OutdoorKing Repair Forum Forums Restoring, Customising and Modifying Tech Talk Electrolysis Bath

Continued war on rust, I've been meaning to try this for some time now so off to the supermarket to get some washing soda, None, so Bi-carb baking soda it is, they are not the same thing but you can make Baking soda into washing soda by sticking it in a pot on high and stirring it every 10 min or so, I did this for a bit over an hour, once the sort of steam stops coming out of it it's done but I did it for a bit longer just to be on the safe side because it will not affect it any, set up a tub and some jumper leads and the battery charger and away she goes, working pretty fast too

the set up



the lid off my old Myers pump.



after 15 min



After 1 hour.



Will take some more pics when I get closer to finishing it, but I pulled it out for a look and it is working a treat.

Wow Jonesy, i've never tried it but have heard good things about it. i just didnt realise it was that easy to set up at home.
Is there a risk or leaving your parts in there too long and totally disintegrating them?

Rather than mucking about with Bicarb, you'd be better off getting some 'Soda Ash'.

Still a form of Sodium Carbonate, Na2CO3, but it's a bit stronger than Washing Soda. Washing Soda is about 15% water; Soda Ash is <1%.

Available from swimming pool supply shops, and larger farm/rural supplies, if there are any of those in your area. It'll work out cheaper too, as 10kg buckets and 1kg pouches are common pack sizes.



Just don't let anything made of aluminium alloy get in there; the bath is alkaline enough to corrode that quite quickly.

Bigted,as Gadge has pointed out, very good on steel and cast but will eat Aluminium and brass ect, the soda ash I will look into but I only used about $2 worth of baking soda and from what I have heard the water may get all gunged up but will last as long as you want to put up with it, I have also read that if you use Graphite or carbon for the sacraficial anodes the water stays clean.

one thing to note guys is dont use stainless steel as an anode. the end mixture is extremely toxic using stainless.stick to mild or cast steel for your anodes.

as far as disintegrating your parts. maybe if you left in in solution for 12 months?? it only reacts on the rusty bits so not too much to worry about

Nice result there Gizmo, as I am only new to this stuff I only know what i have read so you guys with experience can teach others the benifits and short falls.

Hi ODK Members,

Coming from an Electroplating background, What you have there is basically a caustic "Cleaner Bath" which in turn really needs to be heated just like a fish tank is but with a much bigger glass heater to a point where steam is coming from the surface. This process will also strip paint but Diecast metals should not be used as they have a Zinc content which caustic loves to eat. If used cold the process will slow right down and will take hours to perform opposed to minutes when hot.

As far as de-rusting is concerned the best method is to make up a Pickle Bath which again needs to be hot but requires no electricity at all as it is a "dip in solution only" type bath. Pickle baths are generally made up with 15% Sulfuric Acid and water but require the steel to be pickled to be totally oil free. This process is only good for Ferrous Metals and not "Die Cast" metals as they have a percentage of Zinc in them which sulfuric will attack instantly.

If you have any other electro/ chemical questions please feel free to ask as I'm only too happy to help out.

Cheers,
BB

BB I disagree with what you have said
You use washing soda or Soda Ash and no heat needed yes it can take a few hours for the above mower bass about 4hrs for me I have plenty of time
I have been using this method for about 20 years and lots of info on it
My tank set up below also lead is the best anode and you only need one
Ian


half Number plate took about 2 hrs then jet blasted with water and hand brushed with a brass wire brush

I decided to show how good a Electrolysis bath is
Electrolysis bath works by forming Hydrogen bubbles on the surface of the GOOD steel/iron which means everything paint/rust/grease etc is pushed of the surface of the good steel/iron by the bubbles. The wheel was put in overnight I usually do this ready for the next day

The wheel was not cleaned usually I brush of, jet blast of any lose junk
The wheel was NOT rotated over night as I was sound asleep




The wheel hanging in the tank with ONE anode facing the front of the wheel YES it was fully submerged



Removed from tank and you can see most of the junk has fallen off. What can be seen will wipe off with your fingers BUT to do a better job I use a jet blaster. Very small jobs where I would be chasing it around the yard with the jet blaster I do under a tap with a wire brush





All finished and clean when dry ready to paint or to make it shinny like the above mower base run a wire brush over it
Drying of for me in North Queensland with our hot sun is easy you might have to find another way or just use a wire brush before painting to get of rid on any new surface rust
Ian

Both of these methods are fine and correct... No right or wrongs, just different chemicals and minor process differences.

Ive used both methods as well as others.

BB's method has the advantage of fast time, ( good when your doing a job for a customer. Also the pickling process slows down rust reformation and etches metal...

Ian's method has ease of use, chemical costs should be lower too.

Both have similar labour content for prep and wash off.

Drawbacks for BB'S Method would be Safety with the hot process...Yes it burns! And as far as im aware we are no longer permitted to use hot caustic cleaning baths in the automotive industry.


For Ians method, Time, and the lack of a surface etch on bare steel causing surface rust, requiring more work to prep before paint.

Other effective cleaning methods are,

Cold caustic or alkaline bath... Slower than Ians Method and no etching.

hydrochloric Acid...Very effective, but to dangerous to heat, burns are severe and inhalation of fumes can be potentially lethal...Safer when diluted to 50% or below.

Phosphoric acid....Safer, slow process, must be fully emersed, slows surface rust as it etches metal.

Sandblasting....safe, easy, fairly quick and no surface rust. Cost can be expensive if setting up.

Bleach and molasses.....Very Very slow,days or weeks, but generally effective.

Liquid flux....cleans copper and brass in seconds

All processes listed cannot be used with aluminium alloys or diecasts as stated.

There are a few more methods requiring joint processes also.

Hydrochloic acid cannot be used on cast iron if repairs are to be carried out.

Both BB's and Ians methods are perfect for the uses they have stated, and very effective.

But most methods are good...If your set up to do them.

Very good for members to see how a process works effectively fellas!

For Ians method, Time, and the lack of a surface etch on bare steel causing surface rust, requiring more work to prep before paint
I don't do any more to it as long as I paint it with a etch primer as soon as it is dry and so far things that I have done many years ago have no rust coming through
COST
Washing soda I bought over 20 years ago for about $2 per Kg used 14kg = $28 Have added only 1kg since though it might need it but made no difference so there is no on going cost with chemical
The BIG plastic tank I got from the dump for $20
The battery changer from a grange sale $10
Power used all but nothing you are only using 12volts

BUT I think what is missing is what it can do
If you have a number of parts all rusted together put it in the Electrolysis bath with a wire to each part and you find it far easier to get it apart as the Electrolysis works on the inside or what you might say between parts that are rusted together
I used to do a number of old stationary engines (why the tank is so big)valves are stuck push rods stuck etc and instead of using all kinds of stuff you can soaked it in put it in the Electrolysis bath for 1 day and every thing comes apart

Here is something else people might be interested in
Of special interest to anyone who's Nuts about Bolts:
Penetrating Oils
Machinist's Workshop Mag recently published some information on various penetrating oils that I found very interesting. Some of you
might appreciate this.
The magazine reports they tested penetrates for break out torque on rusted nuts.
They are below, as forwarded by an ex-student and professional machinist.
They arranged a subjective test of all the popular penetrates with the
control being the torque required to remove the nut from a "scientifically rusted" environment.

*Penetrating oils .......... Average torque load to loosen
*No Oil used .................. 516 pounds
WD-40 ..................... ... 238 pounds
PB Blaster .................... 214 pounds
Liquid Wrench ..............127 pounds
Kano Kroil .................... 106 pounds

ATF*-Acetone mix..........53 pounds *ATF=Automatic Transmission
Fluid

The ATF-Acetone mix is a "home brew" mix of 50 - 50 automatic
transmission fluid and acetone. Note this "home brew" released bolts
better than any commercial product.

In this one particular test our local machinist group mixed up a batch and we all now use it with equally good results.
Note also that "Liquid Wrench" is almost as good as "Kroil" For about 20% of the price.

Yes I also have been using this process for many years as well.I use that cleaning soda (I think it's called) comes in a 1kg bag at woollies.Which is sodium carbonate and still have heaps left,and I bought the bag years ago.
Gizmo,I know it has been written not to use a stainless steel anode,but I have been using one for years and still have 98% of it in-tact.It has been used many many times over.
Also I have seen it written that it does work better in a controlled temperature,but from what I've been reading IanOZ the temperature of our water (Especially where you are) would be at that ideal temperature anyway.Besides that who wants the hassle of controlling the water temp?
Very interesting info there on the penetrating oil.
I know that ATF was good as I've always used that once WD-40 didn't work.Never thought of mixing it with Acetone.I think it's time to try that out.
Thanks IanOZ.

DANGEROUS TO USE STAINLESS STEEL AS THE ANODE. It gives off poisonous gas.
Other wise stainless works well
Heat has been mentioned a few times above
The method original came out of the UK and I know a number of people all over Australia
including where wots his name ??? lives that little funny island way down south
and nobody has said anything about heating up the water and I can't find where it might of been mentioned

This U-Tube is good the chap uses a scouring pad to clean under a tap YES I also have done that and when dry paint


These web sites don't mention heating the water
http://www.rickswoodshopcreations.com/miscellaneous/rust_removal.htm
http://myweb.tiscali.co.uk/andyspatch/rust.htm
http://www.familyhandyman.com/workshop/how-to-remove-rust-with-electrolysis/view-all
http://www.instructables.com/id/Electrolytic-Rust-Removal-aka-Magic/

Ian

Whats liquid flux?