I would like to add to my comments in the last E-mail.

The reduction from 7 thou to 6 thou stencil thickness will of course reduce
the incidence of blocked apertures where the paste is held inside after
release. The change in aspect ratio due to reducing the thickness is an
approach. But the aspect ratio can be tackled by another approach. The
length of the pads and therfore the length of the printed strips possible
can be increased. If the printed strips are sufficient then the amount of
adhesion of the paste to the pads will be greater than the adhesion to the
inner wall. I personally feel 70 thou pads are the minimum length suitable
for fine pitch. At 7 thou thickness 55 to 60 thou pads do yield blocked
apertures and therefore unsoldered leads.
This of course is dependant on the paste also. Many modern pastes have
brilliant printing characteristics and will go through almost any aperture.
So consider the abilitiy of your paste. What about the condition of your
paste? Has it dried out after time?

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