My biggest problem was screen printing.  I had typically used 8 mil thick 
stencils for 50 and 25 mil work.  I reduced to 6 mil thick, apertures full 
size - oblong shape (ie. rounded ends).  I also had to switch to a finer 
mesh solder paste.  -325+500 is the new mesh size.  We had beed using 
-200+325.  Once we got the screen printing down, it was business as usual.

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Hello,
Our design requirements are driving us to finer pitch technologies.  We 
currently assemble 50mil pitch devices.  My expectation is that our next  
generation of products will be 20 to 25 mil pitch.  I am interested in 
hearing war stories of people who have been through this process.  
Specifically, what was the number one problem encountered and how was it 
overcome?
Thanks

Mitch Austin
Itron
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Patrick McGuine
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