trace wrinkles

[David Griffith]

On Fri, 6 Jul 2007, Ethan Dicks wrote:

> On 7/6/07, David Griffith <dgriffi at cs.csubak.edu> wrote:
> >
> > I haven't heard anyone discuss this yet: what causes traces on some old
> > PCBs to wrinkle and not others?  My guess is a combination of suboptimal
> > glue and wide temperature swings.
>
> Wrinkles?  Ones I've seen are, AFAIK, solder buildup between the
> copper trace and the solder mask, not between the copper trace and the
> underlying board.  You have something different going on?

Yes, wrinkles.  I see this most often with wider traces.  Commodore 64s
seem especially prone to this.

-- 
David Griffith
dgriffi at cs.csubak.edu

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