How to paint galvanised steel posts?

[MattJ]

 

Hi there, have just had a concrete sleeper wall installed to which I will be painting the sleepers and galvanised steel posts.

Just wondering what primer would you recommend to paint the Galvanised steel posts in?

Thanks in advance 

[MitchellMc]

Welcome to the Bunnings Workshop community @MattJ. It's fabulous to have you join us, and many thanks for your question about painting steel posts.

For your galvanised steel posts, the best approach is to use a primer specifically designed for galvanised surfaces. A good option is Dulux Metalshield 1L Light Grey Etch Primer, which is formulated for galvanised steel and will provide excellent adhesion for your topcoat. Before priming, make sure to clean the posts thoroughly to remove any dirt, grease, or oils, and lightly abrade the surface with fine sandpaper, around 180 to 240 grit, to give the primer something to grip. Apply the primer according to the instructions; usually, one coat is sufficient, and once it is dry, finish with a durable exterior topcoat suitable for metal, such as a Dulux Metalshield topcoat or exterior acrylic.

When it comes to painting concrete sleeper retaining walls, one common issue is moisture entering the wall from behind. Unless the rear of the retaining wall has been waterproofed, which is often not the case, hydrostatic pressure from this moisture can push through to the front surface. This can cause any paint applied to the sleepers to bubble or peel over time. Because of this, some thought should be given as to whether painting the wall is the best long-term solution. 

Other options might be to conceal the concrete sleepers if you are not a fan of their appearance. Fixing something like Merbau panels or decorative panels over the sleepers could be an option.

Please let me know if you have any questions.

Mitchell
 

[MattJ]

Hi Mitchell,

Thanks so much for your thorough reply, much appreciated. One question I do have regarding the etch primer, once I apply this I was planning on painting the sleepers with either a concrete sealer or Taubmanns Sunproof as surprisingly enough others have had good results with this paint on concrete sleepers. I have applied waterproofing membrane and corflute to the back of my sleepers so have done all I can to help pull this off. 

Let me know your thoughts

[MitchellMc]

It's great to hear that you've invested the time in waterproofing the rear of the sleepers, @MattJ; that will certainly help. 

I've just had a chat with the Dulux technical team, and if you plan to use Sunproof over the entire area, I would recommend priming the posts with Dulux Precision 1L All Metal Primer - 1L, instead of the etch primer. Once they are primed and dry, you can paint the whole surface.

Prior to priming the posts, scrub them down with SugarSoap and a Scotchbrite pad, then flush with fresh water to remove the SugarSoap. 

Mitchell

[MattJ]

Thanks so much Mitchell that’s great advice.

i just had one question regarding prep of the concrete sleepers, would you recommend anything besides high pressure hose on the sleepers?

Thanks

[EricL]

Hello @MattJ 

I propose washing the surface with detergent and water. This will wash off any oil or grease deposits that may have landed on it surface. You can use ordinary garden hose pressure to wash and rinse the surface of the concrete sleeper. Please make sure the surface and gaps are totally dry before you begin painting the surface.

If you need further assistance, please let us know.

Eric