Werner Engelmaier wrote:

Hi Earl,
You state that : "running the boards more than once (soldering
operation)
starts to degrade their initial quality and long term reliability."
That simply is not so. What is different between one or two passes that
affects in any measurable way the quality and long term reliability?

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]

 =============================================================================

Hi Werner

An answer to your question in just two words.

        [[[[[[[[[[[[[[[THERMAL STRESS]]]]]]]]]]]]]]]

Hope this helps.

Franklin D Asbell, CQA
Network Circuits, Inc.
Irving, Texas

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