Rust Removal using Electrolysis on a large scale

[hawaiioutdoors]

I've been reading up on different ways of rust removal.
This electrolysis rust removal using a DC welder as a power source seems pretty cheap and effective . Here are some links
http://antique-engines.com/trailer-electrolysis.htm
http://antique-engines.com/electrol.asp

[Wildman]

Very trick, even on a small scale that could work for all sorts of parts with a 5gal bucket... It would also allow for the cleaning of the inside a '40 frame for galvie diping... very interesting.

[Gumby]

Couple of threads on this about a year ago when I did my 40 frame.

http://forum.ih8mud.com/showthread.p...c+rust+removal

It does work better on a small scale. In fact, it works really damn well as big as a 50 gallon container.

The whole frame was kind of a bitch. The inside does not get done really well as it's mostly a line-of-sight kind of thing with the electrodes.

[yotawheeler]

ok so...if i read that right you hook up the positive lead to the re-bar or whatever piece of steel that just touches the water and then the negitive up to the wire that goes to the part....iv seen this before and thought it was a cool idea but also read that it CAN weaken the part being cleaned due to a chemical change in the steel...great for body parts ect. dunno if it would be the best idea on a frame because of this but great for body parts

[Coolerman]

There are few parts on my Cruiser that have not or will not soon goto into the de-rust tank. Been doing this for a litlle over a year. I have parts in a tank aS we sit.

http://tinyurl.com/5vpa7 Check it out, the tank is super simple to set up. I am using a 32 gallon trash can. There is a radiator shroud in the tank right now.

[Gumby]

Originally Posted by yotawheeler

ok so...if i read that right you hook up the positive lead to the re-bar or whatever piece of steel that just touches the water and then the negitive up to the wire that goes to the part....iv seen this before and thought it was a cool idea but also read that it CAN weaken the part being cleaned due to a chemical change in the steel...great for body parts ect. dunno if it would be the best idea on a frame because of this but great for body parts

The part that goes in the water needs to be IN the water, not just touching it. The closer to the part and the more it surrounds the part, the better.

[Pin_Head]

The electrolysis causes hydrogen gas production at the cathode (your derusted part), which diffuses into the metal and can cause the metal to be brittle, but the hydrogen diffuses out slowly over a few days, so the metal goes back to normal.

[Coolerman]

Originally Posted by Pin_Head

The electrolysis causes hydrogen gas production at the cathode (your derusted part), which diffuses into the metal and can cause the metal to be brittle, but the hydrogen diffuses out slowly over a few days, so the metal goes back to normal.

Yep, baking the part can help the hydrogen diffuse out. Since I'm powder coating anything that will fit in my old oven, I'm not too worried about that!

I found out about this from an old thread on the LCML. A search provided me with many links to tractor restoration sites. I had a tank running soon after.

The process does not get rid of rust so much as it converts the rust to a different type of iron oxide that is very tough. Any loose rust can just be wiped off the part when the process is finished. The nice thing is it gets under edges where a wire wheel or blasting may not.

You can de-rust parts even on the inside by using stainless wire threaded down through a plastic tube that has notches cut into it. The tube is inserted into the part and moved around every few hours. This allows the wire contact with the solution but not the part allowing the electrons to flow.

[tucker74]

Wow - this really works! I did some parts this weekend in a 5 gallon bucket, used some 22 ga sheet metal for my diode and a 10 amp charger ... all clean in 2-3 hours. I did a completely flaking with rust e-brake backing plate I got off a junk 40, which now looks brand new!

Thanks for the tip - no more blasting small parts for me!


Tucker

[Coolerman]

I actually de-rust then media blast the parts! Cuts the blasting time to almost nothing. There a few faster, safer ways to remove old layers of paint than this method. It does NOT work well on firmly adhered original paint however...

A bit of advice, DO NOT place ANY brass, aluminum, pot metal or copper part in the de-rust tank to be cleaned EVER!!!!!! It will destroy the part and contaminate the tank.

Tip: DO NOT use copper wires to connect the parts if the wires will be in the solution. The copper will disassociate itself and plate the steel part causing dissimilar metal corrosion in a hurry! Always use stainless or steel wire to connect parts.

I scored a large (15 gallon) solid stainless milk kettle from a friends farm a couple of weeks ago. Now I no longer have to add sacrificial iron, I just attach the + lead to the side of the kettle and hang the part in the solution from the - lead!

[Cammy]

Saw some mention of NOT using stainless in one of the links but didn't see why.

Will the stainless in your new tank deteriorate over time? There is a place here locally that gets all kinds of industrial pieces parts as salvage. I guess I'm looking for a tank now.

Anybody ever dip their tub like in the first link? I have some floor corrosion I'm thinking of converting.

[Teebag]

Why not SS

Why you should not use stainless steel electrodes for electrolysis
Many people using the electrolysis method for rust reduction swear by stainless steel, stating (incorrectly) that it's not consumed, stays clean and seems safe.
Stainless steel is indeed consumed when used in the electrolysis process, although slowly. The main problem with using it is the hazardous waste it produces. Stainless steel contains chromium. The electrodes, and thus the chromium is consumed, and you end up with poisonous chromates in your electrolyte. Dumping these on the ground or down the drain is illegal. The compounds can cause severe skin problems and ultimately, cancer. Hexavalent chromate is poisonous. These compounds are not excused from hazardous waste regulations where household wastes are.
These compounds are bad enough that government regulations mandate "elimination of hexavalent chromate by 2007 for corrosion protection."

Does your electrolyte turn yellow? That's a sign of chromates.

If you have been using stainless steel for the anodes (positive electrodes), wear rubber gloves when working with or near the liquids. If you need to dispose of it, allow it to evaporate into powders and dispose of the powders in sealed containers during your local "hazardous waste clean-up days".

Best bet - don't use stainless steel no matter how tempting it is.

[laguna80]

Crasy ass mechanic chemists! :flipoff:

[trekker]

Tip: Double check your connections and ENSURE that they are connected the right way!!


---------------- then check again! -----------------------


Your hard to find part may dissappear is you wire it up wrong! I learned this the hard way.

[Coolerman]

Originally Posted by Cammy

Saw some mention of NOT using stainless in one of the links but didn't see why.

Will the stainless in your new tank deteriorate over time? There is a place here locally that gets all kinds of industrial pieces parts as salvage. I guess I'm looking for a tank now.

Anybody ever dip their tub like in the first link? I have some floor corrosion I'm thinking of converting.

Quote:
Why you should not use stainless steel electrodes for electrolysis
Many people using the electrolysis method for rust reduction swear by stainless steel, stating (incorrectly) that it's not consumed, stays clean and seems safe.
Stainless steel is indeed consumed when used in the electrolysis process, although slowly. The main problem with using it is the hazardous waste it produces. Stainless steel contains chromium. The electrodes, and thus the chromium is consumed, and you end up with poisonous chromates in your electrolyte. Dumping these on the ground or down the drain is illegal. The compounds can cause severe skin problems and ultimately, cancer. Hexavalent chromate is poisonous. These compounds are not excused from hazardous waste regulations where household wastes are.
These compounds are bad enough that government regulations mandate "elimination of Hexavalent chromate by 2007 for corrosion protection."

Does your electrolyte turn yellow? That's a sign of chromates.

If you have been using stainless steel for the anodes (positive electrodes), wear rubber gloves when working with or near the liquids. If you need to dispose of it, allow it to evaporate into powders and dispose of the powders in sealed containers during your local "hazardous waste clean-up days".

Best bet - don't use stainless steel no matter how tempting it is.

Yes the SS is very SLOWLY eaten away. But all I do is pull my electrodes out once a month or so and wire brush the fur off them and put them back. When I clean out my tanks I allow the tanks to settle, siphon off the water into another container until there is about 5 gallons left. I then poor the sludge (dirt, grease, old paint, rust) into a 5 gallon bucket which is allowed to evaporate, mixed with sand and as stated let it be picked up during hazardous waste day. The siphoned off electrolyte is put back in the tank and fresh water/sodium carbonate mix is added to top it off. I do wear chemical resistant gloves when working on this stuff!

[camcruiser13]

so i tried this and it ate through my bar stock that i had in the water connecting to the poss. cable, just testing the waters, i did it on a ramshorn header and wasnt impressed, im sure i did it all wrong.

[vtcruiser60]

I read this thread in the winter and have been eager to try it out. My son and I had some time yesterday and gathered the parts. Honestly the most difficult thing was finding the laundry wash. We tried three stores, then went home and started phoning around. The sixth store had the product for $2.39

It works really well on a small scale as the pictures show. The bubbles give you immediate feedback that it is working. In the end, my smog pump bracket looks like it came right out of the cast mold. Anyway...I am adding some quick pictures so folks can see one type of set up. It is really easy....and a lot easier to do than setting up a makeshift sandblast cabinet...easier on the ears...clean up...etc.

[Coolerman]

For those trying this without success: Some new electronically controlled chargers will NOT work for this application. The chargers think there is something wrong with the 'battery, IE your part' and will refuse to put out any current. To trick the charger into working hook the charger correctly to a good battery (+ to + - to -). Now connect your part to the battery using jumper cables watching your polarity. + to sacrificial part and - to good part being cleaned. The charger will now see the battery AND the part as a single circuit and try to 'charge' them both. This does reduce the amount of current to the part but it only takes milliamperes to de-rust a part. Too much current and all you are doing is creating excess gas. Like you need any help there!

Read on my site about what the gas can do if you get too curious with a flame near the tank!

[FLFJ40]

I thought this was some kind of wives tale, but it was to intresting not to try it. Especially when all I had to lose was some laudry "soap" that I could use on my greasy clothes anyway. This is by far the BEST way to clean small parts. I have tried wire wheels, sandblasting, rust converting liquids. Nothing works like this.

[joeyg1973]

You can get sodium carbonate at you local pool supply store. You can use baking soda as well or anything that will make the water conduct an electric current. I actually learned about this method when I stumbled upon the stove bolt web page. I have actually switched to the vinegar method for most of my stuff. I keep the electrolysis method for the really large gross parts.

Stovebolt Page Tech Tips -- Good advice for owners of antique Chevrolet and GMC trucks

Joe

[TOBASH]

Most of the parts I have that are rusted get an acid bath, a wash, a blast with WD40, and a trip to the oven to get rid of latent water and theoretical hydrogen in the steel.

What is the advantage of this over muriatic (plumber's)acid given most of the rust in the washing soda method is just converted to another type of rust and not usable metal?

[Coolerman]

Well first, it's a lot safer than a big vat of acid. Especially if you have pets or kids.

Second, no method of rust removal converts rust to 'usable metal'.

Third, it's cheaper. Water = free, a container of sodium carbonate that will last you years = #8.00 around here, a 33 gallon plastic trash can from Wal-Mart = $7.99, and most folks have a battery charger and a bunch of scrap steel laying around if they own a Cruiser.

The acid works great though. I have done many nuts and bolts in muratic to quickly clean them...

[TOBASH]

Muriatic is cheap as dirt, but it is dangerous, especially to inhale.

Thanks, and best,

T