4th board 99.9% perfect - thanks for the input!
2003-01-01 by ghidera2000 <ghidera2000@yahoo.com>
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.