How could I fiddle with old, rusty Z's for 15 years and not know about Electrolytic Rust Removal? Someone else mentioned it here, I Googled it and studied these articles:

Electrolytic Rust Removal

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

http://www.buchanan1.net/rust.shtml

Electrolysis Rust Removal

http://www.htpaa.org.au/article-electro.php

The process was cheap, didn't require any nasty chemicals, didn't produce any nasty chemicals, and seemed to produce good results, and since I have no shortage of old rusty Z parts lying around, I decided to give it a try.

I went to the grocery store and bought a box of washing powder, which is simply sodium carbonate. Some of the sites say you can use baking soda (sodium bicarbonate) but I didn't find any articles where anyone had tried it. Basically, all the sodium carbonate does is make the water conduct electricity better. Then I bought a sheet of 22 gauge steel from the hardware store (it must NOT be galvanized/zinc coated). Some people use rebar. Don't spend a lot of money on your electrode--it will eventually get eaten away in this process. Also you don't want to use stainless steel because it can create hazardous insoluble hydroxides or oxides. I filled a 5-gallon bucket with water and pulled out the battery charger. Then I selected a nicely rusted brake rotor.

I put roughtly 5 tablespoons of washing powder in the bucket and stirred it up. I bent the steel sheet to fit the curve of the bucket and inserted it so that a few inches stuck out above the water. I put the rotor in the bucket so that it was a couple of inches away from the steel sheet. The rotor just barely fit in the bucket, so I was sure it wasn't going to move. Later I clamped the steel sheet to the side of the bucket.

I moved all of this outside to the garage stoop. You want to do this in a well ventilated area because this process is going to release pure oxygen and hydrogen. Don't smoke around this! I left the battery charger just inside the garage door and stretched the leads outside so I could hook the battery clamps up to the rotor and the steel sheet.

I checked the article once more before I switched on the charger...GOOD THING! Did you catch what is wrong in the picture above? I reversed the wires! You want to put the NEGATIVE terminal on the rusty piece and the POSITIVE terminal on the steel sheet or electrode. If I had left it this way for very long, my positive battery charger clamp would have gotten eaten away. You want your rusty piece to be submerged in the water and it's ok if your (negative) charger clamp is partially submerged. You don't want your positive charger clamp on your electrode (steel sheet) to be under the water.

I put the charger on 6V and plugged her in. Immediately it showed a 2 amp draw. In just a minute bubbles started rising off of the rotor and the steel sheet. The bubbles coming off the rotor are hydrogen and the bubbles coming off the electrode are oxygen.

I left it outside overnight. When I checked it in the morning the water had turned rust-colored and had rust-colored foam on top. I unplugged the charger and unclamped the leads.

I looked at the steel sheet. It was covered with thick black stuff--oxide. I pulled out the brake drum, hosed it off and scrubbed it with a plastic brush. Then I dried it off with a paint dryer. Sure enough, the rust was almost completely gone! Almost, but not completely. So I pulled out my drill/wire disc and worked on it. It didn't take much effort at all to make it shine. Now, it looked a lot better!

It still looks a little darker than you'd expect brand new steel to look. I think part of that is from oxidation in the process. The amazing thing is that it seems like every flaw in the rotor now stands out like a sore thumb.

My now-rust-free rotor is now extremely rust-prone so I applied some Sherwin Williams Ultra Clean and later I might shoot some WD40 on it.

My rotor is rust-free on only one side. This process only removes rust for the parts of the rotor that could "see" the steel sheet. This is because the electrons take a direct path from the electrode to surface of the rusty piece. I'll have to turn the rotor over and treat the other side.

Overall, I'm pretty pleased with this process and I'll use it on as many parts as I can. I want to do some more research before applying this to stressed parts like suspension pieces. I've read that this process can cause hydrogen embrittlement--some of the hydrogen goes into the metal. It's possible that the hydrogen can be released by baking the piece afterwards for a few hours in a 200-degree oven, but don't take my word for that. And I'm assuming you don't want to even think about doing this for internal engine parts.

Next, I have an incredibly rusty oil pan I'm going to treat. Also, I'm going to figure out how to set up the old plastic kiddie pool to de-rust larger parts.

And if I can just figure out who will let me drive my stripped chassis into their swimming pool and how much washing soda it would take to treat my entire car...

26th,

Thank you for sharing what you are doing/ going to your body shell. I read this with great interest, and look forward to reading any full article/thread.

Cheers

Ian

Okay, I've tried this process twice and failed both times.

The first time I used a battery charger that was too smart for its own good. It threw an error code that said the battery was too far dead to be charged. I was trying to use 2 amps and it was a 12-volt charger.

So I bought a simpler charger designed for smaller batteries. It is a 6 or 12 volt (you can select which) and 1.5 amps. This charger has three lights that indicate what it is up to: "Charging," "Charged," and "Trouble." Well about five minutes after I start it up it will switch over to "Trouble" and quit sending current.

Can anyone recommend a charger or other power source that will just send current without asking questions?

Can anyone recommend a charger or other power source that will just send current without asking questions?

I tested this process recently with a cheap trickle charger that doesn't have any of the fancy settings like yours do. You could probably even use your car battery itself. You could use jumper cables to the project and then hook up the charger to keep the battery charged.

Another option would be to use a standard 12-volt power supply. I have no experience with the following products but it came from a Google search and will at least let you know what I'm talking about:

http://www.baproducts.com/pyramid.htm

Here's something similar from Radio Shack:

http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CTLG%5F009%5F001%5F005%5F000&product%5Fid=22%2D507

I just used a basic 12V charger that was rated at 10 amp.

There will about 1 to 3 amps of charging current at the start

and rising to about 4 or 5 amps. You could use a car battery

and the charger to keep it charged. But put a head light in

series between the battery and the electrode so a dead short

will just make the light bright. The light will glow as this

contraption is working

I did mine a little different but still the same results.

I used a garage sale stainless steel sink.

http://67.42.8.86:8884/Files/Datsun/Rust/

After a a few days the sink gave up and I cut it up

and used the plastic bucket with what was left of the

sink for the + electrode

Dave,

The solution they are using in Wauchula is Sodium Gluconate, Sodium Hydroxide, and Sodium Cyanide. They use copper plate for the annode. The plate covers the entire tank.

26th-Z is back home in Sarasota. We found her a nice air-conditioned body shop for me to grind welds. Just spent the whole afternoon grinding welds. Nicked my fingers a good one or two!

Did you notice any outgassing? I'd like to do mine indoors, and don't care for any explosion hazard.

thx

I did finally build myself a de-rusting setup, and it really works!

I used a steel bolt as the anode, but I didn't have any copper wire for the connections. I put it all in an empty 1 gal windsheild washer fluid bottle which had the top half cut off & some notches for a cross-support. I found a 12V power adapter to use for the power supply, and hooked it all up to de-rust some heater hose holders. The 150mA power dapter was enough to do the small part.

The only thing I had a problem with was the black stuff left on the part after de-rusting. What have others done to remove the black stuff and get the part shiney- or clean- looking?

thxZ

Successs on an engine block!

I helped a professional Rolls-Royce restorer guy de-rust an engine block using the electrolytic method. We used a big plastic 50-gallon drum for the container, rested the engine block on wood blocks on the bottom, and used 8 rods of rebar around the perimeter as the electrodes. the rods were flattened on the ends with holes drilled for screws for the best electrical connections. 12 ga. stranded wire with eye-connectors were used all-around (there was a big roll handy.) The power was a 20 Amp, 6-volt battery charger; 12 volts didn't look to make any difference. Current was about 17 amps to start, and smoothed out to about 10 Amps at the end.

The process took about 20 hours total.

There was probably a good inch or so is rusty crud floating on top,which was scooped off with a paper cup and the electrodes were barely affected.

The block was finished off with water to flush the cooling passages, and a rinse with some light scrubbing to get the black oxide coating off, and the bare metal was protected with a spray-on waxy coating that resembled furniture polish. The waxy coating will be removed with solvent before painting the block.

The cylnder bores were examined before and after the process with NO CHANGES. The diameter was not affected, nor was the cross-hatching from the previous (original) honing. A light honing of the cylinder bores will be done anyway.

I think the total cost was about $50 -60 from the quantity of distilled water used, and the rebar rods. the rest was on-hand (plastic drum, wire, battery charger and washing powder.)

thxZ

Edited April 13, 200915 yr by TomoHawk