severe corrosion of posts

[jadajake]

Hi All,

I have some posts out front that I have cleaned up as best as possible. I have attached a photo of the top of one of the post (all 3 posts pretty much look the same) that I would like advice on what to use in protecting them from further rusting.

They were severely rusted and as you can see have very bad pitting too and the steel just stays black after using flapper disks/wire brush to remove all visible rust. (there is rust visible but that has only appeared in the last 12 hours so will clean that off before going forward)

I have done some research but just want to make sure I am heading in the right direction. 

Option 1 - Apply white Knight Cold Gal, then apply White Knight True Bite, then apply top coat which would be Taubman's Monument Grey Exterior

Option 2 - Apply White Knight Rust Convertor (only as not sure what the black is where I have wire brushed using drill), then apply White Knight Metal Primer, then apply top coat which would be Taubman's Monument Grey Exterior

Thanks in advance for your advice

[JacobZ]

Hi @jadajake,

A warm welcome to the Bunnings Workshop community and thank you for your question.

I would go with option 2 as it will treat and convert any surface rust that appears before your primer is applied whereas applying galvanising spray will just cover it up.

Allow me to tag @Nailbag and @Jewelleryrescue for their thoughts.

Let me know if you have any further questions.

Jacob

[Noyade]

If possible @jadajake, is there someone who can weld new pieces on, preferably galvanised? Is it 50mm X 50mm?

That would be Option 3 for me.

Cheers.

[Jewelleryrescue]

Hi @jadajake 

That steel is still structurally sound, all be it having deep pitting it isn't Swiss cheese by a long shot.

The black is the rust converter residue, But the brown is fresh rust so re use  rust converter on a warm  day. Let it dry and hit it with cold gal spray  ASAP to stop the metal exposure to water moister.  I prefer

  Dy-mark Zinc Gal    as it has the highest concentration of zinc etc and is cheaper than other paints on hand.

If you wanted to remove the pitting hit it with an angle grinder and metal cutting disk. and use Gal spray ASAP afterwards same day.

[Nailbag]

Hi @jadajake 

I agree with @Jewelleryrescue that there is plenty of meat left in the steel, and the bulk of the damage is still relatively cosmetic. Though unless I'm misunderstanding the instruction, he may have meant a metal "grinding disk", not cutting? However a 40 - 60grit flap wheel on your angle grinder will very quickly and effectively smoothing out the pitting to a smooth shine.

Nailbag