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Subject: Low leakage coatings? Re: how can i prevent corosion?

From: "Steve" <alienrelics@...>
Date: 2003-12-02

--- In Homebrew_PCBs@yahoogroups.com, Russell Shaw <rjshaw@i...> wrote:
> Steve wrote:
> > --- In Homebrew_PCBs@yahoogroups.com, Russell Shaw <rjshaw@i...>
wrote:
> >
> >>Why do you need ∗any∗ coating on the pcb?
> >
> > Exposed conductors mean they are exposed to humid or dusty air, and
> > the surface of the fiberglass substrate will build up contaminants and
> > humidity.
>
> You could put the pcb in a sealed container with dry nitrogen
> or normal air with moisture-absorbing gel.

I was hoping for something that would allow repair and that would not
require hermetically sealed pressure tested enclosures. Otherwise
those are not bad suggestions.

If you are wondering why I say pressure tested, the first time it
ships by air it's got to stand more than a few PSI. That means a lid
2x4 inches at, say, 10psi air pressure in an unpressurized hold has to
stand up to about 36 pounds forcing it open. I'm just shy of sea level.

Steve