Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

My third board was a flop. My plexi weight had a slight curve in it
and I didn't notice - lost the traces in the center during
development. For the fourth I used the curve to my advantage and
propped up the sides with my first two (discarded) boards.

I also changed from the MG boards to a different brand. No choice,
store didn't have MG. This one claimed 60 second exposure with a UV
source and 6-8 minutes with a florescent. I thought my UV florescent
would qualify as a UV source - it doesn't (silly me :D) Exposed for
60 seconds and tossed it into the developer. Sat there for two
minutes with zero effect. I rinsed it off and re-exposed for 6
minutes (board is gone, may as well experiment). Developed in like 1
minute and it was PERFECT. Couldn't believe it. I expected to see a
ghost of the first exposure but there was none at all.

Tossed it into the etcher and it came out almost perfect. No shorts
at all despite using a bunch of 1.2 mil traces spaced 25 mil apart
(center to center). There is one trace that has a tiny spot which is
about half the width its supposed to be. Can barely see it with the
naked eye (I'll hit it with a tiny dab of conductive pen). I'm
thinking I probably lost a bit of resist during the first developer
foray. Hopefully my circuits are correct and this one works. They
work fine on the breadboard and I looked them over (and over, and
over) before I even did the first printing. If it does then I have a
week or two of schematics and breadboarding before I etch my pH and
ORP controller for my swimming pool.