Rusty Nails On Fence Panels. Rust Inhibiting Primer or Hammerite Direct To Rust before Cuprinol?

[fordfocus2003]

Hello!

I'm hoping for some help as I've been going round in circles working out what to do.

I had some new Featheredge Forest Garden fence panels last summer. I fitted them in the garden and left them for the winter to settle in before planning to treat them with Cuprinol Garden shades paint this spring.

The problem is that every single nail in each panel (there's a lot!) has rusted terribly and also bled down the panel. See pic.



So before I apply the Cuprinol I have to prepare the panels. I've ready a million bits of advice, but the trouble is the rusting nails are punched just below the surface so it's impossible to get to the nail heads to de-rust them properly. + the fact there are loads, it's going to be impossible to remove the rust off all of them.

Anyhow, I think I have two solutions, therefore the question should be simple.

After scrubbing the nails with a wire brush, and before the Cuprinol...

Isopon Zinc 182 Rust Inhibiting Primer OR Hammerite Direct To Rust Metal Paint?

The spray may be easier, but the paint may be better as it's thicker and will may essentially seal the holes.

Both products are here ready to go depending on the consensus.



Thanks loads if you can help!

 

[conny]

If I remember correctly, the Hammerite stuff actually attacks the rust and prevents further corrosion. I would be tempted to go this route. Eventually all the nails will rust no matter what you treat them with.
Many years ago when I had a fence erected by an outside firm I treated the wood shortly after installation, then about 2 years later I went through every panel using screws and treating them after I had finished. 15 years later when I sold the house the fence was still in good condition due to a yearly coating of preservative/stain.

 

[JohnD]

If I remember correctly, the Hammerite stuff actually attacks the rust and prevents further corrosion.

I don't believe it does.

Maybe the formula has changed, but I read a test, I think by AA and they found that although the paint looked hard and shiny, rust grew underneath the paint film, lifting it enough for damp to get under and the rust to spread.

Anyway, I don't like the look of it.

 

[conny]

I'm looking at 25 years+ since I used it so you may be correct John.

 

[fordfocus2003]

Thanks for that.

I went for the Hammerite Direct To Rust as the Isopon Primer seemed to talk like it expected the surfaces to be free from rust (which isn't possible for these nails), but the Hammerite as it says in the name, is fine going straight onto the rust. Check out the dots!



I'll spray it tomorrow with the Cuprinol Garden Shades (2 coats). Only thing is, as the direct to rust is oil based and the Cuprinol is water based, do you think I'd need to sand down the dots? Or should it be ok as they are only small areas?

Lesson learnt reading through your comments Conny - I shall never buy another fence panel ever again with front facing nails. the new tongue and groove panels I had this year have no nails on the outside. Dream!! Talking to the manufacturer (Forest Garden) they do use galvanised nails on the problematic panels, but the process of stamping them in by machine breaks the top surface / nail head and this is how the rusting begins. Re. the Hammerite, I used it on my metal railings and so far so good (1 year) - it says guaranteed for 8 years I noticed - no doubt these days the formula uses less of the strong stuff for environmental reasons.