Lisa Williams wrote:
>  "I would like to get any information that you have to offer concerning
> broach type pemnut fasteners in FR4 material. Normally in our designs we
> try not to use pemnuts in multilayer boards because of the damage they
> can do to internal layers. We have a recent design that does use pemnuts
> and would like to know of any concerns there might be, especially any
> spacing requirement in internal layers.

I'm glad you asked that question, because it reminded me of something I was 
told that I have never heard repeated by anyone else. It was:

"Swaged components most frequently break connections on the SECOND layer 
from the direction of entry. The first layer has enough flexibility, and 
layers past the second have enough support to not get too damaged". 

Since then I have always tried to pay attention to how swaged components 
are connected (even though the statement could be bogus), but I sure would 
like to hear from some experts out there. 
In fact, at one company we were required to tie the swaged hole to vias 
which had thermal relief connections to planes, instead of having a thermal 
on the swaged hole itself.

Can anyone comment on either of these two points?

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