Homebrew PCBs

On Fri, Apr 2, 2010 at 5:57 PM, Russell Shaw <rjshaw@...> wrote:

> Chris Maness wrote:
> > I made up a board on a CAD transfer program, and printed it off on a
> > transparency.  I exposed it to my homebrew UV LED array for 1'30" and
> > transferred it to a store baught developer.  I agitated it in the
> developer
> > at the recommended 10:1 concentration for well over 5 minutes and the
> light
> > sensitive coating showed no sign of coming off.  I exposed it again for a
> > solid 5 minutes, and again put it in the developer with no sign of any
> > action.  I have left in the back yard now to see if it will finally come
> > off.  It does look like some milky looking material is slowly coming off,
> > but this is MUCH longer than I expected.  I am asuming all the positive
> > boards require the same NaOH solution, so I don't think that's the
> problem,
> > but I am not sure.
>
> Positive resist or negative?
>

I'm an idiot.  I did not realize that there is a sticker covering the
sensitive side.  However, after developing, my traces look a little on the
thin side.  Maybe my masque was not dark enough, or I over exposed.  I ran
1m30s, using 15 LEDs on a 4x5 perf board.

Regards,
Chris Maness


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