Dave try a flanged nut , so that the top layer of lamination is over the
flange, Alternately try cleaned , treated Pems so that the Epoxy flows
and adheres to the pems. That will give you a pull strength equal to the
shear strength of the adhesive system in the prepreg. Also you could try
a high strength epoxy after lamination to bond the insert to the hole
wall.
        A though in closing , If the Pem or some insert has large
threads or other protrusions on the outside then during the flow of the
prepreg it should encapsulate and bond the insert in place. The trick is
to keep the resin out of the treads. A high melting point wax plug is
one way to do that , along with a liberal coating of PVA mold release
        Hope this gives you something else to think about
        Russ
 ----------
From: Dave Curry
To: [log in to unmask]
Subject: [TN] Technologies for blind HW
Date: Friday, July 24, 1998 5:14PM

We have a very unique application that require the use of
4-40 screw to mount a surface mount contactor to the topside
of a PCB board but the HW can not interfere with Surface mount
pads on the opposite side of the board.

The board will use blind/buried via technology. We don't belive that a
PEM inserted in to a blind machined hole will stay in place.

Has anyone seen a technology for inserting hardware before the layer
are laminated?  Any other ideas?

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