Painting on galv?
- Thread starter 90maniac
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Turboman
Mab An Gov
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Calcium Plumbate primer! Best to let it weather a bit first.
Jay reKx
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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?
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?
That's why you use a mordant solution first.
brian47
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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.
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.
brian47
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My mistake; re-reading the OP's post I can see he wants to paint over galv, not cold galv bare metal. Sorry.
timtheenchanteruk
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T-Wash (or similar preperation)
new galve cant be painted stright away, it needs to be washed, or weathered in, the zink galve gives off salts when new, weathering washes them off over time, the wash forces the salts out and washes them off.
general rule is, if the galv is dull, its paintable, if its still shiny, it isnt...
new galve cant be painted stright away, it needs to be washed, or weathered in, the zink galve gives off salts when new, weathering washes them off over time, the wash forces the salts out and washes them off.
general rule is, if the galv is dull, its paintable, if its still shiny, it isnt...
Boris113
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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
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
timtheenchanteruk
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bit like that...
timtheenchanteruk
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Then use a brush...
It turns color, any that doesnt needs a clean and re-application till it does, its not coats, its a chemical reaction, so it doenst matter if you miss bits the first time around, you can easily spot it after the reaction, and do those bits then.
It turns color, any that doesnt needs a clean and re-application till it does, its not coats, its a chemical reaction, so it doenst matter if you miss bits the first time around, you can easily spot it after the reaction, and do those bits then.
thought it was mine!
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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
hammerite special metals prime goes straight to galv no need to t wash, dulux do a metal shield primer that goes straight to galv as well its w/b and quick drying, not cheap. It goes on bright or weathered galv just need to make sure it's clean no grease oil etc on galv.
