Hi Glenn -

This sets up a situation very much like the thick application of epoxy an
urethane conformal coatings, back in the days of yore (or whenever it was that
I had hair).  The stresses which result from thermal cycling, particularly in
the MIL temp range of things, can produce cracks in glass and ceramic parts.
And you know where it goes from there.

The second thing that can take place is solder fatigue.  If sufficient epoxy
material is under a part, in a manner where it is competing against the solder
termination in a differential expansion situation, then there is a good
possibility that you will encounter cracked solder at some point.

I have also seen a number of these type imbedments, operated at normal office
temperatures that survived for years without problem, including some in a ten
or so year old 8088 based computer I own.

Good luck - Kelly

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