Flux.  Flux is what is used when soldering copper pipes and is nice to use
when soldering circuits. A lot of solder is 'flux-core' so it is often not
necessary. BUT to clean the copper, you may want to use some plumbing flux
(just dip the end in and scrub. Maybe heat a bit with a torch too). Or if
you have access to some chemicals- Hydrochloric acid (0.01M) will do the
job of cleaning copper, so will muric acid (same thing!) or MAYBE, but i'm
not sure- Acetic Acid- aka Vinegar (but i think vinegar is too weak).

Or just keep scrubbing!
-Matthew

Matthew Pollard          "Racing with the wind and flirting with death
Dept. Of Chemistry        So have a cup of coffee and catch your breath"
University of Idaho
www.uidaho.edu/~poll7356

On Wed, 24 Oct 2001, Laurence Smith wrote:

> I am attacking all my ground wires with a vengence and doing the Ultimate
> Fix #1 on them.
>
> I have discovered that almost all of them in the engine compartment are crap
> and in poor condition.  So now I am SOLDERING new eyelets etc (as per
> Ultimate Fixc #1) on all of them.
>
> Question: All the ground wires have this black oxidation crud on them, even
> when I strip the insulation off.  I've tried cleaning with a wire brush but
> it does a poor job.  Is there a better technique or goop that I can use to
> clean up the copper before soldering?
>
> Thanks.
>
> Laurence Smith
> Hamilton, Ontario
> 90 Westy "Fanumbos"
>