For doing double sided boards using transparencies I made up a jig
from the same thickness PCB material in the shape of an 'L'.
The top and bottom transparencies are glued with paper adhesive to
either side of the jig, and the board to be exposed was sandwiched in
between and butted up against the inside edges of the 'L'. There are
no curvature effects. Maybe this approach could be used with PnP.
Cheers
Stewart
--- In
Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@g...> wrote:
>
> On Mon, 02 Jan 2006 20:34:50 +0100, kennytrussell
> <kenneth.trussell@t...> wrote:
>
> >
> >
> > I have not done double-sided yet. I do have a question for someone
> >
> > about the "pouch". When you slide the board in, how do you assure
> >
> > that both sides of the pouch are still equally positioned? If the
> >
> > paper curvature is different for one side than the other where edge
> >
> > of the board meets the bound side of the pouch, wouldn't you get an
> >
> > ofset? (not sure I explained that well) For single sided boards, I
> >
> > trim my transparency or paper (whichever I am using) to just the
> >
> > outline of the board. Do you keep it a lot larger? Help from all
> >
> > appreciated.
>
>
> Yes, the curvature causes an error for me. If i put in in a
folded-over
> piece of thin cardboard the curve is much more gradual and not a
problem.
>
> ST
>