# Electrolytic derusting my experience (wip)



## seaco

I have read a fair bit about this now and thought that looks like a good idea to me and now I've done it I found it easy to make and from the limited results I have so far a real success!

Here's what I did...

This is the start I had some threaded bar I used a piece in each corner and a plastic tub of some sort...







Fit a rod in each corner, I had some little brackets, I used self tappers to hold them in place...







Like this...







Jumped ahead a little here, all I did was joined wire to each rod to make a loop with washers and nuts then used another piece of rod drill through the middle top of the tub... Then all you need is normal washing soda I bought mine in Tesco for 59p and water I used about half a cup for that amount it allows the current to flow through the water, one other thing Small amounts of hydrogen are emitted in the electrolysis process. Good ventilation or an outdoor work site is all that is needed....






I bought this from a car boot for £2 it's a 12v transformer for a train set but a car battery charger seems to be the usual thing to use...






This is the first sacrifice I found for derusting...






*READ CAREFULLY THE POLARITY IS VERY IMPORTANT *You connect the live wire to to the outer rods and the negative wire to the centre rod, then I used thin wire to suspend the different pieces, here's the allen key just don't let the outer rods come into contact with the suspended tool etc. even with it switched on I found I could move the tools under the water without feeling anything after all it's only 12v...






Here's a few other bits also... the parts actually start fizzing and if it's quite you can actually hear it...






I don't make out to know how this works but this is all the rust being collected from the tools...






After about 2 hours... Just look at the crud that's accumilated! also the good thing is when the water is to cruddy to use you can literally throw it down the drain or on the garden as there's no harmful chemicals produced...






This is the result 3 hours later all I've done is wipe it over with a paper towel...  






I'm a very happy bunny... The good thing is you can't over do it, obviously thicker rust takes longer and I've heard you can leave it for 48hrs or more, all you need to do when it's done is thoroughly dry it and protect it... 

Give it a go!


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## Green

That is excellent.


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## mrbingley

Seaco,
A very interesting project.  

Chris.


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## andrewm

Lee,

Do you really need such thick cables for the supply? The current flowing in the thin wires which you are hanging the pieces from should be the same as the current flowing from the supply. If it is not enough to melt the thin wire then the thick cable is probably overkill unless you are using very long lengths and need to minimise voltage drops.

Andrew


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## tnimble

Excellent job on making your own de-rusting unit!

@andrewm: The wires do not need to that big. But using thicker wire then absolutely necessary reduces resistance between the anodes. The lower this resistance the more balanced the de-rusting will be.


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## DeltaCharlieGolf

This maybe a stupid question, but will it work for aluminiumn composites?


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## seaco

DeltaCharlieGolf":g3d7ux2z said:


> This maybe a stupid question, but will it work for aluminiumn composites?




Sorry I have no idea but I doubt it...


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## Tom K

Way cool! Lots of plastic containers should be being emptied of lady tut and secreted in members workshops over the next few days. I just need to check she has one large enough for a No7 :lol: 

Cheers Tom


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## LarryS.

I never use the word 'cool' out of principle. But I have to agree with Tommo, that is way cool !


now just got to find something rusty


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## seaco

Tommo the sawdust maker":3q9lwzir said:


> Way cool! Lots of plastic containers should be being emptied of lady tut and secreted in members workshops over the next few days. I just need to check she has one large enough for a No7 :lol:
> 
> Cheers Tom



Hi Tom

If you are serious about doing a No7 then just remember that this system works from inside out so if you have any rust under your original finish it will force it's way though and push off the paint it's a bit unforgiving this way but is brilliant at getting the rust off...


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## bluezephyr

Ive heard about homemade ones before, But never really looked into how to make one, Ive been told theyre fansatic for cleaning old motorbike carbs.
If i can remember, Different solutions for different metals?


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## Digit

Seems a bit risky to me. The way I clean carbs is, (don't tell the wife) the dishwasher!

Roy.


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## bob_c

Ive always used citric acid in the bath with a small amount of table salt.


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## Tom K

LarryS":3eqf6ucs said:


> I never use the word 'cool' out of principle. But I have to agree with Tommo, that is way cool !
> 
> 
> now just got to find something rusty



Man when I tell you she was cool, she was red hot
I mean she was steaming

Its a question of when you were miss-spending your youth I guess could be worse I remember thinking stuff was groovy too :lol: 

Regards Tom


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## brianhabby

Digit":cr3tui4h said:


> Seems a bit risky to me. The way I clean carbs is, (don't tell the wife) the dishwasher!
> 
> Roy.



Dishwasher sounds even riskier to me, especially when she finds out :lol: :lol: 

regards

Brian


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## DaveL

Digit":anc7g0ju said:


> Seems a bit risky to me. The way I clean carbs is, (don't tell the wife) the dishwasher!


I pop my ceramic stones in the dishwasher when they get a bit cloged, brings then up lovely.  

That's the benefit of loading the machine before going to bed and being the first up in the morning. :-$


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## Digit

I hadn't thought of that! Good idea.

Roy.


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## TheTiddles

DaveL":2bcre1qp said:


> Digit":2bcre1qp said:
> 
> 
> 
> Seems a bit risky to me. The way I clean carbs is, (don't tell the wife) the dishwasher!
> 
> 
> 
> I pop my ceramic stones in the dishwasher when they get a bit cloged, brings then up lovely.
> 
> That's the benefit of loading the machine before going to bed and being the first up in the morning. :-$
Click to expand...


See, 'significant other' never bothers if I do things like that, probably because it's always me that does the cleaning...


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## martin.j.h

Whilst making mixture to ebonise some oak I put rusty nails in some white vinegar. a week later and the rust had gone! (just like Cillit Bang..or what ever its called) and the nails were shiny as new. Not what I wanted but I thought I'd add it to the post.


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## hgporter

DeltaCharlieGolf":3fhhcgdv said:


> This maybe a stupid question, but will it work for aluminiumn composites?



No. Iron oxide only.


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## Green

Hi

A few questions:

1. Does this only work with DC current?

2. What are the minimum/maximum voltages?

Just trying to make sure I have this right before proceeding as I think electricity is the work of the devil.

Cheers


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## Digit

> I think electricity is the work of the devil.



Thank God! No more stoking! :lol: 

Roy.


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## punkrockdad

theres loads of information on google. the only thing i noticed after reading a few of them is not to use stainless steel as the positive. it can create poisonous gases and the electrolyte is also then considered a hazardous waste. but one chap did recommended it as it didnt rust!! I suppose the lesson here is to read as many different accounts / methods as possible.

I've recently used it to clean up an old bench vice. Came up lovely!! One thing I did learn was that it appears to work on 'line of sight'. ie 4 large plates of steel surrounding the object tended to work better than one bar in the corner.

Another warning sign of introducing different types of metals into solution is the colour of the debris. It should only be orange / brown. Any other colours I'd tend to be wary.


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## Green

Thanks Punkrockdad.

I had read a few guides and was lead to believe that stainless was a good idea. Thanks for the advice, I will look around for some old iron instead.


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## maltrout512

You say that after a while you can dispose of down drain or in garden. Now not being a nerd I use this method for cleaning coins and artifacts that I find while out metal detecting, and when touching the cleaned objects that have been in the solution _*always*_ wash hands well afterwards. You use in a well ventilated area because of the harmfull gases given off. Now if there are harmfull gases being given off then the solution will be harmfull. So care should be taken at all times. Been there done it and even got the shirt as well.


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## George_N

maltrout512":2caghx8z said:


> You say that after a while you can dispose of down drain or in garden. Now not being a nerd I use this method for cleaning coins and artifacts that I find while out metal detecting, and when touching the cleaned objects that have been in the solution _*always*_ wash hands well afterwards. You use in a well ventilated area because of the harmfull gases given off. Now if there are harmfull gases being given off then the solution will be harmfull. So care should be taken at all times. Been there done it and even got the shirt as well.



The vast majority of the gases being evolved at the electrodes will be hydrogen and oxygen from the electrolytic breakdown of water. This is a highly flammable and potentially explosive mixture so that is why good ventilation is essential.


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## Dibs-h

Digit":32ib05xz said:


> Seems a bit risky to me. The way I clean carbs is, (don't tell the wife) the dishwasher!
> 
> Roy.



Daz non-bio is fantastic for cleaning gunk off engine parts - :-$


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## jefword

Hi, 
Sorry to resurrect this old thread but I found it through Google and joined your forum for a bit of advice on this subject.

I have recently been given my fathers WW2 Royal Marine Commando Knife, It's a Fairbairn Sykes MK 2 with a knurled brass handle and is very rusty.

I have left it in an oil bath for a week and scraped it with a flattened copper pipe so as not to damage the steel but without much success.

I do not wish to take it apart as this will damage the top nut and would then not be original. 

If I was to suspend it in an electrolytic bath as described, would this damage the brass.

If so, what if the knife was only dipped to the hilt leaving the brass out of the solution, would that be ok.

Thanks in advance for any help.


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## Cottonwood

You could use a wax resist to prevent the electrolyte from touching the brass of the handle. I used that technique frequently when I worked in a plating factory doing hard chrome finishes on the inside of cylinders but leaving the outside unplated. Simply coat the handle and finger guard (ie everything but the exposed blade) with wax, eg dipped into a pan of molten wax or painted on then suspend in a vat as mentioned earlier in the thread. I never knew chromic acid to affect the wax, not sure what would happen after immersion in washing soda. But the elctrolysis process will ruin exposed brass, its only for ferrous items


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## MMUK

Green":38rlpmu4 said:


> 1. Does this only work with DC current?
> 
> 2. What are the minimum/maximum voltages?




I know this thread is 5 years old but seeing as no-one answered this.....

1. Electrolytic derusting and electroplating (same principle as derusting but the electrodes are connected the opposite way round) will only work with direct current. The current must flow only in one direction to pull the rust away from the work piece.

2. The voltage of your power supply isn't too important as you are limited to the redox potential of the metals you are using. What is more important is to have a decent current output.

Also, for faster electrolysis, use flat plates with a larger surface area instead of allthread.

HTH :mrgreen: 


BTW, electrolysis won't clean fuel deposits from carbs.


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## Harbo

You could try other methods like Phosphoric acid or the Shield Technology chemicals that Workshop Heaven sell.
The latter will not damage brass.

Rod


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## jefword

Hi, Thanks for your advice. I think I will try the Shield Technology rust remover first.
Will let you all know of the result.
Thanks again.


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## Harbo

The Gel works quite well on small stuff as you apply to the surfaces you need to work on only. And quite easy to redo if not all rust removed.
I think it brings up brass nicely too - but check?
























Rod


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## Rhossydd

Impressive Rod,

Is that the finish straight after the gel or did you have to do anything else ?


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## Harbo

That's the liquid but I've used the gel on other things and it worked just as well ( no photos though).

Rod


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## andersonec

DeltaCharlieGolf":26ndctnc said:


> This maybe a stupid question, but will it work for aluminiumn composites?



No, steel only. 
Also, make sure you do not use stainless steel for your rods.

Andy


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## tool-me-up

Done this a few times myself, Normal table salt also works well as the electrolyte - the more you add the stronger the electrolyte and the better the current is passed.

For a tub of that size I would be looking to DISSOLVE 2 to 3 of the large tubs of table salt ( you can heat the water first to help it dissolve )

I use a PC power pack around 600w with both the 12V and 5V rails connected to the electrodes 
guide here
http://www.instructables.com/id/Converting-a-computer-ATX-power-supply-to-a-really/

You can also use this method to "acid etch" metals, by waterproofing the parts you dont want etched in waterproof tape or similar.

See here for a demo http://www.instructables.com/id/How-To- ... ctro-Etch/


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## John Brown

> both the +12V and +5V rails connected to the electrodes


Do you mean the same electrodes? If so, how does that work?


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## tool-me-up

John Brown":3lgr9mnb said:


> both the +12V and +5V rails connected to the electrodes
> 
> 
> 
> Do you mean the same electrodes? If so, how does that work?
Click to expand...

pretty sure both to same electrode - the way a powerpack for an ATX pc works will then give you 17volts if you connect both the red and yellow wires - just make sure to use both black wires for the earth.

It was a while ago so here is the guide for yourself
http://www.instructables.com/id/Converting-a-computer-ATX-power-supply-to-a-really/


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## tool-me-up

John Brown":197dvcti said:


> both the +12V and +5V rails connected to the electrodes
> 
> 
> 
> Do you mean the same electrodes? If so, how does that work?
Click to expand...


It was a while ago so here is the guide for yourself
http://www.instructables.com/id/Converting-a-computer-ATX-power-supply-to-a-really/

I've edited previous posts because I cant remember exactly how I did it so follow the guide for yourselves - I did get it working though and was out putting 17v checked with a multimeter


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## John Brown

I would suggest that anybody hoping to to use a PC power supply for this sort of purpose should:
a) Read the linked article - it is not a matter of connecting the red and yellow wires together, in fact I would strongly advise against that.
b) Be aware that the negative voltages available from a PC PSU can not deliver anything like the same current as the positive ones, and that the putative 17 volts will be limited to the lower current capability of the -5V supply.


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## tool-me-up

John Brown":1j8rgco2 said:


> I would suggest that anybody hoping to to use a PC power supply for this sort of purpose should:
> a) Read the linked article - it is not a matter of connecting the red and yellow wires together, in fact I would strongly advise against that.
> b) Be aware that the negative voltages available from a PC PSU can not deliver anything like the same current as the positive ones, and that the putative 17 volts will be limited to the lower current capability of the -5V supply.



I had it working but thats going back a couple of years - I definitely got 17 volts from the power pack - but I remember it taking a bit of fiddling. As I said in previous post - I THOUGHT it may be the red and yellow that supply the molex connectors but im not that sure now ive sat and thought about it.

I have a spare psu somewhere and when i get chance ill lend a mulitimeter and try it again.

ATB

Gav


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## MMUK

tool-me-up":1v4ur4p0 said:


> John Brown":1v4ur4p0 said:
> 
> 
> 
> I would suggest that anybody hoping to to use a PC power supply for this sort of purpose should:
> a) Read the linked article - it is not a matter of connecting the red and yellow wires together, in fact I would strongly advise against that.
> b) Be aware that the negative voltages available from a PC PSU can not deliver anything like the same current as the positive ones, and that the putative 17 volts will be limited to the lower current capability of the -5V supply.
> 
> 
> 
> 
> I had it working but thats going back a couple of years - I definitely got 17 volts from the power pack - but I remember it taking a bit of fiddling. As I said in previous post - I THOUGHT it may be the red and yellow that supply the molex connectors but im not that sure now ive sat and thought about it.
> 
> I have a spare psu somewhere and when i get chance ill lend a mulitimeter and try it again.
> 
> ATB
> 
> Gav
Click to expand...


You won't have any trouble getting the 17 volts but the actual current will be restricted by the negative (earth) line on the 5v side as John said.

It's the current you need to measure. You'll find using a PC PSU that you'll get a larger current just using the 12v on it's own as the -12v rail allows more current flow back than the -5v rail.


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## tool-me-up

I see, I misread your post, sorry John. Yes the 5v rail has a lower wattage rating than the 12v rail. It should be stated on the side of the powerpack

I think I had mine like that for etching more than anything else, which didnt require as much amps as I wanted the process to be slow and gradual.

For rust removal I found a laptop charger provided a lot more wattage as it was 24v and around 5 amps i think


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