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i just finished reading the cummins 5.9 swap into a suburban. this guy goes into great detail with this engine port polishing polishing the rods custom turbo header all kinds of stuff.

but he shows how he cleans a rusted cylinder head.


he took a plastic tub. filled it with water and lunadry powder.

then took a automatic battery charger. he hooked the cathode (postive) to the rusted part. he hooked the "anode" (negative) to a piece of stainless steel for use as an electrode to attrack the rust. i understand the process. the current travel through the cylinder head and pushes the rust off. repels it. it is attracted to the stainless anode. if u pulled the anode out you would see rust particles sticking to it. and part would be chemically cleaner.


i have tried this on a smaller scale as a siple experiement to create hydrogen and then burn the stuff. it does work. but since i was using copper anodes and cathodes the copper corrodes easily. wires broke down pretty fast. but you can see the water breaking down into the more simple elements of hydrogen and oxygen and then ya can burn em.



but seems like a great automotive use of electrolisis to clean metalic parts.

could prolly clean a corroded radiaotr same way i dunno.

some where there was a list as to which metals use a positive and which use negative. maybe it was in my chemistry book. i dunno.
 

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because dodge doesn't build a suburban fighter thanx to GM.... thats the ONLY reason i would buy chevy... the suburban.... if dodge built one i would own it in a heartbeat.
 

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Thats interesting Joe. We do a similar electrocleaning process here at work to clean our gears as part of our copper plating process. I never thought it would remove rust though! 8)
 

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Hmm, there's a few problems with this... In the picture you posted, Joe, it is set up with the part as the anode (which is actually positive), and the steel as the cathode (which is negative).. The part MUST be the cathode, and the steel MUST be the anode.. The anode is sacrificial in electrolysis, which means it dissolves during the process. You don't want your part to dissolve, do you?? ;D The other thing is, YOU SHOULD NOT UNDER ANY CIRCUMSTANCES use stainless steel!! People say it's the best because it stays relatively clean and doesn't dissolve, but it actually does break down. When stainless is used in electrolysis, one of the byproducts released into the water is Hexavalent Chromium. This is a very poisonous metal, and it is illegal to dump in any municipal or private drain system because it classified Hazardous Material. When it gets into the groundwater, it can contaminate wells for miles in all directions, very much like MTBE does around gas stations. The main difference is, Hexavalent Chromium causes cancer and numerous genetic problems which can be passed on to future generations. Ever see the movie "Erin Brockovich" with Julia Roberts? That was a true story. If you want to see what that crap does to people when it gets in the water, watch that movie. Just stick to using Iron. That you can dump in your yard and it won't do anything.


Hexavalent Chromium OSHA info here

Chromium MSDS
Matt {peace}
 

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TaZMaNiaK said:
Hmm, there's a few problems with this... In the picture you posted, Joe, it is set up with the part as the anode (which is actually positive), and the steel as the cathode (which is negative).. The part MUST be the cathode, and the steel MUST be the anode.. The anode is sacrificial in electrolysis, which means it dissolves during the process. You don't want your part to dissolve, do you?? ;D The other thing is, YOU SHOULD NOT UNDER ANY CIRCUMSTANCES use stainless steel!! People say it's the best because it stays relatively clean and doesn't dissolve, but it actually does break down. When stainless is used in electrolysis, one of the byproducts released into the water is Hexavalent Chromium. This is a very poisonous metal, and it is illegal to dump in any municipal or private drain system because it classified Hazardous Material. When it gets into the groundwater, it can contaminate wells for miles in all directions, very much like MTBE does around gas stations. The main difference is, Hexavalent Chromium causes cancer and numerous genetic problems which can be passed on to future generations. Ever see the movie "Erin Brockovich" with Julia Roberts? That was a true story. If you want to see what that crap does to people when it gets in the water, watch that movie. Just stick to using Iron. That you can dump in your yard and it won't do anything.


Hexavalent Chromium OSHA info here

Chromium MSDS
Matt {peace}
True about the polarity Taz, you then need the positive as (sacrificial) anode. And the negative to the rusty part to clean.

Good info to steer clear of Stainless as the positive and use mild steal or rebar.

http://www.angelfire.com/tx/hotube/electro.html

For additional info,
 

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Interesting points Taz, however, if the part becomes the cathode, there is no cleaning action of the part, so if you're doing this to clean, the part must be the anode.
As I mentioned in my other post, we have an alkaline electroclean that we use to clean aerospace gears before plating. At this stage, these gears are maintaining tolerances of .001"-.004", some are even less than .001". Obviously if material removal was an issue, we wouldn't be doing it.

I think their are two issues here that make this practice acceptable:
1-Length of time being energized
2-And more importantly, what the bath is made up of.

For an accelerated material removal rate to occur, it needs to be done in a bath made up of something that is quite corrosive to the material that the anode is made out of. Laundry detergent is not very corrosive to steel/iron.
Also, what about anodizing? It is called this because the part is the "anode". Now there are some chemistry things taking place here that I cannot explain, but if you look at the anodize process, it tells you that its not as simple as you (or even me, for that matter) explain.
In anodizing as I explained, the part is positive and the bath is negative. A piece of Aluminum is placed in a bath of sulfuric acid (Type II anodize), which, strangly enough, IS corrosive to the Aluminum. During the process, a high amount of current is passed through the part and the anodic coating forms on the part. Oddly enough, the anodic coating not only penetrates the Al, but it also BUILDS UP as well. Yet if you leave the Al in the bath without current going through it, it will slowly dissolve the Al away.
I don't understand the science of how current going through the part keeps it from being etched when it is in a corrosive solution, but my example shows "its not that simple". ;)
 

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KThaxton said:
Interesting points Taz, however, if the part becomes the cathode, there is no cleaning action of the part, so if you're doing this to clean, the part must be the anode.
...
Also, what about anodizing? It is called this because the part is the "anode". Now there are some chemistry things taking place here that I cannot explain, but if you look at the anodize process, it tells you that its not as simple as you (or even me, for that matter) explain.
...
Oddly enough, the anodic coating not only penetrates the Al, but it also BUILDS UP as well. Yet if you leave the Al in the bath without current going through it, it will slowly dissolve the Al away.
Not to put you down or tell you what's what, but you just contradicted your incorrect first statement with a correct second statement. The anode is always going to attract the material that is released from the cathode. When you "anodize" aluminum, the part to be anodized is positively charged, and it attracts the ions that are released from the cathode (usually the entire tank is made of aluminum or lead, and is electrically negative). For this reason, if you want to release rust from a part, you want it to be the cathode. The anode rod will attract the rust, which is why you have to monitor the current draw during the process.. The more rust gets coated on it, the less it will conduct...

I just found this neat page on "Homebrew Anodizing", where he shows you how to do it, and even sells the supplies pretty cheap. I think I'm going to give it a try on the aluminum parts of my bike.

http://www.focuser.com/anodize.html

Matt {peace}
 

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Not to put you down or tell you what's what, but you just contradicted your incorrect first statement with a correct second statement
I assure you, my first statement is correct, the part must be an anode if it is to be cleaned, otherwise, it is attracting ions from the bath which won't do much for cleaning.
The anode is always going to attract the material that is released from the cathode.
You've got it backwards, you even contradicted your first post.The anode is NOT attracting, the electrons are moving away from the anode to the cathode (it is sacraficial, as you stated in your first post).
Think of a normal plating process (which is the opposite of eletrocleaning). I'll use copper as an example since I used to do this for a living:
You have a bath with copper in solution. You have copper anodes (although they don't HAVE to be copper). You put a part in...In order for it to attract the copper from solution, it MUST be negatively charged. The bath (and anodes) MUST be positive, since current goes from positive to negative. Over time, your anodes have been sacrificed because they have been giving up their metal.
In an electrocleaning process, you are doing just the opposite, you are removing a VERY small amount of material from the surface (i.e. rust) in order to clean it. This requires the part to be positively charged (anode), so the material can leave the surface.
 

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While what you say is true for electroplating, with electrolysis you are not removing any of the base material. I'll try to explain simply, but it's still going to sound confusing. What you are doing is breaking the electrochemical bond between the iron in the steel, and oxygen. Rust is another name for ferric oxide (Fe2O3) When oxygen is "reduced", or accepts electrons from another element, it makes oxide (O--). Oxygen likes to be "reduced". If we put oxygen together with iron metal, the iron is oxidized (gives electrons to the oxygen) and the oxygen is reduced (accepts the electrons lost from iron). Whenever something is oxidized, something else must be reduced. Electrons must come from somewhere (oxidation), to go somewhere (reduction). Electrolysis reverses the oxidation/reduction process with electrodes submerged in water and washing soda solution. The anode is hooked to the positive wire of the battery charger. The positive wire accepts electrons. If the positive wire is accepting electrons, then something is losing electrons (oxidizing). When 12 volts is applied to the anode, water is oxidized at the anode surface and gives electrons up to the anode. The product is oxygen. The bubbles you see coming from the anode are oxygen that resulted from the oxidation of water. (The oxygen occuring here also promotes oxidizing of the anode rod, which is why it is sacrificial in electrolysis.) The other electrode is called the Cathode. In our case, the part we want to remove the rust from will be the cathode. The cathode is connected to the negative wire of the battery charger. The negative wire supplies electrons. So something must gain electrons at the cathode (reduction). (This also means that electricity flows from negative to positive, not positive to negative...) Two things are reduced at the cathode, water and the rusty iron. The reduction of water produces hydrogen. The bubbles coming from the cathode are hydrogen gas. The rusty metal takes on electrons and is no longer attracted to the oxygen atoms (which migrate toward the anode to oxidize it and the water), and the bond is broken. The rust is "reduced". During electrolysis the rust turns from orange to black. In most cases, the rust next to the iron is reduced to iron metal. This reduced iron will form a somewhat porous layer of new iron on the metal object being cleaned. After electrolysis the iron object will rust very quickly unless it is protected because this porous layer of new iron has a high surface area. The rest of the rust may reduce to a variety of compounds depending on the compounds in the original rust and the details of the electrolysis. Typically the black stuff that can be rubbed off after electrolysis is a mixture of iron metal and magnetite, (Fe3O4), an oxide of iron. Magnetite is an intermediate product in the reduction of rust to iron metal.It's the black stuff in magnetic recording tapes. So once your parts are cleaned or removed from the solution, you'll want to rinse and brush them off to remove the loose iron, dry them quickly and completely, and protect them with primer or other rust preventative. This process is also self-limiting.. There's no way to leave the part in too long, because once all of the rust is reduced, nothing else will happen (aside from the water continuing to reduce and oxidize, producig hydrogen and oxygen - and even that will stop once the anode rod completely disintegrates). Anodization and electroplating, on the other hand, have to be carefully timed. Once you reach a certain thickness of the coating, it will begin to pit because the acid is attacking the coating faster than it can be deposited.

Make any sense?

Matt {peace}
 

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Dodge78 said:
here are a couple of sites about electrolysis. The first one has some good pictures. The second one has some good info. All the sites I have seen vary the solution and have different opinion about using stainless.
http://www.rowand.net/Shop/Tech/Electrolysis.htm
http://myweb.tiscali.co.uk/andyspatch/rust.htm
Both those sites say not to use stainless.. For the same reason I mentioned, which is the production of Hexavalent Chromium. It is NASTY stuff, and you don't want to have to touch it, breath it, or dispose of it. It's a hazardous material that you have to pay a disposal facility BIG $$$ to get rid of it. If you dump it in your yard just once, you can potentially contaminate an entire city's drinking water supply, and be subject to lawsuits, cleanup fees, and even jail time. And yes, they would be able to figure out where it came from. But even still, you definitely would not want to drink, cook with, shower in, swim in, or even wash your truck in water contaminated with this stuff. Do yourself and everyone else in the world a favor, and don't use stainless for electrolysis. Iron works just as well, and will last for several cleaning cycles.

Matt {peace}
 

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Aaahhhh, the smoke has cleared!, It appears as though I’m arguing about the wrong process. ::) Electrolysis vs. electrocleaning, I should have paid more attention to the title, my bad. I assumed they were using the same process as we do to clean our gears (note in my first post how I said “I didn’t know it would work on rust").
Now that I read your reduction/oxidation explanation, I now see how they are two different processes, since I am also familiar with redox. We use redox to convert hex chrome into trivalent chrome, then get it to come out of solution. The only real difference is we don’t need electricity to do it, its all done chemically.
Basically, we are both right, except that I was right about the WRONG thing, D'OH! :-[ ;D
 

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I like this process of cleaning parts and like other projects I read as much as I can on them before I start them. If there something that seems dangerous in the process I investigate further. I am just trying to find the best solution and process for this.
This guy says he is an electrchemist, and under the anode section states" The most simple anode to consider is an anode made of stainless steel. In this case, the anode is inert, that is, the stainless steel does not undergo any chemical reactions." He either does not know what he is talking about or thinks everbody reading it already knows about the danger of using stainless. But most likely he is using formulas to come to the conclusion.
http://www.holzwerken.de/museum/links/electrolysis_explanation.phtml
 
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