Just curious…
I was originally planning to prep my galv duct for paint using Zinssers 123 primer…
My duct guy told me a better way of prepping it for paint would be vinegar. Wipe the duct down with that and it removes the galv coating.
Just sharing my findings.
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Replies
vinegar is all the gutter guys use before painting galv gutter...
p
make that white vinegar..
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
How come they call it white when it's clear? This world makes no sense.
same reason they call that parking lot (LIE) that runs the length of Long Island an expressway...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
Edited 8/12/2006 9:45 pm by IMERC
I usually wash galvanized parts in a TSP solution, spray a Rustoleum primer, then paint. TSP is cheaper than vinegar, too - lol.
You want to accomplish two things; to remove any oil left from the manufacture, and to roughen the coating so the paint has something to grab.
Vinegar, being a weak acid, does both.
phsphoric acid, it is the main ingrediant in many properitary metal etch compounds.... jasco metal etch is good for this, it will remove light oil, remove surface rust and etch the zink all things leading to a good paint job.
james
I used galva-prep in my car painting days. It does have to be rinsed very well after etching.
yup
what happens if you prime & paint galv metal with out using vinegar or tsp?
peels and blisters...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
next question...
why?
what reacts with the paint?
alligators too...
galvanic salts, oil / lube residue from the manufacturing process...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
didn't know that.
don't think I've painted any glav. metal recently but filed away none the less.
I would have assumed sanding would have been enough.
sanding is a very poor choice of prep method... it won't clean anything.. it'll still leave the salts and oil behind..
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
this is why I work with wood...
not so smarts when it comes to metal
you'll catch on...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
You can put vinegar on fresh galv. all day and watch it bead-up and run off. Got to break up the oil film ( not always easy). If you haven't bought the ducts yet ask about "paint grip". This is galv that has been cleaned and etched to hold paint. Hot soapy water, a good rinse,good primer will be a good start otherwise. Jim Devier
would that be Paint Loc???
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
MIght be, what I see is a dull, darker finish that shiny galv. Needs no prep, prime and paint does it. Jim Devier
Nothing is reacting with the paint to cause peeling and blistering. Paint simply won't stick to untreated galvanized surfaces, so with thermal expansion/contraction the paint and metal separate.Mild acid etches the surface to provide "tooth" so the paint can adhere.Sanding is an awful idea because; a. you can't scratch every part of the surface and b. where the sandpaper does contact it is likely to scratch clear through the zinc, leaving the steel vulnerable to rusting.BruceT
What Marty said .