I'm needing information on PCB's with silver finish. We are using HASL but having problems with our proto fab shop. They have a very hard time keeping the HASL somewhat smooth on the fine pitch parts. They sent us a board with silver finish and we ran it using our same process. Appeared to make a pretty good solder connection, just not as much solder on the pads now without the extra solder from the HASL. Are there special requirements on which paste I should use.. Will I have to use a thicker stencil... What is the shelf life before it tarnishes and can you solder if it is tarnished.
The information will be appreciated....