# Zinc power and epoxy



## Mc 75 (Apr 5, 2016)

Has anyone ever heard or done putting zinc power into a 50 50 macropoxy? If so how did it do


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## CApainter (Jun 29, 2007)

No..


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## Mc 75 (Apr 5, 2016)

I have never heard of it either but someone told me about it and it got me thinking about how it would work


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## journeymanPainter (Feb 26, 2014)

Mc 75 said:


> Has anyone ever heard or done putting zinc power into a 50 50 macropoxy? If so how did it do


What are you putting it on?


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## Mc 75 (Apr 5, 2016)

Raw steel


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## Mc 75 (Apr 5, 2016)

journeymanPainter said:


> What are you putting it on?


Raw steel


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## DeanV (Apr 18, 2007)

Calling NACE.


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## kmp (Jan 30, 2011)

There are plenty of nasty zinc primers out there that are meant for bare metal and would do a better job than some thing home made. Factory mix gives a warranty as well.


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## journeymanPainter (Feb 26, 2014)

Mc 75 said:


> Raw steel


Where is it going? 

Zinc is used as a sacrificial element. By adding it to your finish you may cause your finish to prematurely fail.

I would suggest zinc coatings. 
@NACE should be able to give your good products and procedures


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## mustangmike3789 (Jun 11, 2011)

mc 75 said:


> raw steel


atmospheric or immersion service ?


Carbozinc 11 or zinc clad from sherwin williams is a good place to start if you need a zinc coating. It will be important to clean the surface to at least a sspc- sp 6 / nace 3 with at least a 2 mil profile. You will also need a sprayer that has an agitator that can keep the zinc solids suspended while in the pot.


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## CApainter (Jun 29, 2007)

mustangmike3789 said:


> atmospheric or immersion service ?
> 
> 
> Carbozinc 11 or zinc clad from sherwin williams is a good place to start if you need a zinc coating. It will be important to clean the surface to at least a sspc- sp 6 / nace 3 with at least a 2 mil profile. You will also need a sprayer that has an agitator that can keep the zinc solids suspended while in the pot.


And most likely, it will be an inorganic zinc. It really takes some skill to spray that stuff. I never did get really good at it. But to answer the OP, I don't think adding zinc powder to a generic epoxy is advisable. 

Zinc is designed to be applied, by itself, to a properly prepared steel substrate, and is the last line of defense in many barrier coatings, It has the ability to mend itself by oxidation I believe. Mike?


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## mustangmike3789 (Jun 11, 2011)

CApainter said:


> And most likely, it will be an inorganic zinc. It really takes some skill to spray that stuff. I never did get really good at it. But to answer the OP, I don't think adding zinc powder to a generic epoxy is advisable.
> 
> Zinc is designed to be applied, by itself, to a properly prepared steel substrate, and is the last line of defense in many barrier coatings, It has the ability to mend itself by oxidation I believe. Mike?


Sounds right and yes it can repair itself just like galvanizing. Recent studies have shown the inorganic zinc does not have to be top coated for that very reason and that it actually performs better without a top coat because it will allow oxidation to happen. 
Zinc does take some practice to get right. Not enough mils and you get pinpoint rusting. Too much will cause mud cracking. Repairs and recoats may require an organic zinc or an epoxy mastic or you may have to blast the entire area if inorganic needs to be applied because it does not like to stick to itself after curing.
Top coating zinc does not pose any real problems to either coating unless it is applied wrong. Zinc is very porous and has thousands of air bubbles trapped inside of it because it cures so fast wich can cause blisters to form in the coating applied over it unless a mist coat is applied that will let the trapped bubbles to fill or escape if a hot solvent coating is being used such as an epoxy.


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## NACE (May 16, 2008)

mustangmike3789 said:


> atmospheric or immersion service ?
> 
> 
> Carbozinc 11 or zinc clad from sherwin williams is a good place to start if you need a zinc coating. It will be important to clean the surface to at least a sspc- sp 6 / nace 3 with at least a 2 mil profile. You will also need a sprayer that has an agitator that can keep the zinc solids suspended while in the pot.


This is exactly the correct recommendation.


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## pacific paint (Nov 21, 2015)

What has always entertained me is picking up a 2 gallon pail of zinc powder it's so heavy for it's size. Around 118 lbs.


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## CApainter (Jun 29, 2007)

pacific paint said:


> What has always entertained me is picking up a 2 gallon pail of zinc powder it's so heavy for it's size. Around 118 lbs.


I know what you mean. I used to hate carrying those squashed metal fives. They may have only been three gallons, but they felt like I was trying to pick up three full fives of paint with one hand!

And all the other stuff that went with spraying inorganic zinc was a PITA. The agitator. The build up of zinc on the air cap. The crappy finish if it was too hot, windy, and in a hard to get area, which for me, always seemed to be around a muddy freeway underpass.


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## blackatom (Sep 8, 2011)

NACE said:


> mustangmike3789 said:
> 
> 
> > atmospheric or immersion service ?
> ...


No it really isn't. 
First of all, I doubt it's immersion service.
Second, why would you suggest a commercial blast and inorganic zinc to someone that is asking about tossing zinc dust in macro? No offense, but I would probably want that person to have something a little more forgiving (organic).
Third, CZ11 calls for a 1 mil profile minimum.

Go with Carbozinc 859 from Carboline or Zinc Clad III HS from S-W. Heck, I'd even say go with an epoxy mastic like carbomastic 15FC or epoxy mastic aluminum ii.

Inorganics have places that they shine, but they are way overspec'd. See above for my case in point.


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## mustangmike3789 (Jun 11, 2011)

blackatom said:


> No it really isn't.
> First of all, I doubt it's immersion service.
> why do you doubt that it could be for immersion service ? I agree that it should not be used for immersion in salt water but it can be used in non potable or deionized water just like metalizing, when aluminum is speced instead of aluminum and zinc mixed in salt water.
> Second, why would you suggest a commercial blast and inorganic zinc to someone that is asking about tossing zinc dust in macro?
> ...


....


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