Quote Originally Posted by dragons_fire View Post
first one, an old board from about 2 years ago, made with a sharpie marker.. PIC16F84A robot controller
Lots of fingerprints...gotta clean those boards good before you etch. Pretty nice for a sharpie.

second one, a board i made about 6 months ago using a presensitized board and on overhead transparency.... GPS interface for robot
Lots of extra flux, but no fingerprints I can see. And again, pretty good. 90 degree corners aren't the best though once you start dealing with higher frequencies.

third one, the one for this robot, using the toner transfer method...
Get some rubbing alcohol and those soft acid brushes ( http://www.tecratools.com/pages/asso...ics/15215l.gif ) to break down and clean off the excess flux when you're done soldering. That stuff will harden up over time and eat away at everything, as well as possibly cause high resistance shorts (low resistance opens? ) over time. In that class I mentioned, they stressed to go ahead and use loads and loads of flux while you're soldering, but also to clean the heck out of it when you're done.