# Forum Home Renovation Metalwork & Welding  Steel Frame Corrosion  Maintenance

## mojorising

I have a steel frame supporting a water header tank. About 20 years old.   
It has signs of rusting.   
For maintenance I was planning to strip the rust off and then spray with grey primer. 
Is that the best plan? 
I have tried stripping the rust using a sander and also a wire brush each attached to my drill.   
The sander cleans the steel pretty thoroughly but does not get into all the contours. 
How thorough does the rust removal have to be? Is 90% good enough or does it need to be gleaming steel 100%? 
Is there any chemical solution that will get in the grooves if it needs to be 100%?

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## Marc

Use a steel brush on an angle grinder. Protect yourself with face mask and long sleeves, the wires fly and hit pretty hard. 
Once you have removed all the rust as best as possible .. 98.5%  :Smilie:  ... then find a good cold galvanising primer, and coat the section you cleaned. In your cleaning quest, try not to remove the zinc that is in good nick where there is no rust. That would be a shame. Sander will remove the old galvanising. Don't do it that way. Wire brush is the way to go.
When you have covered the naked steel with cold gal, where the rust used to be, cover the lot with Luxepoxy 4 primer. It is an industrial paint by Dulux ... It is a primer yet it is so tough that is used in public works and does not need a top coat. You can coat it with any paint if you don't like white, but it does not need it  :Smilie:

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## doovalacky

I've had good success with the wattle killrust product. Painted lightly rusted black steel after a rough brush over and its still good after 10 years in the weather. 
Just used the top coat version too.

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## joynz

Just use a rust converter then paint over with an anti rust primer and top coats.

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## METRIX

It's only surface rust, as Marc said wire brush on drill or grinder, then cold gal spray, any brand they all work
Make sure to remove rust thoroughly back to bare metal, no need to overcoat with anything if you don;t want to. 
https://www.bunnings.com.au/dy-mark-400g-zinc-gal_p1580554 
.

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## mojorising

^^^^Thanks Marc and others. 
I was not getting far with the wire brush on the drill so I switched to sandpaper. 
But I will switch back to wire brush on angle grinder 
And finish with ​​​​​​cold galvanising primer. 
Great.

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## Marc

I wouldn't use spray. Too large of a surface. Use good old paintbrush. the spray coat is way too light and will rust again unless you top coat it.

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## droog

There are different types of Zinc sprays, one is a primer only and must be top coated. There are also some that are suitable to be used as a final finish, make sure you check the type you get.

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## mojorising

^^Thanks Marc
^Thanks Droog
I will be sure to get the right stuff.

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