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pricer
08-08-2006, 07:43 PM
Anybody ever used copper sulfate, in a powdered form, mixed with water to treat galvanized sheet metal prior to painting?

What are some old and/or new ways to treat galvanized for painting? The one I have always heard about was vinegar. I have tested this with mixed results. Zinc chromate primer is another method I have tried with success. It’s almost worth using Galvanneal.

Anybody have any tricks of the trade up their sleeve?

Tets11
08-08-2006, 08:23 PM
I've tried rubbing it with Muriatic Acid on the metal, rinsing it off and then painting. Just tried it, not sure how long or how well it'll work though.

pricer
08-08-2006, 08:28 PM
I have thought of that too. Did you dilute the acid before applying to the metal? On a large scale, I bet it could get very messy and would have to be done in a well ventilated area. I saw a guy one time leave a small jar of muratic acid open in the shop overnight and the bar joist above it was rusty by morning.

Tets11
08-08-2006, 08:35 PM
I didn't dilute it. Not sure if I should have?????

Stickman
08-09-2006, 05:44 AM
I have painted galvanized with latex paint with great success. All I did was just make sure it was clean. The latex paint has something in it that will make it adhere very well. Keep in mind it takes quite awhile for the paint to fully cure. The latex will expand and contract with the metal also. I have some columns on my front porch of my house that I wrapped in galvanize and then painted......15 yrs. later it looks the same. I wish I could say the same for the wood siding !! Anyway back to the preping......they do make a product called GalvPrep and it is a diluted muratic acid solution. If you are going to use lacquer or enamel paint you will need to prep it.

tnbndr
08-10-2006, 05:06 AM
There is also a product out there that I have used successfully in the past called GalvGrip. It is actually a primer that goes on a light translucent blue in color and sticks to the galvanized or any other metal. It remains slightly tacky and then you just paint over it. It works great. I have used it on metal doors, gutters, flashing, etc. I'll have to see if I can find a can with the manufacturers name and will follow up.

LeadHead
08-12-2006, 04:15 PM
I've used Jasco metal prep with pretty good results. I can't remember if we used to get it at Lowes or the local paint supply house. http://www.jasco-help.com/products/prod_mg.htm

pricer
08-12-2006, 09:15 PM
[quote="LeadHead"]IThanks for all of the tips. I have recently used a product called Ospho, it turns rusty metal black like one of the products mentioned in the link. I will have to re-read the bottle to see if it will work for painting galv.

pricerjr
08-15-2006, 08:39 PM
well, in the old days we would use laquer thinner. That did the trick...guess that don't work anymore. lol =)

Bud
08-15-2006, 09:11 PM
Hey pricerjr, nice to hear from you again...how you doing?

pricerjr
08-16-2006, 08:36 PM
doin good bud, been very busy, working hard, been running the shop now, since price started his own thing...I must say bud, you remember when I first started this trade, and now i'm running a shop, well i'm not saying that to boast or anything, but am saying that b/c now i'm so bored with building ductwork...is that bad? I really like custum jobs of some sort...something that needs a new design is what turns my brain on....I'm loving tricky stuff......maybe price was to good of a teacher, and I learned to fast, (not saying that I know It all) maybe thats why i'm bored with it, don't know, but I'm still hackin way!!! good hearin from ya

pricer
08-17-2006, 10:57 AM
[quote="pricerjr"]doin good bud, been very busy, working hard, been running the shop now, since price started his own thing...I must say bud, you remember when I first started this trade, and now i

SteveB
08-24-2006, 09:12 PM
Hey Pricer,
There are two old means of prepping Galvanized for painting.
1- Watered down muraitic acid. And I do not know what the ratio of acid to water is. But it is imperative to mix it. Otherwise the acid will remove the zinc coating entirely; thus removing the protection from rust that zinc coating offers.
2- Vinegar. While basic, it is still an acidic-- acetic acid-- compound. In all my years watching painters prep galv. metal, most have used vinegar.
Since it's been years since I've actually worked in the trade, I'm sure that as technology has progressed, so have the options for prepping metal. It's a cost issue.
A gallon of plain vinegar costs less than a dollar, and goes quite a ways. It just stinks.
A gallon of Muriatic acid costs about 2-5 dollars, and with mixing, it should go even farther than the vinegar. buying a jug of metal prep by Jasco would cost a whole lot more, and not go anywhere as near as far.
Good to see you're still haging out.
Best,
SteveB.

SteveB
08-24-2006, 09:13 PM
Hey Pricer,
There are two old means of prepping Galvanized for painting.
1- Watered down muraitic acid. And I do not know what the ratio of acid to water is. But it is imperative to mix it. Otherwise the acid will remove the zinc coating entirely; thus removing the protection from rust that zinc coating offers.
2- Vinegar. While basic, it is still an acidic-- acetic acid-- compound. In all my years watching painters prep galv. metal, most have used vinegar.
Since it's been years since I've actually worked in the trade, I'm sure that as technology has progressed, so have the options for prepping metal. It's a cost issue.
A gallon of plain vinegar costs less than a dollar, and goes quite a ways. It just stinks.
A gallon of Muriatic acid costs about 2-5 dollars, and with mixing, it should go even farther than the vinegar. buying a jug of metal prep by Jasco would cost a whole lot more, and not go anywhere as near as far.
Good to see you're still hanging out.
Best,
SteveB.