>
> --- In Homebrew_PCBs@yahoogroups.com, Chris Maness <chris@...> wrote:
> >
> > What is the minimum pad size (in mils) for home made PC boards? (Single
> > Sided).
> >
> > Thanks,
> > Chris Maness
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
> I drill the holes first then laminate dry film resist. UV expose with a
> film negative, develop the image, etch and strip the photo resist. The
> copper pad is never stressed this way and very small annular rings are
> possible. The only problem will be the weak copper adhesion with such a
> small copper area. Any component movement and the copper bond will break.
> With all of that in mind, it's best to use a larger annular ring on single
> sided boards. Most of my designs are surface mount and single sided but any
> through holes are allowed at least .020" around the hole and more if
> possible.
>
>
I was able to adjust my lands in the CAD drawing. They are all beefy now.
80mils, and the inner hole is 30mils. These should be OK. I will be
experimenting more later.
Chris
[Non-text portions of this message have been removed]