tank rust removal

[Nipper]

This question has been done quite a few times on the forum previously ,but I need to get rid of the rust in a fuel tank. Has anyone ever tried having the tank dipped at an electroplater ?
I believe this "pickles" the steel of the inside of the tank. But not real sure of how effective it might be . Does anyone think it's worth the ten bucks to give it a try? Failing that I've got some molasses here in the shed that might be worth a try. Cheers.

[LWC82PE]

Just do it yourself with a 5L hydrochloric acid from Mitre 10. Its easy and thats all the platers use and you will be able to do a better job of it yourself. When i get tanks back from the chromers they need the insides cleaned out anyway.

[Nipper]

Cheers Leith  do I need to dilute the hydrochloric acid at all? or just " neat" into the tank?

[Rossvickicampbell]

it should already be diluted when bought from a "normal" shop.  Always remember though - acid to water - not water to acid!

[Nipper]

Thanks Ross, will do !

[Mick D]

Rossco is right in expressing caution for the use of acids.
It can be very dangerous and it is very unnecessary.

I have used diluted hydrochloric acid to clean up rust, available from building suppliers(Saddingtons Newcastle) sold to builders to dilute and pressure clean cement stains of new brickwork.
The out come can be totally FUBAR if you slip, fart, cough. sneeze or trip over when handling the raw concentrated acid.

As a kid I went through every single thing in my fathers shed, curious kids do that, make sure you keep it under lock and key.

There is a much safer way.
Since we are talking about steel tanks.
Oxidation(rust) is the loss of electrons due to the efforts of naturally occurring electrolysis that effects the molecular and atomic state of iron.
Simply encourage the process to reverse.

"Reverse electrolysis"
My panel beater friend Geoff showed me a couple of years ago.
My results are outstanding.
And I feel very safe and comfortable doing it.
My Electrolyte is just water with washing soda crystals, purchased very cheaply from Woolies Supermarket.
NET IMAGES


You wont even have to disturb the paintwork if the tank still holds fuel

[Colin Jay]

An alternative to hydrochloric acid is phosphoric acid.

Phosphoric acid is the acidic ingredient in molasses and Coke that gives these two products their rust eating capabilities. I was able to acquire a 20ltr drum of phosphoric acid many years ago (we used to use it for cleaning out 40mm gun barrels) and I have been using it ever since to de-rust the inside of steel fuel tanks with great success.

I don't know if phosphoric is commercially available in large quantities to normal consumers, but you could just keep pouring Coke into the tank and it will eventually dissolve the rust.

There is some evidence that long term exposure to phosphoric acid can cause low bone density / osteoporosis, so safety precautions are required.

CJ

[Mick D]

Ok, a shot of the sediment from my last clean up


I have played with it, results can be varied and improved easily.
So simple. I use my timber built outside Dunny for such things


I have to use a fan under the Battery charger to stop the thermal over load from switching in and out.
I have earth leakage and circuit breakers on my mains supply. This is also duplicated  on my workshop sub board. With a second earth stake as well, safety, to be sure to be sure. And most importantly, smoke detectors and a baby monitor beside my bed when I leave the process going at night.

I hate the damage done to frames etc when aggressively blasted.
My frames are soda blasted, no damage at all.

I purchased at auction a massive but very controllable truck, bus, earth-moving battery charging station.
And a giant size plastic wheelie bin.
Very soon, after a gentle soda blast my frames will be laser checked, straightened, Oven Jig relaxed, checked again and then all rust removed/reversed before being professionally painted, from a gun. Happy days.
Do it, you will be glad you did

[Mick D]

An alternative to hydrochloric acid is phosphoric acid.

Phosphoric acid is the acidic ingredient in molasses and Coke that gives these two products their rust eating capabilities. I was able to acquire a 20ltr drum of phosphoric acid many years ago (we used to use it for cleaning out 40mm gun barrels) and I have been using it ever since to de-rust the inside of steel fuel tanks with great success.

I don't know if phosphoric is commercially available in large quantities to normal consumers, but you could just keep pouring Coke into the tank and it will eventually dissolve the rust.

There is some evidence that long term exposure to phosphoric acid can cause low bone density / osteoporosis, so safety precautions are required.

CJ

Yes it is brilliant stuff Col.
I found five liters of it years ago when supervising the decommissioning of a plant.
Excellent for iron and aluminium. Brilliant for diluted use as a cleaner for Aluminium boats and repairs as such, etc.
The five liters lasted for an amazing amount of jobs.

I have tried and tried and tried to buy more Phosphoric acid with absolutely no success.
For example a place Castle Chemicals, they said no and told me there are strict controls on the sale of it??

KNOW I DO NOT KNOW IF THIS IS TRUE OR NOT?
But was told it can be used as a key component that they use in labs to make Speed, meth etc with.

I found it odd, I don't know if it is true or not, but that's why I was told why it is difficult to purchase and why they wont just can't sell it to just "anyone".

That is what I was told anyhow and then gave up trying to buy it. It was brilliant stuff, brilliant for cleaning mag wheels etc etc.



 

[Mick D]

Phosphoric acid is the acidic ingredient in molasses and Coke that gives these two products their rust eating capabilities.

There is some evidence that long term exposure to phosphoric acid can cause low bone density / osteoporosis, so safety precautions are required.

CJ

Owh great, now you tell me
Now I am glad that I couldn't buy it

I hope your slow recovery is still going well Col, good luck.
Cheers, Mick.

[Nipper]

 Mick,I have read a bit about the reverse electrolysis it looks pretty simple and by all accounts reasonably safe.
My big concern is the right type of power supply. I have a battery charger but it gives no indication as to the maximum output of the thing, I'm just a little worried about overloading the supply and damaging it. Is there a way to control the current that is being delivered to the anode? or could I use a battery as my supply ? I would like to give this a crack and see how it goes.
Mick what do you use as a sacrificial anode inside of the tank, and how long is long enough with an average size tank?

[fred99999au]

Phosphoric acid used to be readily available for spray painting. Spartan used to have the brand called Deoxidine. It was used over bare steel to give a phosphoric acid coating before an etch primer was applied.

[Mick D]

Phosphoric acid used to be readily available for spray painting. Spartan used to have the brand called Deoxidine. It was used over bare steel to give a phosphoric acid coating before an etch primer was applied.

Arh,,,there you go, I knew some would shed some light Fred.
YOUR story checks out

COPY AND PASTE FROM THE MANUFACTURER
DEOXIDINE * 624 is a phosphoric acid and solvent type metal cleaner and conditioner
designed for manual application, which removes rust, destroys rusting agents and leaves
the metal surface chemically clean and ready for painting. END

I may have been lied to, certainly wouldn't be the first or last time.

[Mick D]

Mick,I have read a bit about the reverse electrolysis it looks pretty simple and by all accounts reasonably safe.
My big concern is the right type of power supply. I have a battery charger but it gives no indication as to the maximum output of the thing, I'm just a little worried about overloading the supply and damaging it. Is there a way to control the current that is being delivered to the anode? or could I use a battery as my supply ? I would like to give this a crack and see how it goes.
Mick what do you use as a sacrificial anode inside of the tank, and how long is long enough with an average size tank?

I use scrap pieces of stainless steel Nipper.

I have never done the anode in the tank thing Nipper, they are WEB IMAGES mate.

Current control is always an issue for me Nipper.
Tried Batteries, too much ferocious activity with no control and batteries are too expensive and dont last long when being full cycled(completely flattened and charged).

Obviously, little pieces don't take as long as bigger pieces.
Placing your anode closer to the worse corroded area is the go.
Surrounding your job in anodes as this bloke has done is also the path to a more even action.
I just hang the lump of stainless next to the worse area
 

[Viper79]

Here you go..

http://www.bunnings.com.au/bondall-500ml-ranex-rustbuster-rust-remover-converter-_p1560847

I used this product painting cars years ago.