Earl,

What you could be seeing IMHO is the result of an ancient technique for wave soldering called wax stabilizing. Essentially, the through-hole components were run through a wax wave to hold them in place during in-line lead trimming prior to entering the solder wave. Many times a joint was contaminated and not the most reliable thing on the planet, but "it passed test... ship it!" was the common mentality, and now you see why we don't do that anymore. I don't think a reflow would resolve the issue at hand, since we would still have contaminated surfaces.

Just my "dos centavos" from an old guy that remembers stuff.

Regards,

Ed Popielarski
QTA Machine
10 Mc Laren, Ste D
Irvine, Ca. 92618

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Fax: 949-581-2448
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