Now that we've got the pad thing cleared up, there's a little matter of pad
shape and paste overprint to consider. Not being a guru myself, I just
experimented and got a few tips from folks like HP (Carla F. - is that her
name?) who personally got me on the right track to .8 mm stuff. Beyond that,
everyone's helped me.

Overprinting solder paste, as you really have to use it no matter the
consequences, is a good thing. It ensures, now that you've made your pads
smaller, that an adequate paste volume is present for reflow. I can tell you
more about this, but so can most everyone else on this forum.

Square pads? I never used them though many have and swear by their
capability to promote better solder joints without shorting. Again, never
used them so don't really know. Again, BGA's ain't no big deal. Reworking
them can be so watch out for some interesting things as dogbone traces not
going straight from point A to B. If you make them at right angles, shorting
can be an issue. And on it goes but remember, as that guy from NH (what was
his name and where is he now?) always says: "BGA's ain't no big deal."

MoonMan


Oh yes, printing flux instead of paste is the way to go if you could figure
out a way to do that.

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