Painting Galvanised Steel?

[AussieATC]

Any ideas on the best type of paint to do this with?

[barnett468]

e're sure the paint is not the problem. The cause of paint peeling from galvanized metal is failure to do sufficient preparation. Here's how to redo the job right.

In his first career, Kevin painted thousands of feet of galvanized gutter. The first thing he always did was wash the surface of the metal with a mild acid. The galvanization process leaves a smooth, oily film on the finished metal that doesn't hold paint very well. Treating with acid etches the metal and gives the surface a "tooth" for the paint to adhere to. Kevin's acid of choice was plain white vinegar. He came out smelling like a salad, but he never got a call back for peeling paint.

Sand with 320 dry paper if desired, it is yellow do not use black.

Wipe with wet rag

Paint the bare metal with primer designed for metal. Finally, paint the rails a color and paint of your choice. We've always had good luck with acrylic latex, but any good-quality paint should do the trick given the superior preparation we know you'll do. ...CONTINUED

[AussieATC]

So Vinegar - Primer - Paint? I may have already used galvanising primer... what should I do now?

[barnett468]

Hello

It depends upon how long you need it to last. If it's a small area and it will be exposed to the outdoors then you can remove the primer with cheap lacquer thinner from the hardware store and start over. Otherwise just leave it and hope for the best. The primer should be sanded lightly with 400-500 dry paper.

[AussieATC]

I think ill just give it another coat of primer and that's, it would that work as well?

[FLynes]

Long story short, you can't; you have to do what barnett468 said and remove the galvanic coating, which defeats its purpose. Guys on the Jeep Forum I belong to buy aftermarket galvanized frames and then want to paint them.....makes no sense to me, since the cost of galvanized frames is a lot more than a regular aftermarket steel paintable frame.

[AussieATC]

Well actually I wanted the thinnest square tubing possible and that only cam in galvanised and it was cheaper aswell...

[Mr. Clean]

e're sure the paint is not the problem. The cause of paint peeling from galvanized metal is failure to do sufficient preparation. Here's how to redo the job right.

In his first career, Kevin painted thousands of feet of galvanized gutter. The first thing he always did was wash the surface of the metal with a mild acid. The galvanization process leaves a smooth, oily film on the finished metal that doesn't hold paint very well. Treating with acid etches the metal and gives the surface a "tooth" for the paint to adhere to. Kevin's acid of choice was plain white vinegar. He came out smelling like a salad, but he never got a call back for peeling paint.

Sand with 320 dry paper if desired, it is yellow do not use black.

Wipe with wet rag

Paint the bare metal with primer designed for metal. Finally, paint the rails a color and paint of your choice. We've always had good luck with acrylic latex, but any good-quality paint should do the trick given the superior preparation we know you'll do. ...CONTINUED

Copy paste much from the Internet Kevin? :lol:

http://www.inman.com/InmanINF/bonnierossell/news/106766 :rolleyes:

Hope this helps

[barnett468]

I think ill just give it another coat of primer and that's, it would that work as well?



Hello


Unfortunately the potential adhesion problem is at the surface of the metal therefore adding more primer will do nothing to prevent it from lifting if it is going to. The quality of spray can paints is far inferior to professional grade automotive paints and many house paints such as “elastomeric” types and “lotus” brand therefore they are also less durable.

Due to the susceptibility of damage to spray can paints to the weather and UV rays it is possible the spray can paint may simply “fail’ before your primer lifts from the metal anyway but I doubt it.

Unfortunately other than Flyne’s post and mine you have not yet received any other posts of any value whatsoever from any other members and that also specifically pertain to your specific question.



Hope this info helps.

[AussieATC]

In that case is there a good way to remove the primer?

[barnett468]

In that case is there a good way to remove the primer?


Hello AussieATC


Yes, I answered that in post number 4, cheap lacquer thinner from home depot etc, ask the guy for chemical resistant gloves, buy lots of paper towels, it will make a mess. Wipe them down outside. If it is cool with a slight breeze it is better, the fumes are dangerous. You can also have them sandblasted by an expert with low pressure or hand sand them with around 280 dry [yellow] paper. Flynes or another may other suggestions.


Hope this info helps.

[FLynes]

Put a sanding disc on your grinder, wear a mask because this stuff is poison to breathe, and sand it off....that's the easiest way. Forget etching it, just sand it.

[AussieATC]

Will that damage the metal under it though?

[FLynes]

No, because the galvanizing is just a coating. All you're doing is removing the galvanic coating. Honestly, you're better off buying the regular non-galvanized square tubing and saving yourself the hassle. By the time you're done spending the time and money taking the galvanizing off, you would already have painted the regular tubing.

[AussieATC]

Hahaha I know well i painted most of it with the primer and that's going to be it. If it peels it wont matter as there is galvanised under it and the paint will still stick to the welds were it is needed the most.

[poplama]

I do a lot of fabrication using both galvanised rhs, and hot dipped galvanised chinese steel. I generally just use cold galvanising spray on the welds and it all works out fine. This is in chicken sheds mostly which is a horrible place for corrosion and all seems to work pretty well. The color seems to blend in with the galv well too. A lot of the time the galvanised steel will be sprayed with a light oil too that is there to prevent what is called white rust forming om the surface when the coating is exposed to moisture during storage. If you use a good solvent to wipe it down before you paint it this will normally save any dramas. You wont get a ferrari shine, but you will get a red coat that will stay for ages! i have made steel guards and rack on my 250es which are all galv and the paint sits on em fine. i just use dulux primer and wildfire red. you can get it from bunnings and it looks flash as michael jackson!

[poplama]

My camper trailer i built four years ago and have had on the beach was made from only cheap gal rhs with cold galv spray on the welds and still has bugger all in the way of even surface rust even after being on the beach numerous times