Hi Frank,
Your possible problems are twofold:
(1) the 'laminate cracks' are actually for the most part separations of the
epoxy from the glass fibers. These separations can cause the growth of CAF
(conductive anodic filaments) to adjacent PTHs, with the result of shorts.
Fires as the result of this have been experienced in the past.
(2) the 'laminate cracks' cause significant non-uniformity in the copper
plating of the PTHs. these non-uniformities are stress risers and can cause
the failure of your PTHs by barrel cracking.

Werner Engelmaier
Engelmaier Associates, L.C.
Electronic Packaging, Interconnection and Reliability Consulting
7 Jasmine Run
Ormond Beach, FL  32174  USA
Phone: 904-437-8747, Fax: 904-437-8737
E-mail: [log in to unmask]

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