Jeff,

The soldermask in question could be under cured or the board could have
been improperly cleaned prior to soldermasking.  The standard test for
soldermask adhesion is a tape test described in IPC test method
2.4.28.1.  This is the test used for both commercial product and
military product.  A copy of this is in IPC-A-600E.  Also paragraph
2.9.5 (p. 36) of IPC-A-600E defines the amount of soldermask allowed to
lift (depending on the surface it is applied to) for each class of
board.

Jay Soderberg
QA Engineer

Legal Notice:  All opinions are mine and mine alone.  The opinions
expressed do not necessarily reflect the opinions of the management or
ownership of this station.



>    ----------------------------------------------------------------
>
> Subject: solder mask (LPI) flaking
> Date: Wed, 30 Sep 1998 11:40:32 -0500
> From: Jeff Hempton <[log in to unmask]>
>
>      Fellow Technetters,
>        On some of our bare boards before build, with normal board
> handling,
>      (before ANY processing has been done) we are noticing that the
> solder
>      mask is flaking off. This condition is no longer there after wave
>      solder. Our impression is that the mask is not fully cured. Are
> there
>      other things that could cause this (contamination)?
>        Is there a test that we can perform on the bare boards to
> prove/test
>      this?
>      Any thoughts would be appreciated!!
>       Thanx in advance, group!
>
>      Jeff Hempton
>      Sr. Mfg. Eng'r
>      United Technologies Electronic Controls
>      email: [log in to unmask]
>
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>