How to neutralize Ospho

Not a criticism directed at anyone, more just an observation. For the life of me I don't understand why so many folks want to use epoxy, but don't want to follow the directions for it's use. There are no shortcuts to quality.
Spend some time on Facebook and you will gain an understanding. It’s a jungle out there and the advice given spans one end of the spectrum to the other. Some real crazy chit there and the folks delivering are adamant it is sound advice.

Don
 
Too much snake oil out there that promises the world, so easy with no effort. They’ve heard all such stories on all the car forums and believe it hook, line, and sinker. Would rather trust a keyboard warrior who touts how easy the product is than follow the manufacturer’s instructions. Yeah, I think I’ve been called an asshole on many occasion because I dare speak ill of the snake oil products.
 
Yeah, I think I’ve been called an asshole on many occasion because I dare speak ill of the snake oil products.
Hard to believe anyone would call you that. You are one of the nicest guys on the forums I've seen you on. The only time I ever remember you being critical of someone is when you were talking about that guy on GarageJournal, who incidentally loved POR-15 as well.:)
 
Neutral pH is 7.0. Looking at the data sheet you linked to the pH of the product is 5.9. That makes it slightly acidic. It also showed that it is up to 90% water. My guess is that it is similar to Ospho and uses phosphoric acid, but is much weaker thereby requiring longer to work. Irregardless it is still slightly acidic and therefore would leave an acidic film if not neutralized.

Molasses pH is in the mid 5's. Similar to this stuff.

Molasses, evapo-rust, rat piss, it doesn't matter. If it is acidic it needs to be neutralized if you plan to use SPI Epoxy over it. End of story. Any other questions refer to the first post.:)
Leave molasses alone. Molasses doesn't contain zinc and doesn't reactivate when rehydrated. There's no "guesses" in chemistry. Your out of your lane when making comments on acid reactions or chemistry. If you've got some some sorta chemistry certification, upload it and continue, otherwise, stick to paint etc. End of story. Any other Q's refer to paint, painting techniques etc.
 
Hard to believe anyone would call you that. You are one of the nicest guys on the forums I've seen you on. The only time I ever remember you being critical of someone is when you were talking about that guy on GarageJournal, who incidentally loved POR-15 as well.:)
Another TV show faux pas that I saw... Fantomworks had a rusty one in, roof was terribly rusty, Dan explained how they used a product to convert and paint over rust and that it sealed it forever. I kinda like that guy but this again, made me lose a little respect for another tv restoration guy that's supposed to be a restoration god. Still like his shop though.
 
Leave molasses alone. Molasses doesn't contain zinc and doesn't reactivate when rehydrated. There's no "guesses" in chemistry. Your out of your lane when making comments on acid reactions or chemistry. If you've got some some sorta chemistry certification, upload it and continue, otherwise, stick to paint etc. End of story. Any other Q's refer to paint, painting techniques etc.
Rln, other than the molasses comment are his other comments abt neutralizing acids for epoxy adhesion not true?
 
Leave molasses alone. Molasses doesn't contain zinc and doesn't reactivate when rehydrated. There's no "guesses" in chemistry. Your out of your lane when making comments on acid reactions or chemistry. If you've got some some sorta chemistry certification, upload it and continue, otherwise, stick to paint etc. End of story. Any other Q's refer to paint, painting techniques etc.
You most definitely are correct about me not being a Chemist.:) I wasn't trying to be insulting or dismissive to you with my comment. I wasn't directing it at you either. Sorry if you took it that way.
All I said about "acid reactions" or "chemistry" was very simple, and just repeating what I have been told...."Epoxy, specifically SPI Epoxy, doesn't adhere to an acid film" If what you or others mentioned using doesn't leave an acid film if not neutralized is true then could you explain how that is?
If you can explain it, how would using molasses with it being acidic, would not leave an acidic film when done using it? That was the point of my comment. And a weak acid is still and acid correct?
I do not recall mentioning anything about how to go about neutralizing molasses specifically. If you are rinsing when done with it and that neutralizes it you should have explained that in your post. People who read it and try it might not realize that.

What I said at the end was referencing what Barry said in the first post, which was that SPI only endorsed using three products as acid treatments and that folks asking about other types of acid treatments was kinda moot.
 
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Those of us old enough to remember the car batteries that weren't sealed also remember the holes left in our clothes and skin from the acid that got on us. Why would acid in anything else be different?
 
The only time I ever remember you being critical of someone is when you were talking about that guy, who incidentally loved POR-15 as well.:)

To be fair, his finished work looks very nice. To be honest, paint and mud hide a lot of hack work, even worse than his use of POR and spray can products .

This one time he installed a power window motor on long straps and when the pendulum effect slammed the motor into the door skin when closing the door, a chunk of mud fell out 1/2” thick, leaving a crater in the freshly finished door. But it looked real nice before that. :p



Door mud.JPG
 
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I always enjoy this guys videos. I am not sure if he tests things the absolute correct way, but he definitely puts the time and thought into his videos.



*** I have never used any of these products on anything other than the vinegar/water trick once on some rust under a t-top weather seal. Not really sure how it held up, 5 years later I cut the roof off anyways!
 
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Funny thing, when I was 16 I worked at Sherman and Associates the company that used to supply Chinese car parts. No real clue about cars yet other than stereo shit, but when we had bare metal parts that had to ship out and if they had any surface rust they would make us grab a scotch brite pad and some "Rust-Mort" and wash the panels down.
 
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Neutral pH is 7.0. Looking at the data sheet you linked to the pH of the product is 5.9. That makes it slightly acidic. It also showed that it is up to 90% water. My guess is that it is similar to Ospho and uses phosphoric acid, but is much weaker thereby requiring longer to work. Irregardless it is still slightly acidic and therefore would leave an acidic film if not neutralized.

Molasses pH is in the mid 5's. Similar to this stuff.

Molasses, evapo-rust, rat piss, it doesn't matter. If it is acidic it needs to be neutralized if you plan to use SPI Epoxy over it. End of story. Any other questions refer to the first post.:)
Evaporust is a chelator, it doesn't strip by acid.
 
Good to know. Just wondering, being that it's slightly acidic, wouldn't it still leave an acid film if not rinsed?
To put it into perspective, a phosphoric acid solution at pH 2 is about 10,000 times more acidic (10,000x more hydrogen ions to donate) than a solution at pH 6! Even the pH of the water you're rinsing with can range anywhere from 6-8.

Let's get controversial. You make lots of previous comments about acidic pH. I am willing to wager that epoxy incompatibility with phosphoric acid is not a function of pH at all but the chemical and/or associated film itself. Enter evidence exhibits:
  1. In order to have a pH, a substance must be aqueous, containing water. A dry panel will not have a pH, nor will a solvent or an oil contain a pH. Epoxy itself probably doesn't actually have a pH either; therefore why it would be sensitive to pH?
  2. The 'neutralization' step for phosphoric acid isn't actually neutralizing the pH AT ALL but merely rinsing the bulk of the chemical itself off the panel. Thus the H2PO4 and its film on the panel is merely a contaminant that must be removed. If epoxy were actually sensitive to pH then a water rinse alone would be a massive failure.
  3. Because A). only an aqueous solution can contain a pH, B). a dry panel has no pH, and C.) epoxy has no water, then a panel with an acid dried on it and subsequently sprayed with epoxy would still have no pH. Therefore it would be neither acidic nor basic. There is no water in the system.
With that, my hypothesis: The incompatibility is the fact that the phosphoric acid is a surface contaminant and has nothing to do with pH.

Evaporust notwithstanding, despite its higher pH, would need to be rinsed off too.
 
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Thanks for the detailed explanation Lizer. Obviously I am not a Chemist. So the acid film has nothing to do with pH and is because it's a contaminant? Interesting.
 
if i had a long term project such as a chop top merc or some other custom with many hrs of metal work i would blast and spray down with ospho . since it would set raw for many months . once done i would retreat it well then rinse well .
it is tried and true for decades. the rest is a bunch of marketing snake oil imho .

an old indian once told me " what be there when start be there when finished "

if you wouldn't mix it in your paint dont put it on the metal , exception is w&g remover .
 
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