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Date: | Tue, 20 Jul 1999 20:21:27 EDT |
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separation at the copper plating knee betwwe the vendors
copper and the plated copper. It reminds me
resin smear between the board's external copper and the plated copper.
Ed
If all you have is as described above, then it probably won't be a problem
since you have the total land surface to make a connection and the land/
foil connection is supported by the laminate in the center of the board
HOWEVER
It is hard to tell if the separation is due to a crack from thermal
stress or whether it is due to smear.
IF YOU DO HAVE A CRACK - it can propagate and you would lose your
connection to the land.
I have seen several cracks in this area because the land area is not
supported
and moves alot when laminated - and the cracks appear. These cracks are
present as received and usually get larger with thermal stress testing.
So it is important to know whether you have a crack or just a separation and
whether
it propagates as a result of thermal stress.
If you had a photo to send, we could take a look and let you know what our
totally
solicited opinions are =
Susan Mansilla
Robisan Lab
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