. This was for the lathe bed and the Mill body.
2. My anodes are always steel plate. Plain old 1/8" mild steel. Pieces about 10inx 12 in. In the large tank I had 8 of them. In a 35gal plastic garbage can where I did most everything I used 2. I drilled a hole and bolted bailing wire (now called tie wire) to them and hung them in the bath.
3. I clean my pieces using a plastic bristle brush and some orange gojo degreasing hand cleaning stuff. Just get the grease off your part so it will conduct. This process has removed everything from unseen grease and dirt & paint, but especially rust!
4. Leave overnight.
5. remove the anodes and simply wire brush the crud off and set them aside to be used again. The anodes will corrode completely away eventually. I think it kinda looks cool the pitting and corrosion that occurs on the anode. the way I see it, the more surface area of the anode the more electrons can flow onto it and the more rust it removes.
Sorry I don't have pics of the tank ( I may somewhere) but I do have before and after pics of the machines, however in the after they are completely repainted. I've done parts hanging half in the bath then rotated over after the first part is done. Screws bolts and nuts are easy when you simply cut a long piece of wire then tie them all together with a couple wraps around them and space them about 1" apart. the results are nothing short of amazing. There is no damage to the original part.
Warning!! Get the polarity right! If not you will corrode whatever you are cleaning into something unusable really quickly.
ToolNut (author)  SvenPetersen2 years ago
Nice man - that is some serious restoration dedication. You are inspiring me to scale up my ideas here. What did you use for a power source? Batt charger? If you find pics of the tanks, I would love to see.
ToolNut (author)  maverickcanakay2 years ago
one more thing re copper - and I dont know squat about this statement, but am curious about this guy's take on it:

"It is important that any copper connected to the anode does not touch the solution. If it does, copper will oxidize to cupric ion, Cu++. The connector will be destroyed. Most of the copper ions formed should precipitate as copper carbonate or copper hydroxide, but if any of this dissolved copper reaches the cathode it will be reduced to copper metal on the iron object. Its presence will promote rapid re-rusting."
PitStoP2 years ago
Can this process be used to remove rust from chrome plated metal? I want to restore a drum set and most of the chrome has rust. Any info and advice on doing this will be appreciated. Thanks
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