Restoration Tip: Electrolysis Derusting

[Mark Sierant]

Built a Soda bath the other day and decided that the more more power you put in the quicker the job will be done and placed a filthy weapons carrier bellhousing in the tank. I have acces to large deep cycle batteries as used in telephone exchanges so I built a string that could deliver 48 volts and 100 amps. Well all went well at first it took about one minute for my 60 litre tank to look like a foaming cup of coffee. I left it to run for about 1 hour when I returned the water had dropped two inches and was close to the boil. At this point I decided to pull the plug on my experiment. Silly me I removed the negative from the work only to be thrown a couple of metres in a bright flash and huge bang. As I removed the lead it drew a large arc igniting the Hydrogen being given off by the soda brew. It was well ventilated but I was still producing enough gas for a good blast. I think in future I will reserve this sort of power input to a 1200 litre tank I intend to buy.


BE CAREFULL RESTORERS

[Snowtractor]

...as HOMER would say, hope you're alright and still have all your hair.
Watched discovery channel last night and there was a blurb on Hydrogen. It said it had 100 TIMES MORE ENERGY than gasoline. They filled up 2 party sized ballons , one with straight oxygen and the other with hydrogen. Then they used a very long pole ,with a match on it, to light the ballons. The O2 went bang, neat , the H went "BOOM" and shook the camera about 30 feet away. Impressive, and dangerous, more so if in a confined area.
Sean

[Alex Blair (RIP)]

Mark...
Sean probably has lots of experience about explosive gasses and would be the first to comment on your story...
Probably could tell a story or two on explosive liquids of the 100 proof ,homemade variety....
Anyway ,how did the bell housing turn out..??

[Snowtractor]

Originally posted by Alex Blair
Mark...
Sean probably has lots of experience about explosive gasses and would be the first to comment on your story...
Probably could tell a story or two on explosive liquids of the 100 proof ,homemade variety....
Anyway ,how did the bell housing turn out..??

Easy there big fella, you being from Ottawa " land of the hot gases" I think I stand in good stead.
Sean

ps: hiccup

[Bob Moseley (RIP)]

To Mark and All Restorers,

Remember the fable of the Tortoise and the Hare.

The golden rule I always impart to my team of restorers is "these vehicles are 60 years plus old, work at their speed". I would rather have someone take days to remove a rusty stud than have it shear off and then spend the next few days drilling and tapping to replace it.

Mark, you were very lucky.

Bob

[Max Hedges]

Sounds like a bit of Russel coming out in you again, old mate. l did hear of one bloke put a big dint in his shed door in town.

Max

[cmperry4]

I was reviewing this thread with an eye to setting up an electrolysis rig and figured Arm&Hammer Washing Soda is the most likely and readily available product hereabouts.

Here's a link that lists all a whole lotta N.American household products that use sodium carbonate:

http://householdproducts.nlm.nih.gov...tbl=chem&id=16

I don't see that CLR stuff they're always trumpeting on TV - I got some to clean the rust stains in the toilet - expensive. Haven't tried it yet.

Note that the Arm&Hammer is >= 86% concentration, but that Prestone cooling system cleaner is 90-98% (along with some other potent ingredients)

I also have some of that commericial grade caustic soda stuff for cleaning coffee pots - it does brilliant job on my coffee thermos - but nasty to use, fine powder goes aerosol when disturbed, not nice to breathe. It would probably be great for rust removal, too.

[cmperry4]

If any Canadians are planning to set up for electrolysis, nip over to your Canadian Tire store and look for a nifty 75-litre (about 20 gals) heavy plastic round tub with rope handles they have on for a whole $9.99 - at least here in Winnipeg they did - I picked one up the other day (along with some Arm&Hammer washing soda) and figure it should do nicely. It's a little over knee-high and about 2 feet across at the top.

[Lynn Eades]

I'm no expert here but on hydrogen embrittlement, If you have an item that has been chrome plated , and you re chrome it you will severely weaken it as the process brings hydrogen to the surface of the metal which weakens the metal just as bringing nitrogen to the surface toughens it as in "nitriding"- dont re-chrome structural stuff like suspension/steering components.
Phosphoric acid is a food preservative. it is very good for cleaning ferrous metal (steel) Its probably the active agent in the HPsauce. If your going to use it talk to an industrial chemist first.
In an Impco book I read an article about how important it is to have good heat transfer from an engine block to the coolant, direct rather than through a layer of rust scale. The article reccomended cleaning the engine block out with muriatic acid, Which I understand is a particular strength of phosphoric acid to which an inhibitor is added to stop the acid continuing, once it has broken down the scale. I found it worked very well.
If you set up an acid bath with phosphoric, dont put cast iron or high carbon steel in it or every thing you put through it after that comes out black.
The great thing about any of the methods used in this thread is that they chemically stop the oxidation process whereas the purely mechanically process of blasting doesn't.
My carrier with its particular type of steel floor was quite rusty, the blasting took hours and hours because each little rust hole seemed to turn into a rust cavern inside, and although it was painted straight away the rust has re appeared. Because this has proven to happen quite a bit, I now like to combine mehanical and chemical cleaning. ....A great thread, Thanks guys.

[Bob Moseley (RIP)]

Hi all
As this thread has again been visited I thought I would have another look over it myself. I'm very pleased and proud of all the responses since it began in February 2003 and through our illustrious Spinning Ball, it created the Restoration Forum. Keep the tips coming.
Bob

[cmperry4]

Got my 20gal/75 L tub full of water, got a nice clean steel rod (from an old stair runner, I think), mixed it up, hooked it up and works like a charm. Rust sloughed off an old battery tray like algae after an overnight session.

But here's the question: I bought a box of Arm&Hammer washing soda, which is 3 kg, or 6.6 lbs. According to Bob, he uses 1 lb/450 ml of soda to 4.5 litres (i.e. 1 gallon) of water, which in my tub would require 7.6 kg or 20 lbs of soda. Another online source http://www.bhi.co.uk/hints/rust.htm says 1 tablespoon soda per gallon, which for 20 gals, would be about a cup and a half. I dumped in the whole 3 kg box, thinking it wouldn't be enough, but it seems like more than plenty- the reaction just fizzes away nicely.

Update: This with a 12V, 10-amp trickle charger, which is indicating 3-4 amps as it works.

So does anyone have the definitive proportions of soda to water? Or is it like martinis, mix to taste?

[SteveJ]

Hi this is a great thread. I am going to try the electrolysis method.
I used myriatic acid soloution to clean an M38A1 fuel tank. It ate the rust instantly (wear a mask and goggles) and discovered every pinhole or potential pinhole in the tank. After a good soaking (15 min) I flushed it out with copious ammounts of water and sloshed it out with methyl hydrate. I repaired the pinholes and the tank is working great to this day.

Just a note on phosphoric acid, I used to work in a chemical fertilizer plant many years ago and this acid was used to make the fertilizer. Nothing rusted. The acid tended to solidify into a kind of muck and if you left your shovel stuck halfway in it for a couple of days and then gave the handle a pull the blade would snap off clean at the level of the acid mud. It really embrittled the steel.

SteveJ
43 GPW
52 M38CDN W/W
53 M100 CDN

[greg anderson (RIP)]

Can someone kindly point me to the discussion which I believe was on this site concerning the removal of rust by electrolysis using baking soda?--molasses etc.- thanks

[grant fincher]

Look back to a thread started by Bob Mosely on the 17th of August this year. I'm sure you will get the information you need as there is 2 pages of different methods listed.
Good Luck

[Barry Churcher]

Greg, you can give this site a look also.
Cheers,
Barry

http://www.stovebolt.com/techtips/ru..._derusting.htm

[greg anderson (RIP)]

Thank you both

[Jordan Baker]

HI Greg

Here is my setup that I used very succesfully during the summer. I got a large plastic container at CDN tire along with the battery charger. This charger has both 6/12 volt charging and 100amp boosting assist. I also got a product from the super market called "Washing Soda" Stewart Loy put me onto this stuff. I think it cost about $6 for the box.

Anyway I hooked up fence wire leads running to all the metal anodes. This has the red battery clamp going to it. The other piece of wire was clipped to the black clamp. On some parts i just clamped the black hookup directly to it.

Fill up the container with water and add a couple of handfulls of the washing soda. Stir it all up. Hook the part you want cleaned and submerge it into the water. make sure you have hooked the part to be cleaned up to the negative terminal. Don't let it touch any of the anodes either. Turn on the battery charger and let it do its thing. I found that having it on the 100amp boosting setting worked the best and the fastest. Also you need really good conections on your hookups.

This first photo shows my setup. I did this away from any buildings just in case I messed up.

[Jordan Baker]

Here is one of the carrier parts that I cleaned with it. It had a really bad case of surface rust and a bit of peeling paint. This picture shows that part immediatly after coming out of the electrolytic process. It actualy removed most of the rust and the green paint. The grey paint was the primer that was underneath. I gave it a quick scrubb with a wire bush and then washed it off with the hose.

[Jordan Baker]

Here is the part all washed off and dried ready to be painted.

[Bob Moseley (RIP)]

Hi Greg
This is THE thread. There have been many responses and it contains everything to be known about this method.

Mr. Moderator - would it be more appropriate to rename this thread "Electrolysis Derusting" as opposed to the generic name it bears at the moment?

Bob

nice work Jordan , i use a friends small porable sand blaster for mine, he did all his small parts for his WC 52 witch came out great , i still use a electric hand sander when i want a quike job.


BIG MIKE

[Lynn Eades]

It should only be used for mild steel. nothing else!

[Hanno Spoelstra]

Originally posted by Bob Moseley
This is THE thread. There have been many responses and it contains everything to be known about this method.

Mr. Moderator - would it be more appropriate to rename this thread "Electrolysis Derusting" as opposed to the generic name it bears at the moment?

Edit: both threads merged and renamed.

H.

[Bob Moseley (RIP)]

Thanks Hanno
The thread makes much more sense now and I've certainly learnt a lot more about this topic since others have responded.
Bob

LYNN ARE YOU A BROAD?LOL



THE EVIL ONE

[tankdriver]

Shouldn't this be a sticky?.....

This has some really great info......

Also did anyone very find an answer to cmperry4 question about the weither the amount is one pound, or one 1 tablespoon soda per gallon?

Thanks

[jim sewell]

Approx one table spoon per gallon

Regards
Jim S.

[tankdriver]

Thanks

[cmperry4]

Then I used waaaay too much.

[tankdriver]

Did it work better?