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Subject: Re: [Homebrew_PCBs] Board status in flux

From: "Leon Heller" <leon_heller@...>
Date: 2003-08-24

>From: "ghidera2000" <ghidera2000@...>
>Reply-To: Homebrew_PCBs@yahoogroups.com
>To: Homebrew_PCBs@yahoogroups.com
>Subject: [Homebrew_PCBs] Board status in flux
>Date: Sun, 24 Aug 2003 15:54:34 -0000
>
>Just made another double sided board with 10 mil traces. Quite a few
>traces run between dip pins.
>
>Anyway, I solder it all up, stick my DC ammeter on and power it up.
>150mA on a board that should take 6mA. I went looking for shorts
>with my trusty razor knife - couldn't see any but I did some
>scraping in really close spots anyway.
>
>Still 50mA... Spend two hours desoldering, inspecting and re-
>soldering, check and still 30mA. What the heck is going on I say to
>myself!
>
>After another hour of farting around, I came to the conclusion that
>my flux is conductive! Using a rosin flux remover pen and some paper
>(to soak the sludge up) I cleaned out the tightest spots and down go
>the mAs to 10. Ran out of my spray on cleaner and its sunday of
>course, no electronics suppliers open around here.
>
>Looking at my flux container, I relized I'd grabbed my plumbing flux
>instead - Oatay #5. I never realized that plumbing flux was so much
>different from electronics flux. Lesson learned!


I think plumbing flux contains zinc chloride, which is quite conductive.
You'd have had serious corrosion problems if you had left it on.

Leon
--
Leon Heller, G1HSM Tel: +44 1424 423947
Email:leon_heller@...
My web page: http://www.geocities.com/leon_heller

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