Hey Everybody-

    We are using 96.5/3.5 tin/silver solder paste on our top side and I have
been noticing that on some QFPs the paste forms a heel fillet, a negligible
toe fillet, and does not wick over the top of the lead "foot".  I am
checking to see of the components have a palladium finish (I am pretty sure
they do).  If it turns out they do, is there an issue with tin/silver paste
and palladium coated leads?  We are peaking at 230-235 C (ten zone
convection Conceptronics) so the boards are getting plenty hot.  Why does
the paste seem to bulge up at the toe fillet, but not wick onto the lead
surface?

-Ryan Jennens
TelGen Corporation