Wow, since it looks like we may be done with all the BS, maybe I can explain in short why the confusion.
Not sure why I want to bother after seeing BS like I will do a ph test or half statements like it say it will help adhesion, with out pointing out that every one of PPG tech sheets on their acids say water, water and water.
Zinc rich epoxy in automotive refinish??, No such thing and you can figure it out after reading what I try to say.
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Pats zinc rich rust remover works pretty well. You dont rince it off while wet either...Like Ospho you want that coating so the bare metal dosent start rusting again after you've finished removing the heavier rust or after stripping paint.That zinc coating MUST be removed BEFORE priming.Think about it,the zinc disolves in the acid ,when the acid drys or evaporates the zinc remains,its stuck on there like the paper towel that was left to dry.theres no resins gluing it down so its not stuck on there very well...it needs to be sanded off and preped properly for good adheasion...Ospho doesnt have zinc but still needs be sanded to get the coating off and properly prepped before priming
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First like I said many times, the automotive refinish is a very small market compared to the industrial market and products are different for a reason!!!!!
So when mail order companies buy acid mixes and slap their label on them, the industrial company that makes this product big business is industrial, remember Dead body man saying Ospho telling him, auto refinish would not pay their electric bill a year ago??
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I have no idea what thier elec bill is I dontthink they do either I never talked to any accontants ....What I stated was automotive industry accounts for only 1% of their total sales.....Thats a LOT...
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Now epoxy or urethane can be made 100’s of ways and this is why with the purchase of ameron seven years ago by PPG, (Ameron made only epoxies and the best in the world.)
I bet PPG has over 30 different epoxies but only one in auto refinish, why? The industrial grade will not work.
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LOL,ILMAO..They're automotive grade dont work very well either....:mwink:
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Neutralizing: If you are selling to stationary objects, or 3 MPH dozers you do not need to neutralize as a 30-50 % adhesion rate and a ton of zinc is perfect for the job but on a car or truck doing 70 mph if he hit a bug or stone a nice big chip is going to happen.
Zinc is a formulators dream but in automotive there is a most important factor that trumps everything, “co-adhesion this is not a concern or most likely not even measured in industrial, in automotive, if this is wrong you are in deep chit!
Zinc positive is rust and its weak point if too much is used you start to lose adhesion and or co-adhesion depending how it is used, 1percent to much mixed in auto refinish and you can really cause a mess.
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I'm not crazy about the zinc coating either its just one more thing to get off.
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I would bet from old knowledge, some of the Ameron epoxies for the oil stations may be in the 50% range, yet automotive epoxies may be 1-10% depending on they type of epoxy resin that is used in the formula.
So bottom line is both sides are right, depending on applications, I posted on a forum a while back about how I get over a 100 calls a year from metal treatment products that fail because they were not neutralized, like they are suppose to be
--------------------------------------------response:Thats usually the case when theres an arguement
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The best one was the PPG shop in another post who wanted my opinion if ppg epoxy was bad, thirty minutes of questions, I said sir, you did everything perfect, and I asked you a lot of trick questions and can tell you the LF and K36 were just fine and with what you said as to how you did everything, the car cannot peel like you said.
Then he said what if I used this metal treatment the customer brought me and said use after blasting? I said we could have saved 30 minutes of me interrogating you. Oh that is one of those private label miracle metal prep sold by a mail order company that attacks do-it-yourself market because they don’t know any better.
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sounds about right...but if he was a pro he never would have used any of that crap in the first place.....that customer might have said it was media blasted but if the media was sodablasted it would have done the same thing, peel off...soda blasted metal is prepped differently....unfortunately sandblasted is a general term used that shouldnt be...
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Bottom, line, follow TECH SHEETS, or call me when the paint has a problem, if you give me the straight scoop on size, location of bubble and where, I can tell you, if you washed the metal with lacquer thinner, or did not neutralize the Ospho, or if you used merratic acid and can tell you if you used hydrochloric, as they all cause a different reaction.
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