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I posed the question recently about how to remove rust from this toolbox full of neglected tools. I got lots of suggestions in the comments recommending different methods. I’ve decided to try out as many of them as possible. First up: soda.

Owing to its phosphoric acid content, Coca Cola has a pretty good reputation as a remover of iron oxide. I chose a bottle of Mexican Pepsi, since it’s made with cane sugar and I’m pretty sure high fructose corn syrup is bad for tools (kidding).

I placed this lovely wrench in a small container, poured in the Pepsi, and let it sit for four days. When I pulled it out I was half-expecting a gleaming, new tool to emerge. Instead, it had removed some of the surface rust, but none of the more serious crud.

I’ve decided to put it back in with a fresh bottle of soda (this time a Mexican Coke) for another week, and then see if there’s much change. As usual, if anyone has advice on this technique, please let us know about it in the comments.

John Edgar Park

John Edgar Park

John Edgar Park likes to make things and tell people about it. He works in CG animation at DisneyToon Studios and writes for Make, Boing Boing, and other places online and in print. You can find him at jpixl.net and twitter @johnedgarpark — if you like that sort of thing.


  • http://www.facebook.com/yummyhits Martin Hardy

    What would happen when we drink same soda

    • http://pulse.yahoo.com/_KDNAQJJAIOCDSO5IW7KZ3IFSFM Dustin

      It will clean your teeth?

      • http://www.facebook.com/profile.php?id=820893538 Adric Menning

        why, do you have rust stains on them?

    • http://www.facebook.com/jerry.willman Jerry Willman

      The soda would be fortified w/ iron. If cereals can have actual metal in them. Why not soda. lol

  • http://www.facebook.com/people/Thomas-Baird/1800834410 Thomas Baird

    You could just use a wire brush and wd-40 for about 3 minutes instead? lol

  • http://pulse.yahoo.com/_ZQ3NMW4U6BIWMBSPZZO6P2KNTI Steven Sprague

    I know this comment is not about using Coke to eat rust, but if getting rid of rust without using harsh chemicals is your end result then – Evapo-Rust!

    I have read lots about it for hand plane restoration. I have been dying to try the stuff, it is supposed to be the bomb for rust removal.

    http://www.evaporust.com/

    I have scene potatoes are supposed to work really well:

    • Anonymous

      I have it and it works very well. It’s around $20 a gallon, which would turn some people off, but I don’t think it’s priced too high.

  • http://www.facebook.com/peejaybee Phillip J. Birmingham

    Back when I was a kid, we used to use oxalic acid to remove the rust from the beer cans I collected.

    • http://pulse.yahoo.com/_PZYK5NC4DSEK2FFYXGZ3MOSBSY FlatTop

      +1 on the oxalic acid; I have some scabby motorcycle parts soaking in it at home right now. An overnight soak is usually enough, just brush off the resulting green crud with a brass brush, rinse in baking soda/water solution, and wash with clean water.
      It’s sometimes sold as wood bleach or wood brightener. I ended up getting some at West Marine.
      BTW, that wrench will never look like new because the chrome finish is gone. And before soaking it anything, be it Coke, molasses, oxalic acid, or whatever, knock the loose, flaky bits off with a steel brush so the chemicals can get to the rust at the surface.

  • Anonymous

    12v battery charger and

  • Anonymous

    Use a battery charger and some washing soda….check out the process at about 2:40 into this video on restoring an old hand plane.

  • http://pulse.yahoo.com/_FLVU66R7HFC4EC6JNFO3URGHUE Gabe Shackle

    Electrolysis is a lot more effective and more fun! It also will not damage the actual metal of the tool, helping to keep it’s patina.

    • http://pulse.yahoo.com/_6H27GAF7PXG4DJSF6MEMVB2OVA JamesB

      I’ve done electrolysis rust removal on car parts and it works well: the rust just sheets off. Clamp an automotive battery charger lead on the part, clamp the other lead on a stainless pot (I used a piece of mild steel, but you have to scrub it fairly regularly), then put both pieces in a tub of water with washing soda. It makes hydrogen gas, which can supposedly accumulate to the point of being a hazard, but I tried to light it and no burnee. Also, you are creating something of a directional electrical field in the water; so it helps to occasionally rotate the piece relative to the collector plate, or use more than one plate.

      • http://pulse.yahoo.com/_LQ4K6VN66XDTBABZ5THRPWVUYU Stephen

        No, the field is completely screened by the electrolyte. There is no electric field beyond (at the very most) a few nanometers from the electrode. Rotating either electrode does nothing for a surface process like rust reduction — if you are plating and have generated a concentration gradient, then you might see a benefit from stirring, but rotating the electrode every once in a while will have almost zero effect.

        • http://pulse.yahoo.com/_6H27GAF7PXG4DJSF6MEMVB2OVA JamesB

          Have you ever actually removed rust from old auto parts using this technique? The rust mostly comes off the side facing the plate.

    • http://www.facebook.com/profile.php?id=820893538 Adric Menning

      Indeed my dad’s shop has restored many a ugly rusty tool that way. plastic bucket, bundle of rebar, a few teaspoons of washing soda and a battery charger.

      avoid doing it with stainless steel as the container or positive electrode. , the water can have chromates in it and would require evaporation and hazardous material handling/ disposal.

      Pretty neat to take a saw thats totally red and covered in scale, and in a day or two you can wipe off the rust, and read the stamped info.

      post electrolysis de-rusting you should bake it dry, and then apply protectant.

      Quelab.net Albuquerque’s most active Hackerspace!

  • http://twitter.com/Danorz Cube

    i hear a big bucket of reaaaally strong tea works really well because of the tannic acid, but who knows if it works better than cola, it does have a nice “tea solves everything” thing to it though

  • http://www.facebook.com/ross.hershberger Ross Hershberger

    What about temperature? I assume this was left at room temp. A warmer place might speed the reaction. Most of the chemicals for removing oxidation from steel are pretty nasty. We use a product called DMB (Descaler Metal Brightener). It’s effective and fast but probably a lot worse for the environment than cola.

  • http://twitter.com/rileyporter riley porter

    John, try household vinegar and then some NaCL or aka salt :) My three year old and I found an old penny that was pretty bad. Dipped it in there for a few minutes.. Stirring every now and then… It came out close to “clean” a bit more manual labor and it was pretty good!

    • http://www.facebook.com/profile.php?id=37705553 Scott Rocca

      Vinegar actually rusts steel. Its a great thing to use on copper, brass and other ferris metals but for a non-ferris metal like steel it will cause ruse. In fact you can use vinegar to remove the galvanization from steel simply by soaking it.

      • http://blog.whisperoftheshot.com Justin Cole

        I think you’ve got ferris and non-ferris mixed up.

        • http://pulse.yahoo.com/_VST4KFSIU4DASR6OAUCF2G6TM4 Griz

          I think you’ve got wheels and metals mixed up :)

      • http://dbcooper.livejournal.com P.F. Bruns

        I believe the word you seek is “ferrous.”

      • http://twitter.com/rileyporter riley porter

        Ahh yah… Copper it is.. ok DONT DO IT! :)

        ril3y

  • Anonymous

    If phosphoric acid were that good at removing rust, I would expect to find bottles of the stuff in my local hardware store being sold as ‘rust remover’.

    Alas, this is not the case…

    • http://www.facebook.com/ross.hershberger Ross Hershberger

      The DMB product that I cited has as it’s active ingredient Phosphoric Acid. It works extremely well.

      • Anonymous

        Actually, it wasn’t sarcasm, but I’ve never used Naval Jelly or DMB. I’m familiar with oxalic acid and citric acid as rust removers. But not phosphoric acid.

        Guess I need to get out more! ;-)

        • http://www.facebook.com/ross.hershberger Ross Hershberger

          Oxalic acid is sold under its own name but for some reason phosphoric is only in branded products. Too dangerous to sell in pure form? Dunno.

        • http://pulse.yahoo.com/_PZYK5NC4DSEK2FFYXGZ3MOSBSY FlatTop

          Naval jelly is fantastic, but it’s best used on simple shapes. Also, it leaves a film of iron phosphate, IIRC, that will protect the surface from flash rust for a while and since the surface has been acid etched, a self-etching primer isn’t necessary. This post explains it pretty well:
          http://www.metalmeet.com/forum/showthread.php?t=2257

    • http://pulse.yahoo.com/_PZYK5NC4DSEK2FFYXGZ3MOSBSY FlatTop

      This is sarcasm, correct? Naval jelly = phosphoric acid.

  • http://www.facebook.com/profile.php?id=589442653 Kevin Cooley

    Birchwoood Casey’s Blue and Rust Remover is the best rust remover I have ever seen. It’s sold as a firearm product, but it is safe to use on any metal. A little bit of it goes a long way. I think it would be perfect for tool restoration. You could even use some gun blue to coat the wrench when you’re finished. Or Dura-coat it. ;)

    http://www.cabelas.com/solvents-lubes-bluing-birchwood-casey-blue-rust-remover-1.shtml

  • http://pulse.yahoo.com/_LUZQBJGYFXNAXSL7YRVTAUPYJY d

    Try some Bar Keepers Friend cleanser. (contains oxalic acid)
    Darn handy stuff for removing rust, stains, etc.

  • http://www.drewbatchelor.com/ Drew

    I got good results with citric acid powder (in a plastic bucket of water), leave it overnight. Safe around kids. etc.

  • http://vrandy.myopenid.com/ VRAndy

    … Therefore rust removers are delicious. QED.

  • http://rahere.livejournal.com/ Rahere

    Ex Schweppes labs – the best we ever found was our Russchian mixer. The problem is the sugar interferes with the reaction.

  • http://rahere.livejournal.com/ Rahere

    Formerly of Schweppes Labs – Russchian was by far the best for cleaning coinage. The problem with sodas is the sugar masks the deeper sites.

  • http://www.advancedwebads.com/sc/164 Mel Webads

    Think of this people – rust is really a very harsh by product of water and iron and rust is poisonous. Now, rust can be removed by acid. Now, if Pepsi and Coke can actually removed the rust in tools, then it must have contain a lot of acid and could be harmful to the health.

    • http://pulse.yahoo.com/_VST4KFSIU4DASR6OAUCF2G6TM4 Griz

      If rust was poisonous we’d all die of blood.

    • http://dbcooper.livejournal.com P.F. Bruns

      The stomach also contains a lot of acid, but I haven’t died of one.

  • http://pulse.yahoo.com/_CIHPFRH3YOA4SGDLARMVHRT654 John

    Well, after hearing that you tried Coke, I had to chime in with my experience. One day my dad came home with an old bike for me ( I was about ten at the time). that apparently had spent too much time outside in the rain. My older (twelve) brother knew of the power of Coke, and since more is better, he suggested we add vinegar to the mix, too. What the heck…

    The specific target was the completely rusted handlebar nut and bearings assembly, which had to be removed so we could strip all the old paint from the frame with paint stripper. The Coke and vinegar combo was poured into the neck of the bike numerous times over a couple days, and sure enough, it finally broke free. We then spent many hours with wire brush and rag clearing the rust from the bearings and threads so it would all work properly when we put it all back together.

    Did the Coke / vinegar really have any effect? I don’t know, but it was fun to tell the story to all our buddies. The bike turned out pretty good in the end too. Candy Apple Blue. NNNNNNNice….

  • http://www.facebook.com/warts.genital Zac Cheong

    for the slightly less budget approach, an angle grinder and a wire wheel will get a much better result in a fraction of the time.

  • http://twitter.com/normnode Norman DeValliere

    With a wrench like that, the size of the opening is important, but unless it is collectible, I would feel fine about going at it with abrasives. WD-40, with wire brushes, steel wool (or the synthetic substitutes), and sandpapery things of one sort or another – any of these would make quick work of getting it clean of rust.

    Getting rid of the pits is fun too. If the milled sides of each end are in the same plane, you could lay the tool flat on an oilstone and lap it until smooth. But, you probably don’t want to make it look like jewelry :-)

  • Anonymous

    I’ve had decent results cleaning a rusted workbench with a small amount of diet coke agitated with aluminum foil. I chose diet coke because the sugar in regular coke seemed like it would be counterproductive. It may not make something magically gleam, but it’s less hazardous than breaking out naval jelly in an enclosed space.

  • http://profiles.google.com/atkinson.john86 John Doe

    I’m looking forward to see the final result, after the Mexican Coke. I suggest you to try to remove the rust with a solution of baking soda and vinegar, but I do not know if it will work.

    Regards from an Enfield cleaner!

  • http://pulse.yahoo.com/_GJTOUJ3NWFLOYX34NIW7YHI77U Argo c

    A product I’ve seen work real good , is from Nu-Calgon . It’s called liquid ice machine cleaner . It turns rust (iron oxide) into iron phosphate , which is a black looking material and it also blocks further rusting .

    The msds sheet identifies it as Phosphoric Acid , which is why cola kinda works .

  • Anonymous

    Pretty component of content. I
    simply stumbled upon your blog and in accession capital to say that I get in
    fact loved account your blog posts. I have ever seen. It’s sold as a firearm
    product, but it is safe to use on any metal. A little bit of it goes a long
    way. I think it would be perfect for tool restoration. Pretty neat to take a
    saw that’s totally red and covered in scale and in a day or two you can wipe
    off the rust, and read the stamped info. Thanks once more for the information
    and keep up the really great work. I will probably be returning and will check
    your further posts.

     
     

    microdermabrasion

  • Anonymous

    Pretty component of content. I
    simply stumbled upon your blog and in accession capital to say that I get in
    fact loved account your blog posts. I have ever seen. It’s sold as a firearm
    product, but it is safe to use on any metal. A little bit of it goes a long
    way. I think it would be perfect for tool restoration. Pretty neat to take a
    saw that’s totally red and covered in scale and in a day or two you can wipe
    off the rust, and read the stamped info. Thanks once more for the information
    and keep up the really great work. I will probably be returning and will check
    your further posts.

     
     

    microdermabrasion

  • Anonymous

    I’ve seen a few great blogs that don’t have comments at all.They have many readers and rust preventative no comments whatsoever.

  • http://www.rustterminator.com Vladimir Stefanovic

    I have been in the rust removal business for years, from developing products to marketing them. They are many options, sum easy but not safe and some easy and extremely safe. That is the route i suggest. Get a Non-toxic , acid free, solvent free rust remover and let it do its work. They are a few on the market. Some work better than others.

  • Jasmine

    I work among some large companies and currently they are using a non-toxic rust remover as well. I saw Valdimir posted about them above. One that we have found that works well and fits into our company budget is http://www.Rust911.com. Take a look and see what you think.

  • Anonymous

    May I know What is in the Coke that removed the rust?

  • Pingback: 20 Alternative Uses For Coca-Cola | Our Daily Ideas()

  • Benjamin Jones

    Why not just use a regular Coca-Cola – why a Pepsi or Mexican Cola?

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