A bit of a wild guess. How are you storing the material? Could there be a
humidity problem
in your short term storage? I would imagine that HASL would highlight any
moisture problems.
Phil.
At 15:25 19/08/99 -0500, you wrote:
> Here's one for you guys, and gal's. We are witnessing measling in
>sporadic fashion. It usually occurs along the edge of the panel,
>sometimes encroaching on the boards, sometimes not. We have already
>contacted our supplier, for their huh hum, expertise. We pulled and
>reviewed again, all process records. There has been no change in the
>process. Verification and calibration records reflect proper equipment
>function. This is happening with 7629 pre-preg in 12 x 18 and 18 x 24
>sizes We had pulled the material with the same lot number, the problem
>went away just as quick. Well, it repeated itself a week or two later,
>again we switched to a different batch of material, the problem went away.
> With the supplier on-hand, we laid up a book using pre-preg from the
>batch we had earlier observed measling from, as well as from another
>batch, there were not any measles observed, we repeated this, and again
>there were measles. We went back to the process, re-checked everything,
>still no significant changes. Our supplier has been in-house for three
>days running experiment's, they even brought someone in to assist him,
>they are just as puzzled. Samples have been sent to Microtek Labs for
>their analysis/opinion, no response so far. Just wondering, does anyone
>out there want to take a shot at this one. Thanks, Franklin D Asbell
===============================================================
Phil Dutton C.I.D.
Senior CAD Technician
IPC Certified Interconnect Designer
Vision Abell Pty Ltd
Second Avenue, Technology Park,
Mawson Lakes. SOUTH AUSTRALIA 5095
Phone : (08) 8300 4400 (reception)
(08) 8300 4481 (direct)
Fax : (08) 8349 7420
email: [log in to unmask]
Internet Page: http://www.vsl.com.au
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