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Date: | Mon, 03 Mar 97 07:16:15 PST |
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Do not panic.
Depending on the solder mask and your wave soldering conditions (flux
etc.) this might be normal for the solder mask in question and
although not desirable, it might be acceptable. What I mean by
acceptable is that the performance properties of the solder mask was
not compromised. The condition, for example, could only be a surface
attack and has discolored the mask.
More research needs to be done. You should call the solder mask or
Board Fab. Manufacturer to take a look at the boards and the wave
soldering parameters.
Hope this helps
______________________________ Reply Separator _________________________________
Subject: Soldermask question
Author: [log in to unmask] at corp
Date: 2/28/97 2:22 PM
We are just beginning to use soldermask on our PC boards. We are
specifying liquid or dry s/m over bare copper (no surface mount). Our
assembly group is also new at inspecting soldermask boards. They have
seen on one part (from another division) where the soldermask changes
visually after wave solder. It changes from a 'glossy' look to a 'dull'
or 'etched' look. They are unsure if this is a problem.
I have looked thru the ANSI/IPC-SM-840B for any information about this,
but have found none. Have any of you experienced a similar situation
with soldermask? I do not know the type of mask, the vendor, or
anything else about the board in question (I've asked our assembly group
to see if they can get this info). I just want to make sure to specify
the right thing on my drawings without limiting our board vendor(s) too
much and calm any fears of our inspectors.
Thanks for any help...
Ben Davis
Systems & Electronics, Inc.
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