--- In
Homebrew_PCBs@yahoogroups.com, "Andrew" <andrewm1973@...> wrote:
>
> > Steve wrote:
>
> > <snip>
> > I removed -all- the solder right down
> > to the bare copper, then used that
> > electroless tin plate. Cleaned the
> > lead oxide off of the spring contacts
> > in the connector, and the game was
> > golden after that.
>
> Steve - Was the electro-less tin plate
> a particular brand ? The generic stuff
> I used from out big yellow and black
> woolworths stores over here (DSE) was
> shocking for corrosion. It would turn
> grey almost straight away and then
> sometimes almost go black.
I don't recall. I don't even remember where I got it. For fun I plated
several pennies, many years later they look as bright as when I plated
them.
> > <snip and out of order>
> > that solder is a terrible thing on edge
> > connectors. The lead surface oxidizes
> > very fast and causes terrible connection
> > problems.
>
> Agree - any thickness of solder is very
> bad for connectors. Thats why I advocate
> wicking the solder up. I suspect that it
> only leaves what tin/lead has alloyed with
> copper when doing a good wicking. Though
> I may be speaking carp here and it might
> leave a much thicker layer of tin/lead
> that has not alloyed with copper. In any
> case it is more reliable than a thick
> layer.
No idea. Perhaps when the lead is in alloy with the copper it doesn't
oxidize, but then again it will oxidize when alloyed with tin. Maybe
there is so little lead left, it leaves very little oxidized lead left.
Steve Greenfield