How do I water proof rusty cast iron toilet cistern?

[mojouk]

Hi,

I have an old victorian cast iron toilet cistern. It's rusty inside and out.

I would like to protect the inside from corroding any further (as it holds water all the time), and the outside from rusting.

I have already looked at paints, like Hammerite - which say you can paint directly onto rust which seems ideal.
But I don't know if you can paint Hammerite on the inside of a toilet cistern, when there is water inside it all the time.

Also, Hammerite says that it lasts up to 5 years only - and I'm looking for something that will last much longer - so I never have to strip this cistern again (in my lifetime anyway).

So, any suggestions would be much appreciated!!

[thescruff]

Hi,

Cast iron doesn't rust, so whatever you have will only be surface.

[mojouk]

Sorry. I probably meant that the iron on my cistern is corroding (not rusting).

I have already stripped it free of paint. Now the outside layer has a thin orange layer.
The inside of the cistern is also quite orange but is also lumpy - which I guess is caused by the water.

I'm trying to find a product that will permanently seal and waterproof the inside and outside, and then finish with a paint for metal...

This was my 3 step plan to use the following products....

1) Hammerite Kurust (Converts rust into a sound surface)
2) Hammerite Waxoyl (Kills old rust and prevents new rust from forming.
Forms a flexible, weatherproof skin that doesn’t crack, dry out or wash off in the rain).
3) Hammerite Metal Paint (direct to rust Metal Paint. Performs as a primer, undercoat and topcoat in one. Long lasting corrosion protection)

Does this sound like a sensible solution?

[thescruff]

Surface lumps should knock off, but you need to be careful, perhaps a pic showing the problem would be a good idea.

The best product is red oxide, then paint the outside as normal.

[Colour Republic]

Owatrol oil I'd favour over red oxide ;)

[thescruff]

Owatrol oil I'd favour over red oxide ;)

Why it's expensive and unnecessary.

[mojouk]

The idea is that I don't want to ever have to take down my toilet cistern and strip/paint it again (in my lifetime. i.e. next 50 years).

So - with this in mind, which is best?

Waxoyl:
http://www.amazon.co.uk/Hammerite-50928 ... 033&sr=1-6

Owatrol:
http://painterschoice.co.uk/paint/owatrol_oil.htm

Red oxide paint:
http://www.amazon.co.uk/dp/B001GU8C2G/r ... B001GU8C2G

The price isn't an issue - as the difference is only a few pounds between the 3 products. I just want something that will last a very very long time

[Colour Republic]

Owatrol oil I'd favour over red oxide ;)

Why it's expensive and unnecessary.

I've had red oxide flake off plenty of times when it has become tired and it needs to be painted on when the metal is clean, where as owatrol doesn't need to be clean and will bind with the metal.

On the subject of lasting 50 years I don't think any coating would last that long unless it was factory applied and even then you're pushing it.

[ayjay]

The idea is that I don't want to ever have to take down my toilet cistern and strip/paint it again (in my lifetime. i.e. next 50 years).

So - with this in mind, which is best?

Get a ceramic one.

[scot-canuck]

Enamel it or have it powder coated?

Nothing will stick to waxoyl...its like bitumen...and might *eventually* dissolve into the water.

If you were really intent on keeping it long term....have someone blast it, and paint it with the paint they use on oil rigs....20 odd year anti corrosion warranty on that stuff....I know someone with a gate that was painted with that, and its been outside for 10 years with no signs of fading or corrosion....