# painting galvanized pipe?



## dale rex (Jun 10, 2012)

I never had much luck getting paint to stick to galvanized pipe. I just gave up trying. I have a job that I need to paint some pipe coming up. Any suggestions for getting a quality paint job that will stick indefinitely? Would automotive etching primer be a good primer for this?


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## griz (Nov 26, 2009)

Pickle it first, then a good primer.


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## txgencon (Jan 4, 2011)

griz said:


> Pickle it first, then a good primer.


You may need to translate that for him. (I know what you meant.)


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## dale rex (Jun 10, 2012)

vinegar wash?


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## CrpntrFrk (Oct 25, 2008)

dale rex said:


> vinegar wash?


Yes...


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## MTN REMODEL LLC (Sep 3, 2010)

Galvanize primer:thumbsup:


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## dale rex (Jun 10, 2012)

i just got curious about a bottle of OSPHO that have in my shop. Its a phosphoric acid thats used to convert rust to a paintable hard surface. Kinda like "RustMort". I read the instructions on the back and ist recommended for galvanized metal as an acid etching wash prior to painting. Never tried that product for galv metal.........any opinions on that over using vinegar?


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## ScipioAfricanus (Sep 13, 2008)

I used to use a watered down Muriatic acid to etch galvy.
Use gloves when handling and rinse the metal well afterwards.
Muriatic is just another term for hydrochloric acid.

Andy.


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## gideond (May 17, 2007)

Ospho is fine. We use it all the time for etching galvanized roofs before painting.


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## thom (Nov 3, 2006)

Oftentimes pipe is oily. You may need to remove the oil residue prior to etching. The acid in vinegar will etch a galvanized surface but it probably won't clean and penetrate the oily residue.


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## MTN REMODEL LLC (Sep 3, 2010)

thom said:


> Oftentimes pipe is oily. You may need to remove the oil residue prior to etching. The acid in vinegar will etch a galvanized surface but it probably won't clean and penetrate the oily residue.


THOM.... has a simple but really important fact.

I don't know OP's use, but I use/install alot of horizontal decorative pipe rail (so it's easy to push snow off Colorado decks).

I pickle it, *clean it thoroughly with laquor thinner*, use a tinted galvanize primer and a good exterior latex.

Now the pipes don't get alot of wear per se, but they are exposed to harsh and varying weather conditions.

I've never had any problem or callbacks. (On my own home, I got close to twenty years out of my first coat.... and even the repaint was not really any adhesion problem... just general cleanup of dirt and tree sap crap.)

Best


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## Caslon (Dec 15, 2007)

If zinc galvanized metal has weathered over 60 days, it requires only washing before priming. During the weathering, a film of zinc carbonates forms, which is essentially inert, slightly water soluble, and highly adherent.


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