Hello Cara,

Yes some other factors cause blow-holes... One that is more common then
entrapped moisture is Poor Plating Quality.

In simple terms: Folds, voids, thin copper plating and extreme wicking may
help trap more moisture and other chemicals inside the holes. when these go
through high temperature process, some gas is released then causing
blow-holes. It can also be a source of concern for reliability.
Microsectionning is the best way to confirm this problem.

Alain Savard, B.Sc.
Chemical Process Analyst
CAE Electronics Ltd.
e-mail: [log in to unmask]


-----Original Message-----
From: Cara.Startek [mailto:[log in to unmask]]
Sent: August 9, 2000 2:52 PM
To: [log in to unmask]
Subject: [TN] Blow Holes

I'm having a problem with blow holes occurring in a thick board that I'm
running on a wave solder machine.  As a test I am going to bake the boards
for 24hrs to remove moisture from the board and eliminate this as a cause of
the problem.  Is there any thing else that cold be causing blow holes?

Cara Startek

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