Where does the cracking occur?
What tolerance do you spec on the .006 finished hole diameter?
What type of gold finish are you specifying?
Without knowing the full history, I would suspect that the connector holes are
too small . Have you measured the finished hole diameters?

Scott Buscomb

>
> 1. The spec sheet for the connectors call for a drill of 0.007in with a
> finished size of 0.006in Does the use of gold mean a thinner finish and
> perhaps the fab shop are drilling smaller to accommodate this and
> subsequently cause the pin of the connector to try and cut through the
> board material rather than swage through the metal ?

>
>
> 2.As the gold finish is harder than tin lead would this cause insertion
> forces to increase to the extent that the board could crack?
>
> 3.This is one for the assemblers out there. Do you measure the insertion
> force when fitting press fit devices?
>
> 4.Not wanting to forget the chemists. The material the fab house is using
> has an Er of 3.8 does this mean more epoxy less glass and possibly more
> prone to cracking.
>
> 5.What finish are other people specifying for this kind of assembly?
>
> 6.Finally,I have also heard of possible reliability issues when press fit
> connectors are combined with gold finish. What they, if any, and how do I
> deal with them.
>
> Sorry once again for the long list, but it's kinda worrying, sitting here
> looking at a potential 20000 dollar pile of scrap.. oh happy days
>
> Cheers
>         Gene
>
> Gene Holmes
> HCD Ltd
> www.hcduk.com