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).

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 4: Attach charger

Don’t mess this step up – the polarity is important:

Make sure battery charger is OFF:

1) attach the positive (red +) end of the battery charger to the rebar wire

2) attach the negative (black -) end of the battery charger to the alligator clip over the water

3) I remember this by saying to myself “the rust flows off the tool towards the positive side”

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:



What exactly is washing soda, i'm from Argentina and I think that doesn't exist here, so, if you give the components, i'll make it
<p> Washing soda es bicarbonato de sodio en Argentina.</p>
<p>*carbonato </p><p>bicarbonato de sodio = &quot;baking soda&quot;</p><p>carbonato de sodio = &quot;washing soda&quot;</p>
<p>Do you have 20 Mule Team Borax in Argentina? It's the same thing. I use washing soda to make my own laundry detergent. Go to Wikipedia and type in Washing soda and it'll give you a better idea of what it is and some manufacturers. It is also known as soda ash or soda crystals.</p>
<p>It is so not the same thing. Washing soda is sodium carbonate. Borax is sodium tetraborate. The first is Na<sub style="">2</sub>CO<sub style="">3</sub>, the second is Na<sub style="">2</sub>B<sub style="">4</sub>O<sub style="">7.</sub></p>
<p>Thank you for the correction. After reading your comment I did some further research and noticed the differences between the two. But... can't Borax still be used in this process if you can't get washing soda? Just a thought. I realize that Borax doesn't have the same sodium molecules as washing soda but does it have enough to aid the process of removing rust? </p>
<p>The problem is what the sodium is attached to, which in this case is the Borate ion. When you run a current through sodium carbonate, you split water in to hydrogen and oxygen, but the sodium carbonate is largely unaffected. This is because it is more difficult to pry (electrically) the carbon off the oxygen, than it is to pry the hydrogen off the oxygen. With Borax, that's not the case. You'll end up actually changing the borax into something else, most likely sodium hydroxide and boric acid. The sodium hydroxide probably won't have much effect on the process, but the boric acid might. It's commonly used as a flux in welding. I suspect it would end up covering the piece in a difficult-to-remove coating, but that's just a guess.</p>
<p>we studied galvanic cells in chem 2, my understanding is that this can be done with any strong electrolite as the purpose of the electrolite is just to allow the flow of electricity in the solution. </p>
Love great ideas for the handyman..and doesn't cost much..but i was wondering...can a float charger be use..again thanks for putting your Instructions in layman's terms
<p>A few weeks ago I used my battery charger to remove rust from an old rusty block plane. I used a 5 gal bucket, 1 table spoon of Arm &amp; Hammer washing soda per each gallon of water and one 18 inch piece of rebar as a sacrificial piece. The end result was great. I have several old hand saws that havn't been used in several years and are very rusty. I bought 5 pieces of rebar and stripped down some 12-2 housing wire that I had on hand and constructed the same apparatus shown in this blog. I connected the positive to the 5 rebars and the negative to the hand saw, but for some reason it will not work. The charger has 3 indicator lights, one which comes on when charging, one which shows that charging is complete and one which comes on when the battery will nor take a charge. For some reason there is not charging process taking place. The &quot;Check Battery&quot; indicator light is the only thing that comes on. What am I doing wrong?</p>
<p>First you need to verify that your charger will still work to charge a battery (verify that it is not broken ). If it appears to work normally on a regular battery charge, your water may be too pure to cause an ion exchange between the metal bits. You can try adding more arm and hammer to the bucket or try to add some regular table salt ( keeping in mind that Table Salt will give off a small amount of Chlorine gas so work outside with the bucket for safety). For removing rust the best type of battery charger to use is the cheapest NON Computerized chargers with an output of an amp or so. (by the way do not use battery chargers for any other electrolosis than rust removal - most other metal exchanges require more amperage than modern chargers can provide )</p>
<p>I 1st came across this instructable: <a href="http://www.instructables.com/id/Electrolysis-Rust-Removal-DIY-Tutorial/" rel="nofollow"> http://www.instructables.com/id/Electrolysis-Rust...</a> </p><p> And the suggestion box on the side led me to this one. While I dont know if there is a difference in quality in using salt vs baking soda, I liked yours better, being on a larger scale. </p><p>Although I wont be doing this project right away since I'm out of work, and get the the material for free, Some things I would different are:</p><p>- Instead of using rebar, I would use copper ground rods.</p><p>- 1/3 of the way down, and 2/3 of the way down, I would use #8 or #6 solid, bare copper, going from 1 rebar / ground rod to the other, kind of like a cage.</p><p>- At the top where you have them all tied together, I would also a use bigger gauge wire. </p><p>- Lastly, instead of using a 5 gallong bucket, I would a bucket a little taller (to be able to put long items in it.) I used to have that chlorine tablets came in. </p><p>-Optional - if you have 2 12volt car batteries, wire them in series (as seen <a rel="nofollow">here</a>) </p><p> to give yourself 24volts DC</p><p>Just thinking about maximum conductivity, and to have it work faster. </p><p>Cant wait to get back to work to get the materials, so I can built and try it out!</p>
Do not use copper rods. The copper will break down and produce some nasty chemicals.
Thanks for the tip. I was trying to think of maximum electrical conductivity. Also, I was looking for an alternative since I believe someone questioned using rebar since it itself rusts. What would you think about using galvanized ground rods? http://m.homedepot.com/p/ERITECH-5-8-in-x-8-ft-Galvanized-Ground-Rod-815880UPC/202195736/
<p>if your still wondering, I've heard it is a bad idea to use galvanized metals, the zink spilts off and does stuff, I don't think zink on it's own is dangerous, however depending on what you use as a electrolite, instructable author uses washing soda, it may form chemical bonds and produce something toxic. </p>
<p>I have read that you should NEVER use copper, stainless steel, or galvanized in this process due to the mess that copper makes and the noxious substances that come off of the stianless and galvanized.</p>
<p>From my scant bit of research, I've also seen warnings that using copper and/or galvanized steel anodes will result in copper and zinc being electroplated to the item you're attempting to remove rust from.</p>
Question: Could i line the inside of the bucket with half inch net wire or aluminum flashing for better electrode coverage?
<p>you can also remove rust by steeping in water with Molasses added, no electricity needed. :)</p>
<p>I just did this recently and here are two issues I ran into and how I solved them:</p><p>1. Washing Soda: In Northern California it must be banned or something however it is easy to make. Take Baking Soda and spread it out on a cookie sheet or put it into a bowl. Pop it into a 400 degree oven for 40 or so minutes until you have the juiciest pot roast ever seen. If a pot roast has not appeared then you will have Washing Soda. Store in lightproof container.</p><p>2. Battery Charger (IMPORTANT): Automatic battery chargers will NOT work. The electrical flow is not a battery load as it expects and will fault. It will be as if it was broken. I tried two and both behaved the same. Beware of Sears. Online they show a manual charger however it is the SKU of an automatic. This may be another Northern California Space Time issue. Also ordering from Amazon, for all addresses I had it threw an unshippable addresses error. I can buy explosives just fine. I found that eBay has variable power supplies for about the same price as a automobile battery charger and the one I got works great. It is a 0-30V, 0-5A and it costs about $45. There are models with lower voltage/amperage that are in the $20s. Obviously no problem shipping to my address.</p><p>Hope this was helpful.</p>
<p>How funny this came up today! I love old tools and found an old pair of scissors buried in the dirt at a construction site last week, have all this stuff around my shop except the washing powder and will definitely be setting this rig up tonight. Is there any particular brand of washing powder that works best or will any do?</p>
<p>how much washing soda do you use?</p>
<p>Is it possible to use this process to clean steel from flux after gas soldering with brass?</p>
<p>I had a old set of cast iron skillets that were all rusted. A simple soak in white vinegar overnight works well. Couldn't tell you about tool steel, I know vinegar and salt can be used to etch steel using a battery charger. (I etch designs in steel knife blades this way.) Point being, I think this a great method for steels. But for cast iron, just soak in vinegar. Great instructible, by the way!!!</p>
<p>great idea, you can also use water saturated with copper sulfate and your battery charger to etch copper and brass too</p>
<p>Hi,</p><p>I am cleaning up an old British Burmos brass blow torch / lamp made of brass and steel to use as a display piece. The problem is that the steel screws connecting the steel handle to the brass tank are rusted and will not come undone. If I was to place the steel handle submerged in my electrolytic conversion tank still attached to the partly submerged brass tank would there be any adverse effects to each of the two different metal parts?</p><p>Thank you in advance for any answers / advice.</p>
<p>WD-40 Blue torch Penetrating spray.</p>
<p>An impact screwdriver might be the answer there, the simple kind you kit with a hammer, they're actually quite good for corroded screws. </p>
<p>I would need to research this but my gut reaction is to avoid it. Brass is a copper-zinc alloy. I don't know about zinc, but copper does nasty stuff in an electrolysis bath.</p>
<p>If there's any acidity present, zinc is going to have a bad time. A good example of this, is when you make a lemon battery, wherein the 2 leads you insert into the lemon are 1x copper and 1x zinc. After a while, the zinc gets VERY nasty and unusable. The copper, not so much.</p>
Hi,<br>How do you dispose of the electrolytic solution? Is it safe to flush it down the drain or should you better bring it to a collection point for dangerous chemicals?<br>Thanks!
<p>Yes, mciscato, it is ecologically safe to dispose of through your toilet; I'm not sure what it might do to the china surface (I don't think it would harm it, but better safe than sorry) If you think about the contents, there is water, the soda product, and the oxidized material removed from the project; all inert chemicals. the Oxidized material would add iron to your garden spot, or flower beds, which is a good thing I believe.</p>
<p>Thank you brilliant and amazing person!! I now have hope to restore a few much loved items that need a little extra love. I cannot wait to try this and share the results. Thank you again!</p>
<p>When it rusts, can you just use this technique to also clean up the tie wire? Seems it would be worth at least looking into.</p>
<p>How does this process compare, with the very simple process of immersing the object in a tub of 20% molasses and 80% water. Admittedly you may have to leave the object in the tub for a week or two, and it may smell a bit, but it seems to work ....any thoughts ????</p>
<p>In doing both, this is cleaner and yes faster, but the molasses works GREAT too! It depends on what you have, and if this is something you can do. If you have a very thin item, or one with lots of lettering this is better, but I have gotten frozen channel locks and pipe wrenches clean and working with Molasses, but it takes time and wire brushing (a lot). </p>
works great that was after only being in for a few minutes and then wiping with a sponge
<p>if you switch the wires to make the work piece positive and the anode negative you can actually build up the metal, just wondering if this would work on pitted metal for smaller car parts to build them back up</p>
<p>Great Idea, Never thought of Removing Rust, Will give it a try. Thanks </p>
<p>In order for the steel to become brittle, it would have to be in the solution for months or even years. A low voltage will not change the structure at all. I speak after 40 odd years of welding, machining, and HD mechanics. Nice Inst.</p>
<p>I have referred to this instructable many time over the years and I use it on my swamp cooler each spring. I have a large tub made out of PVC pipe and 6mil plastic sheeting. I have a large rebar pattern of a Z for the bottom and one 12 in piece sticking up because the door is 40 in by 40 in. I will do the four doors and pad holders over the course of a couple of days and then brush the stubborn rust spots, reprime and paint and then with new aspen pads I am ready to go. Thank you. </p>
Great idea. But try using TSP ( trisodium phosphate Na3PO4 ) as an electrolyte since Iron(III) Phosphate is incredibly LESS soluble than Iron(III) oxide. [ Ksp = ~1 E -34. &ccedil;ompared to ~ 1 E -20 ]. TSP sold as a commercial wall cleaner in hardware stores.
I used conductive aluminum wire so it wouldn't rust away. Works great.
<p>It seems to me that Lowes (and maybe other Big Boxes) have aluminum in expanded metal available (think screen door guards, lathe panels [4' X8']) that will work for this project. Aluminum makes a perfect &quot;Sacrificial Anode&quot; for hot water heaters in campers, and home water heaters.</p>
<p>can i use NaHco3 please answer me</p>
<p>ALTERNATIVES I've used:</p><p>Baking soda when I couldn't find washing soda at big city stores</p><p>Brass (soft, cheap) wire brushes for cleaning (keep one for before and a cleaner one for after)</p><p>Laptop power supply (more amps is better)</p><p>Small power supplies for small stuff in a plastic coffee can</p><p>Any scrap iron/steel metal instead of rebar - old lawnmower blade is awesome</p><p>Rebar is often on the side of the road near construction sites</p><p>I am lazy...usually my rebar just sticks out of the bucket and I wrap wire around it instead of your fancy holes with tie wires and wire caps</p><p>GREAT Instructable! (other than the red clips on the negative in the photos) I was looking for some reminders...I hadn't done this in about 8 years. Works great for hand tools (even neat old scissors or pliers), all kinds of blades (as you've shown), engine parts. Very easy to re-paint the handles afterwards.</p><p>I keep mine in the garage because of all the rain Houston gets, but I do keep the garage door open since you are making space shuttle fuel (hydrogen and oxygen) and really don't want that blowing up on you. Thanks for this Instructable!</p>
<p>Although not caustic, the solution is nevertheless a skin irritant.</p>
<p>Writing as someone who electroplates, cleaning/prepping steel requires two processes.</p><p>First the item is alkaline cleaned (preferably hot) to remove grease and other debris with or without electrolytic action (although it does enhance the result), then after rinsing being immersed in a weak solution of usually hydrochloric acid. </p><p>It is the latter that removes the oxide/rust - not the alkali. Admittedly a very prolonged immersion will attack the steel.</p>
<p>Here's a video explaining how electrolysis work, I really recommend it!</p><p>https://www.youtube.com/watch?v=URFtlXd0AxA</p>

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