Dave, to answer your questions, point-by-point:
� Just out of curiosity, how are second side, skippy components oriented on the board with respect to the wave?
The SMD's are all oriented in the "correct" direction with respect to wave direction(i.e. solder connections on a part touch the waves at the same time).
� Just out of curiosity, how are second side, skippy components separated from other components?
There's lots of real-estate on the bottom side; hence, all components are nice distances apart from each other, and there's no higher-profile parts in front of lower ones. The skippy components are the ones where there's no thermal relief provided.
� What criteria are you using to judge these solder connections? Like is the fillet smooth, showing good wetting, and flowed greater than 25% up the component termination? Er something like that?
For the most part, we use IPC-class ii workmanship standards. When i say "skips", I mean there's no solder there what-so-ever.
...and lastly, I haven't tried solder @45deg. yet. You do bring up good points on your first bullet, though, where you say,
"solid fill ground planes are (1) bad practice, because they create unbalanced construction, in addition to the process problems you state and (2) are usually not required, but designers don�t take the time to determine their radiation and design a grid based on actual radiation. "
I forgot to mention also that these skippy parts are ALL 0603 componentry. We DON't get skips on the 1206's. My original theory with this was that the pads on the 0603's are a problem because 1.) there's not enough darn pad to solder to, and 2.) the flux burns off at a faster rate. On a positive note, the next rev., there'll be ALL 1206's.
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