Im hopefully getting a galv chassis at some point ib the forthcomming months what paints do i want to use i have heard galv can be a pain to paint on
Galvanized Steel is a material that has been coated with a zinc coating to prevent rusting.
Probably the most likely form of this that the amateur is likely to come into contact with is Zintec sheet.
Like all types of galvanised materials zintec has been designed to resist rusting and by default it also resists acids, hence etch primers do not work on it.
Unlike Stainless Steels, Galvanised Steels have a problem, in that the galvanised coat will start to break down if left outside in the garden.
Commercial applications of galvanised steel apply a protective coat of paint to the metal by powder or dip coating.
As neither powder or dip coating are generally available to the amateur, the only option with galvanised steels is to leave them in the garden for
approximately 24 - 30 months thus starting the breakdown of the coating and allowing a two pack etch primer to get a hold.
I'm confused
Etch Primers - what are they?
they says etch primer wont work on galv unless its weathered for aaaages and started to break down (also this is the first time i've heard of galv 'breaking down') at whih point wouldn't its start to rust, which is what you're trying to avoid :???:
or have I got the wrong end of the stick somewhere?
I haven't used the stuff myself, but I've seen it used by a company who did some steel erection and fabrication work for a previous employer.
After cleaning up their welds; chipping away the slag and flux, they used Galvafroid to brush-paint over the work. It seemed OK to go straight onto the job without any other preparation or priming and if I remember right there was no rust showing even after a year or two outside in all weathers.
It does seem to be a bit expensive, but you only get what you pay for.
What Tim said is bang on the money.
Mordant solution (aka T-wash), brush on liberally, watch the galv change colour then hose off.
Etch primer (I used Hammerite specials metals primer because it was on offer)
Then a top coat of your choice![]()