><<Has anybody found a functional defect in multilayer pwb's due to
>nailheading???>>
>
>Hello-
>PCB design falls into my design requirements, but I'm not very knowledgeable
>about them...
>
>could you pls define what nailheading is to me?
>
>Thanks in advance...
>
>Regards-
>Brad Martin


Nailheading is a condition where, at the interface of the inner layer of a
multilayer pwb and the drilled hole wall, there is a deformation of the
thickness of the internal copper layer. Usually expressed as a percentage of
the original copper foil thickness, a copper deformation greater than 150%
has been generally considered "rejectable".

hope this helps...

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