Hi Steve et. al.

        We have used Non-functional pads on a large preponderance of our boards
for many years now. We have proven that there is a greater reliability of the
Plated Through Holes during thermal cycling. This is due to the larger
percentage of copper in the stack, which reduces the overall Z axis expansion
(less polymer in the barrel area). A few of our customers ask for no
non-functional pads and we comply, but the reliability is lowered.

Regards,
Les Connally

>  From: "Stephen R. Gregory" <[log in to unmask]>, on 2/22/99 3:02 PM:
>  In a message dated 2/22/99 11:12:04 AM Pacific Standard Time,
>  [log in to unmask] writes:
>
>  << All,
>
>           Do a lot of board fabricators remove unused pads ?
>
>
>                   Regards,
>
>                   Jerry Schwartz, CID
>                   IPC Certified Interconnect Designer
>                   "May the Schwartz be with you" >>
>
>  Obie-Wan Kanobi...(grin),
>
>       If I may I inquire, what is it that you mean by unused pads? Pads that
>  do
>  not have traces to them? I should hope not! Not without at least talking to
>  the customer, how do they know what's used or not? I've never heard of
>  something like that happening...
>
>      Sounds like Darth Vader has been a little too sloppy with his light
>  saber
>  around there...hehehe
>
>  -Steve Gregory-
>
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