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Discussion Starter #1
I was wondering something about bare steel..i know you need to have a metal prep to clean off the steel and apply epoxy on bare steel but i heard about a metal conditioner are you suppose to use a metal prep,and apply some kind of metal conditioner to it or are you just suppose to use metal prep then apply epoxy?
 
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The process depends on the brand of epoxy you use. Some only require bare metal to be sanded with certain grit paper, then apply the epoxy. Some of the other brands may require additional proceedures and products, for their product to work. Of course all of that should be considered when looking at the costs also.

Aaron
 

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PPG recommends you use both, first the 579 cleaner to clean and etch the metal,then rinse and then follow with the 520 conditioner to convert rust, leave a zinc phosphoric coating and rinse again with water. You can apply them with a scotchbrite pad. Both contain phosphoric acid but the conditioner also leaves a the coating on the metal. Then follow with epoxy primer. It is very important that you neutralize these products, and an acid etch primer is not recommended over them. You either use the metal conditioners or spray on etch primer before epoxy, not both. If you have blasted metal, I may be wrong, but think metal conditioners also aren't recommended because 1) they shouldn't be needed of blasted well and epoxy primed soon and 2} it could be difficult to neutralize properly. Honestly its been so long since I've used them, I had to look at the tech sheet, and ppg doesn't give a real lot of information. If you can use them alone, guess thats your gamble. Is it worth it, when in the realitive scheme of a paint job, the cleaner and conditioner are pretty cheap? If you just need the etching propertys and not coating, rust conversion, i would think the cleaner alone would be fine, if you spray epoxy primer soon.
But I am with the others, Hopefully you are getting rid of the rust and if you sandblast or sanding the metal and its clean, there would be really no reason you would need a conditioner, Just spray your epoxy Primer on as soon as possible. I don't like rinsing bare metal with water or risk the possibility of acid get into a seam somewhere and somehow not getting neutralized properly if it isn't really needed.
Disclamer: The advice given here is based on his opinions/beliefs and reference materials in an attempt to help with a question, and he does not claim to be an expert on metal conditioners. Consult with your product manufacturers tech support.
I assume no responsibility for anyone's use of the contents or information or for paint bubbling or flying paint sheets at highway speed in the future. :D
 

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PPG DX579 and DX520

I have had a problem with rust coming back bubbling the paint on the roof my 67 camaro. I had it painted twice by different body shops. I have stripped the roof to bare metal and I have used Naval Jelly to try to get rid of the rust. I have the PPG DX579 and DX520 too. What I was wondering if I could add something like baking soda to the water to rinse and help neutralize the acid cleaner DX579. Then apply the DX520 metal conditioner.
 

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I haven't used metal conditioners in years ,in fact with todays technology they are a thing of the past and i feel they cause more damage then good. I 80 grit the metal then clean with a water born and a solvent born precleaner then put on a self etch or bare metal epoxy depending on what the part is going to have happen to it after wards. I mostly used the bare metal epoxy because you can do body work around it. I have found that metal conditioners cause flash rust that will haunt you later down the road. JMO Tim
 

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Flash rusting is indeed a problem in the time frame between taking to bare metal and primering. It starts immediately, just from the humidity in the air.

Eastwood sells a product called "Metal Wash", that prevents flash rusting for several weeks. It's in a powder form that's mixed with water before application, and is a mild etch and can be painted over.....
 

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Brian Martin,Freelance adviser
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lets cut it up said:
I haven't used metal conditioners in years ,in fact with todays technology they are a thing of the past and i feel they cause more damage then good. I 80 grit the metal then clean with a water born and a solvent born precleaner then put on a self etch or bare metal epoxy depending on what the part is going to have happen to it after wards. I mostly used the bare metal epoxy because you can do body work around it. I have found that metal conditioners cause flash rust that will haunt you later down the road. JMO Tim
My thoughts exactly. Clean metal covered with a quality epoxy or etch primer and there is nowhere for any microscopic rust to go. And if it is etch primed, even the microscopic rust has been neutralized by the acid in the etch primer (the whole concept of the stuff).

Brian
 

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As far as I'm concerned metal conditioners went out with the hair bands. No way would I use them today especially if your talking about a completely bare car. You will end up getting water in places you couldn't treat and It dries to fast and leaves a white coating of acid you can't wash off then you continue to reapply and the mess gets bigger and then you finally wash it off with water and it flash rusts. In our shop we use 80 grit on a DA Scotch rollock disks in the nooks and crannies hand sand what you have to to give it tooth wipe down with grease and wax remover and apply DPLF Epoxy.
 
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