Dear Ted Tontis,

Ted Tontis <[log in to unmask]> on 2001-06-14 12:15:59 PM further clarified:
>        isn't the crosshatching on the outer layers primarily used to avoid
>blistering?

Every FR4 board I've done for the past 2 years has had a big (covering roughly
1/8 the entire board) solid (not cross-hatched) polygon on an outer layer
(opposite the component side). I haven't heard of any problems with it. Over 5
years ago, I saw some boards with ugly-looking wrinkles in the green solder mask
over solid copper areas. It was merely a cosmetic blemish, it didn't affect
functionality -- but even that doesn't happen with modern LPI solder mask. There
is no longer any reason to do crosshatching.

>A sold plane (large plane >2mm) would hold the heat from the
>reflow process, or wave, and possibly damage the sub straight?
>
>Ted

That's not a problem. Check out page...
[Flips through reference book] I thought I could turn right to the page that
explained proper ``copper balancing'', but I can't seem to find it just now.
Does anyone know a web page or some other reference to explain proper ``copper
balancing'' ? Maybe I've just been lucky in this area.

--
David Cary

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