I'm sure I know less than Mike's forgot about chemistry, but here's an idea.
What if "neutralize: in this context doesn't mean "to make the ph 7.0" and
instead means to stop the effect of that particular acid, so that you can
paint over it? Just because vinegar is acidic doesn't mean it will do the
same thing as phosphoric acid does it? And maybe the best base (no pun
intended) to paint on actually is acidic?
Revealing my stupidity,
<dnw>
1972 Midget
1998 Safari
1999 9-3
1964 (Me)
----- Original Message -----
From "Gerard" <pixelsmith at gerardsgarage.com>
To: <spridgets@autox.team.net>
Sent: Wednesday, December 19, 2001 2:56 PM
Subject: Re: painting advice wanted- acetic acid?
> >> Forgot to include: Vinegar is to neutralize the acid and should be
> >> flushed, dried and scuffed before painting. phosphate coating will
> >> retard rusting but is not a long term fix.
>
> ---->> Bruce Lowry
>
>
> >
> >
> >This is slightly off topic, but I'm curious what the vinegar is for. I
> >teach chemistry to UNC students and so it strikes me as odd that you
would
> >treat phosphoric acid with acetic acid (~5% or so in water makes vinegar)
to
> >neutralize it. I tell our sophomores and freshman that you neutralize
> >(carefully) an acid with a base (caustic, sodium hydroxide, etc), not
with
> >another acid (they lose points for that <gr>).
>
>
> Mike,
>
> You got me? This struck me as odd too. I always thought you neutralize an
> acid with a base too. This was Bruce Lowry's suggestion. If it's someting
> I'm going to paint right away, I ususally just rinse in water and dry
> quickly, then scuff with a red Scotchbrite, blow with compressed air and
> paint. Small parts that I soak I will also rinse in water and towel dry.
> Before they go into use I will wire wheel them and usually paint them.
>
>
> >
> >However since acetic acid is more volatile than phosphoric acid (the
smell
> >of vinegar), maybe it is there to simply replace the non volatile acid
for a
> >more volatile one. Thus effectively neutralizing the surface (after
> >drying).
> >
> >Does this make any sense, or am I once again missing something.
> >
> >Prof. Mike
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