Phosphoric Acid for rust cleaning / inhibitor: Mixture and Procedure

[jellycatsdad]

I use Ospho, it is pretty much a standard in the marine industry.

Ospho

I’ve used it on the exterior of my tanks over the hydro stamp before Rust-Oleum. Is it safe for the insides too?

 

[rjack321]

I’ve used it on the exterior of my tanks over the hydro stamp before Rust-Oleum. Is it safe for the insides too?

It's fine. It's basically just an acid so once it's drained and dried there's nothing left to volatilize

 

[happy-diver]

https://www.global-mfg.com/Downloads/SDS-GSMoT-Acidic-Tank-Cleaner-42070-version-2.pdf

 

[lexvil]

It is like parkerizing the tanks

 

[flymolo]

would you consider a tank "clean" for oxygen after using this? Or do you take extra steps like using detergent

 

[stretchthepenn]

would you consider a tank "clean" for oxygen after using this? Or do you take extra steps like using detergent

The tank would Definitely Not be oxygen-clean after an acid-wash. You'd need to follow the standard oxygen-cleaning procedure afterward.

 

[grantmac]

The tank would Definitely Not be oxygen-clean after an acid-wash. You'd need to follow the standard oxygen-cleaning procedure afterward.

I'd be curious to hear your logic behind this?

 

[rjack321]

The tank would Definitely Not be oxygen-clean after an acid-wash. You'd need to follow the standard oxygen-cleaning procedure afterward.

Based on what? There is nothing oxidizable in a phosphoric acid wash.

 

[stretchthepenn]

I'd be curious to hear your logic behind this?

Based on what? There is nothing oxidizable in a phosphoric acid wash.

Maybe I'm wrong, then. But I can't see that doing an acid wash and then saying "good enough, fill 'er up with oxygen!" would be a good idea. Would you do that?

 

[rjack321]

Maybe I'm wrong, then. But I can't see that doing an acid wash and then saying "good enough, fill 'er up with oxygen!" would be a good idea. Would you do that?

Because 1) there is nothing organic that can oxidize in phosphoric acid, the steel itself is more likely to combust than phosphoric acid "residue" (hint there isn't any) and 2) if you go re-washing it after your acid wash...

you are that much more likely to just reflash rust the interior which kind of negates the whole point of the acid wash in the first place. So yes, I wash with simple green to remove any oils, swap to phosphoric acid, rinse and dry it. Its perfect that way