Electrolytic Rust Removal aka Magic

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:

http://www3.telus.net/public/aschoepp/electrolyticrust.html

http://myweb.tiscali.co.uk/andyspatch/rust.htm#top

http://antique-engines.com/electrol.asp

Comments

[maverickcanakay]

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

[cmuldoo]

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]

one more thing re copper - and I dont know squat about this statement, but am curious about this guy's take on it:

http://www.rickswoodshopcreations.com/Miscellaneous/Rust_Removal.htm

"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."

[ToolNut]

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:

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

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...

[SvenPetersen]

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]

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.

[PitStoP]

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

[wb8nbs]

I've used electrolysis a lot for old tools I get for next to nothing at garage sales. My main tank is a five gallon bucket with 6 inch wide steel plates on either side. I have plastic grids cut from a milk crate attached to the the plates to lessen the danger of short circuits. I have made odd shaped tanks from wood, for example a long shallow one for de-rusting hand saw blades. Salvaged a couple of vintage Disstons with that. Just lined the crude wooden trough with a thick garbage bag.

I set up the tank with the work piece inserted and fill with water from the garden hose. The carbonate does not dissolve easily in cold water. I get a half gallon of hot water and dissolve a handful in that. Then add slowly to the main tank until the charger current comes up to what I want. I have an old 6 amp 6/12 volt charger. I don't know the chemistry either, but believe the lower voltage works better, and it is really amps per square inch of tool surface that controls the process.

I pull the tools out about every half hour and give them a light scrub with a brass bristle brush. The brass won't scratch cast iron. You can find good brass brushes at stores selling barbeque grills. Watch that they are not just brass plated steel though. If you scrub the piece while it is wet with carbonate, some of the brass will plate over onto the iron, giving it a slight yellow cast. I think it looks antiquey. If you don't like that idea, rinse the piece well before brushing.

[rayray98]

What will this process do to rubber, on a part like a brake caliber?

[rdm_box]

As you comment is so old, this probably won't matter to you now, but I just thought I'd say that the electrolyte may cause the rubber to perish and become hard and brittle.

[jeff-o]

I doubt it would do anything - the rubber is non-conductive and would not take part in the chemical reaction. Be aware, however, that the bike components are often a mish-mash of different metals and your results may be undesirable depending on what those metals are.

[corey11]

Exactly. Since some metals in that mish-mash are more conductive and less conductive that others, they would, technically at least, produce either more or less of an electric current therefore some parts would 'disintegrate' (in lamens terms) faster or slower than others.

[Kevanf1]

Couple of things you may (or may not of course) like to know :) First, if you have a complex piece of metal (odd shaped tool or something) that you can't properly polish up then you could always use epoxy resin to fill in the 'pits'.

Second, if anybody is worried about using mains electricity this will work just as well with a car battery; as long as it has some decent amount of charge in it of course :-)

Very good ible, well done.

Thank you and take care.

Kevan

[ToolNut]

Thanks and good thoughts on epoxy.

[Kevanf1]

Just something I remembered from long, long ago in my motorbiking days. Epoxy used to be a fall back if telescopic fork stanchions were slightly pitted but not really bad enough to warrant complete renewal. However, back then I didn't know about this method of rust removal and I wish I had. This would give a far, far better surface for the epoxy to adhere to.

Once this weather warms up I have some Land Rover wheel drums (brakes) to de-rust. 11 inch ones...

Oh, another thought. How about a piece of sheet steel inserted into the bucket so it encircles anything you want to derust? You'd get full line of sight for the object that way with no voids. Just a thought :-) Or even using a steel (not galvanised though) bucket or large industrial paint tin.

Take care.

Kevan

[Luke29]

Could this process be used to remove a chrome plating from aluminum? thanks.

[geekdude]

so could i do the same thing with a computer power supply and a power strip in place of a gfci outlet? hmmm i think i have a ups around here somewhere im not useing or mabye i should find a car battery. my house is to old to have gfci outlets

[VadimS]

PC power supplies are totally isolated, so a gfi breaker is not needed but doesn't hurt to have one.
Use the 5v for small parts and 12v for larger items.

A power strip is not a gfi unless it specifically says so.
A power strip (or bar) usually has a breaker wich shuts off if more then 10 or 15a flows but a gfi (ground fault interrupter) detects leakage current, ie. power that is not returning on the same line that it came in. So if you use a gfi and connect one lead to a metal pole in the ground or any other line (like you) that bypass the gfi it will shut off.

I wouldn't recommend a ups system, they have a lot of internal circuitry for testing the battery, and would probably not work.

[geekdude]

i ended up finding a car battery charger and wiring a gcfi outlet to the end of an extension cord. it worked well until winter came. im still waiting on warmer weather so i can de-rust some stuff. without making a big salty ice cube.

[DELETED_gabethegeek]

(removed by author or community request)

[rocketguy]

Actually you do need to reach a threshold of voltage to overcome the resistance of your skin before you're affected by any level of current. While anything with a lot of amps is due some respect, if it's at, say, 4 volts, it's not likely to fry you, unless you've managed to really douse yourself in salt water and stuck your fingers in the wrong places. The effects of electrocution vary with voltage levels as well as type of current (ac vs dc). AC is potentially more dangerous due to interference with cardiac rhythms, but below 50 volts this is unlikely to happen. At higher voltages nerve induction does nasty things, and then at even higher voltages it just burns the hell out of you, without much penetration into the internal organs. Of course if you have both voltage and a ton of amps you can be entirely vaporized, as happened with an individual who threw the breakers on a very large printing press... while they were still running. The inrush current resulted in an arc discharge much like a tiny nuclear explosion, vaporizing pretty much everything in a small radius around the breaker. They found his boots melted to the floor, feet still in. All that said, is it really so hard to just use some rubber gloves?

[tmn8tr]

awesome instructable. You've given the basic DIY'er the ammo as well as the confidence to build their own Electro-Stripper! Don't worry too much about the electricity, as you've already stated it IS VERY important to be hooked up to a GFCI outlet, and keep your power source from 1.5-5 amps. A person could also use anywhere from one - three 12v automotive batteries, depending on the size of the piece of metal. This is how it was done in the "old days". What you have here is essentially an electro-plating bath, without the hazardous Potassium Cyanide solution. You are essentially plating the rust onto the re-bar. (That ought to get some brains warmed up.) anyway, nice job!

[ToolNut]

Thanks!

[Jmiller87]

I am thinking about using this to clean up some old truck wheels and was wondering what effects at all on Chrome?

[ToolNut]

Cant remember if I mentioned this somewhere before now, but I understand that the chrome can react and create a very hazardous chemical compound. I would NOT put anything chrome in there. I'll try to post a reference link soon. Thanks for asking!

[Jmiller87]

Thanks, I'm not really sure what the wheels are, I would imagine they are either steel or chrome but all the snow melt has taken a major toll on my wheels this year!

[ToolNut]

Now that I think more - I think it may have been stainless steel that you should not use. I still wouldn't do chrome until you confirm that it will be safe.

[Prfesser]

Correct, do NOT use stainless steel or other chromium-containing metal as the anode.  You end up with a solution of chromium ions which must be disposed of as toxic waste.  [Green chromium(III) isn't so bad -- it's used as a pigment in some cases -- but orange or yellow chromium(VI) is carcinogenic]