Werner,
Too quick a set of fingers hit send before adding cool rate and solder
joint size. You are absolutely right and I sent another post almost
immediately but to restate those additions,  these can be two of the
biggest contributors to wave solder cracking. Heating up is not the issue,
it's when we try to quench a large joint that real problems begin. Solder
joint size and cool down rate are critical.

Thanks again,

John

At 02:26 PM 8/17/01 -0400, you wrote:
>Hi John,
>Your list of factors elating to thermal shock cracking in ceramic capacitors
>is fine, but incomplete. You need to add cooling speed after soldering, too
>rapid cooling also is thermal shock and can cause cracking due to
>differential thermal contraction.
>
>Werner Engelmaier
>
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