Geoff's Science Garage - Electrolytic Rust Removal

[TheGLOCK17shooter]

Can this be used to derust the inside of a Honda shadow 600 gas tank that is HEAVILY rusted? What technique do I use?

[flamingidsnew]

Nice



[wildmandazza]

awesome...thanks heaps !

[QUABLEDISTOCFICKLEPO]

I was thinking about plating the bell by the same process, but that would obviously involve more than simply switching connections. Nothing is now being plated, so there must be something I'm missing. By the way, as is obvious I'm a complete novice at this, so I don't know what I don't know, need to know, or should know. When I spoke of danger, I was thinking of life and property. I was thinking of circuit overloads, blowouts, and fire. I'll just buy more pie pans for the anode.



[ggariepy]

You have to understand that it will remove the rust, but the metal that was rusted is gone. There will be pits instead of rust.

I would not use the 50 amp setting. It shouldn't pose any danger to the bell, however it should not be necessary.

You do not have to change the water. It does not aid in the process.

Is the steel anode becoming rusty? Hitting it with a wire brush *might* improve performance. I am not sure on that point, but I would try it. Also rotate the bell.

[QUABLEDISTOCFICKLEPO]

Well, I bought another battery charger, a manual one. This one has settings for 2, 10 and 50 amps. I've been running it for about four days, 2 amps at night and 10 amps during the day, but I've been reluctant to use the 50 amp setting. Anyway, after almost nonstop usage for about four days, my bell still isn't back to it's original condition. Bubbles aplenty, and rusty water (I keep changing it), but I'm wondering how long it will take. No complaints, I'm learning. Any danger if I use 50 amps?

[ggariepy]

I'd search on Craigslist for a good used unit, although a reasonably decent new one can probably be had for $40 at Harbor Freight, if you're in the USA.

[QUABLEDISTOCFICKLEPO]

Yes, it is steel, or iron, and magnets stick to it. It's  not a very attractive bell, but I'm doing this for a friend of mine, who has moved away. She had a sentimental attachment to it but didn't take it with her when she saw how rusted it had become. My idea was to derust it and to surprise her by sending her the shiny bell she once had. This is how I got into the electrolysis game. Now I'm just trying to find a reasonably priced charger or Ac converter. Any suggestions?

[QUABLEDISTOCFICKLEPO]

Now I know. When I bought my battery charger, I didn't know enough to make a good decision, I was only looking for a good price. I still don't know very much, but I've now learned the meaning and significance of "OUTPUT: 120 VDC@750mQA". It means that I bought the wrong battery charger. 750mA is only 3/4 of an amp, and that is apparently not enough to remove rust by electrolysis. Oh, well, live and learn.

[ggariepy]

By the way, this bell is steel?  I.E. a magnet will stick to it?

[ggariepy]

The charger you have is only 3/4ths of 1 amp. The process will work, but it will be slow. If you have an extra car battery, or can wire some 6v batteries up in parallel, they'll deliver more current and speed things up. The charger I used in the video delivers 10A maximum. Your iron nail probably was working, just terribly slowly.

Removing rust does not require high voltage, but current affects the speed. Incidentally, rust is itself an electrochemical process; you're just reversing it!

[QUABLEDISTOCFICKLEPO]

ggarlepy,

Thanks for the information. How about the charger settings? Are they okay for rust removing? (Note, I did try a large iron nail, but it didn't work. I guess size or surface area is also important). I thought I'd have to buy another charger, but the more I read the more confused I got about what would be appropriate to use for removing rust by electrolysis. I don't want to spend more money only to find that I've missed something.

[ggariepy]

The aluminum anode! It must be ferrous. Avoid stainless steel if possible.

*Any* old piece of steel will work.

[QUABLEDISTOCFICKLEPO]

Help.

I used an automatic battery charger (Output: 12VDC @ 750mA, Input: 120VAC @ 60 Hz 12 W). These settings cannot be changed. I completely surrounded the bell with a band of aluminum. I did not suspend the bell because the container is plastic. . For the electrolyte, I used one tablespoon of baking soda to one gallon of water, but when that didn't seem to be working I poured in my more baking soda. It didn't help.

What could be wrong? Charger settings? aluminum anode? Not suspended?

[flaxnard]

how much baking soda do u have to use

[ggariepy]

@flaxnard Try a third of a cup of baking soda to 5 gallons of water. Add a little more at a time until you start seeing the bubbling take place. Be conservative with it: the more you put in, the more current passes through the water, and it's possible to overwhelm your power source, i.e. pop the circuit breaker on a battery charger or burn any connecting wires too small to handle the load. Make sure you do this outside if you're going to leave it unattended at all.

[jeffddow]

hey if you use stainless steel rather than just normal it wont corrode and you can use it alot longer :)

[ggariepy]

12VDC

[00pyroboy]

What voltage are you using?

[miguelaltes]

What can i say?

Thank you.

[drako781]

good job....

[3DInteractiveGun]

Just gave it a try. Works fast

[AThunderA]

Good video! If I knew about that I wouldn't have stuffed up my hands sanding my exhaust manifold to get a crappy result and than make a baking soda paste that also doesn't seem to work weel either. I'll definetily will try this as soons as I get all the gear together! Cheers!

[ggariepy]

@AThunderA I'm pleased that even after 5 years this little video is still educating people. I never would have dreamed that over 60,000 people would see it. Good luck with your exhaust manifold, and be sure to use a container you can afford to ruin, as it does create stains. A 12V automotive battery will suffice for a power source if you don't have a battery charger, although it will run down and need to be recharged afterward. Greetings from Detroit! --Geoff

[jajanciar]

@AThunderA 

[swat253dg]

This process works well! I've used it many times, however; I went to a pool supply store and bought about 5 lbs of sodium bicarbonate. I used roughly 2 tablespoons per 5 gallons of water and the rusted parts come out very clean and rust-free!

Nice video!

[PRESTOALOE]

You, good sir, have a voice for radio. Dare i say a face for radio as well? Jk. Great video.

[Zox604]

Thanks a lot. I did it in ceramic cup and no stains on it. I have no soda and did it with sodium bicarbonate. It WORKS!

[ggariepy]

@Zox604 Congratulations. Glad to hear it worked for you. It's a reasonably reliable process, I've never had a failure over the many times I've used it since making this video.

[Mentorcase]

Immerse part in solution KER-PLUNK .......AH,MY EYE!

[starbuck77777]

It appears that both terminals are above the water line. Wouldn't the ick that is produced by the electric and chemical reaction foam up to the terminals and cause them to short circuit?

[ggariepy]

@starbuck77777 No, the foaming happens very slowly. By the time it would be possible for that to happen, the rust is pretty much all gone anyway.

[ggariepy]

The process will remove the paint and the rust, given enough time to work. It loosens the bond the paint has, and then it peels up in strips. I think you're further ahead if you hit the paint with a wire brush first though, it will speed things up.

[badderthanyou]

Does this get the rust under the paint?

[watsupstartaketwo]

Hi, can you do this in a bathtub? Do you know if the rust will stain the enamel? Thanks.

[ggariepy]

@watsupstartaketwo: Don't do this in any container you care about, especially a bathtub. My original bucket was stained permanently. I'm sure the bathtub would not fare well.

[watsupstartaketwo]

@ggariepy woah, thanks :D lucky i didn't get impatient and just try it :D

[kbot6789]

wow i need a new keyboard um a 70 amp psu and a 50 gallon plastic drum

[kbot6789]

hi guys thanks for the info man worked great in my used bike shop now im planin on makeing one out of a 70 am computer powersupplu and a plastic 500 gallon drum just for bike frames saves a ton of elbow greese if you guys want pics of how i did it just let me know

[DarkAngel182]

I assume some sort of rust resistant primer would be best for the base coat once the rust has been cleaned off?

[loco0351]

Wow i know i should have paid more attention in chemistry class. oh well thank you very much i have learn something.

[pow0006]

wouldent adding salt into the mix make chlorine gas?, since salt is made from sodium and chlorine.

[318Captain]

I think you might mean sodium chloride. But Idk if thats the same.

[gatorman21218]

No in order to decompose salt it needs to be a liquid. you will not produce any chlorine if its dissolved in water

[Shinigami117S]

thanks!

[MYSOFA]

Hmm, looks like curry in a bucket. Good idea!

[elywhit1]

i watched your video and tried it, it seems to work very good . i am restoring a 50 yr old kids trike the wheels are rusted and the tires are solid rubber and can't be removed will the process harm the rubber?

[ggariepy]

It won't do the rubber a bit of good, but it's hard to say for sure whether or not it will be harmed. The process takes paint off metal fairly well. If the trike's tires are like the ones on pedal cars, they can be removed by cutting them off. There are replacements available for pedal cars; I wouldn't be surprised if there were for tricycle tires as well. Good luck!

[wolfman852010]

@ggariepy

I've done this several times and it wont harm the parts the negative cable is connected to.

[abeltri]

Can´t way to try, I found more old nice rusted pieces to bring back to life than I thought.

[spinafire]

5* I have Eben trying to find out how to do this, it's very helpful :D

[berkelusa]

Add some Salt and make the water more conductive and the process will go much faster.. and not much Salt.. like a tablespoon.. -Rob

[Xonegod]

Thank a ton for this tip, I know most who will use electrolytic rust removal will thank you, under their breath, in unison. :-)

Further note: make sure that if you use salt for increased conductivity, to get the polarities of the part and electrode right the first time or risk having your part desolve, quite literally, before your eyes.

..X..

[SkinnyPimpYYZ]

how much baking soda??

[Xonegod]

A table spoon per gallon of water. You may use the solution perpetually for multiple parts but eventually it will depleate the water through evaporation, the washing/baking soda will not deplete. Therefore you should add more water to maitain the aforemention ratio, but do not add more W/B-soda as it will not benifit your rust removal operation. :-)

After a few parts however, you will probably want to dispose of the solution because of crud.

Next time use Google its ur friend~!

.X..

[spartaeus]

Does this process also remove metal from the part if kept on too long?

[ggariepy]

No. Eventually what will happen is the sacrificial anode will disintegrate and the circuit will be broken.

[BobsAutoRepair]

Cool!

[bogusjunk74]

I've tried that, but actually works alot better if you put a battery inline to maintain a proper continious clean voltage. Though I'd highly suggest Muriatic acid for rust removal, it's instant, and the stuff you buy at lowes or home depot is a deluted safe form, work in 1 minute intervals, i just spray it on, then rince it off, instantly removes the rust, just dont keep it on longer then 2 minutes or it will discolor and etch the original metal like chrome or anything else and seal instantly.

[Xonegod]

The difference between muriatic acid and electrolytic rust removal is that the former removes the rust compleately and seperates it from the "Good" metal. The latter of the two actaully restores the rust closes to the host metal back to actual metal state. Less pitting and deterioration of the patient part is the result.

It should also be noted that after a piece of metal goes trough the electrolytic rust removal it should be stabilized with paint or oil imediately after.

..X..

[americanmadeZ06]

I have a coupe body that I am trying to remove all the rust to make into a hotrod. If I make a huge tank and put the whole body in it. There will be some spots where I can not get that black goo off. Like cracks and crevices. If I just leave it there will it rust again or what will happen. Please respond if you know. Thanks.

[ggariepy]

Rust happens when metal is exposed to the elements. If the metal is properly sealed with a coat of paint, it cannot rust. However, you have to get it to the point where the paint will adhere. I don't know what this thing looks like or how many cracks and crevices you're talking about. If there are blind spots the process won't work in them anyway. Most people doing an entire car have the body acid dipped for this reason.

[Chronicdiving]

The mixture I use is 1/2 cup sodium carbonate(you can get this by baking baking soda over 300 degrees for over an hour) to ever 5 gallons. you have to be careful with tools like copper and chrome 'cause you can be left with chlorine gas and chromium and chromium is illegal to dump 'cause it'll fuck up a well or a water table.

[wakka922201]

Sodium carbonate is better; it doesn't muck up the solution as much. Also, hexavalent chromium is very toxic. So yeah, don't use stainless steel or anything w/ chrome. It will do more than fuck up a well or water table.

[gasperstifter]

What's the ratio of mixture? watter:soda

[ggariepy]

In a small 2 gallon bucket like the one I had in the video, a cup or two is more than enough. For really BIG derusting (you can do an entire car at one time, provided you can build a big enough tank) you will need a considerable quantity, but I don't know how much. Start out small and experiment. By the way, the bucket is no longer pretty after you use it for this, as it is heavily stained by the iron residue. Don't use the wife's good buckets!

[fmjkevlar]

i used spirits of salts (sulphuric acid) i find that work amazingley, give that a go.. you'll be immpressed!

[aatoys001]

AAAA +++

[baman12]

Hi mate I'm from the UK and I built a similar electrolysis device in a bucket! To de-rust a load of old spear gun. There almost like new now and I saved around £80 in terms of actual rrp! however if you add more anodes around the circumference, and then suspend your part in the centre using a piece of wooden dowel with a cable tie to hold your cathode cable in place, you will get full 360 degree cleaning and also a lot faster to boot. Also table salt works perfectly well.

[79camaro454]

Now would this work on tools too, like chrome, or the "Craftsman" finish (not chrome but not bare metal). If you do it to your tools, will they rust over in a few days again?? And what about disposal?

[ggariepy]

Any unprotected metal will re-rust quickly, especially in a wet or even just a humid environment. The process has been used successfully in a wide variety of applications, so I would experiment with whatever you have; if it's ferrous rust, it should work. As far as disposal is concerned, the liquid is ferrous-rich water, and isn't hazardous to most forms of plant life. You can re-use the same liquid over and over again for future de-rusting projects, or just dump it out on the lawn.

[rshubbee]

Great, thanks!

[jackscrew]

I slept through chemistry, so I'm wondering what you are left with in the bucket. Does it require any special disposal?

[lVlagneto]

I THINK that you're left with a lot of oxide slime (depends on what you're cleaning).

I've also heard that mercury can be released if you use a stainless steel rod as your anode.

Thanks for posting this video. I usually use a little 12v wall adapter, but a battery charger is a much safer alternative.

[moonshin13]

Very nice demo, good job.

[brandoblues]

thats pretty cool