Hi Henry,

As a CM we have a customer that uses press in PEM nuts and it ain't pretty.
The operative word here is "pressing" metal with flutes around it into a
hole in a sheet of glass. Many stresses are induced that are not normally
associated with glass. We get fracturing or crazing around the holes and it
even looks worse after wave solder.

Apparently they have determined that it is acceptable for their application
but I sure don't like the way it looks.

Possibly pressing them into a PTH might be better but we've never done that.
Also I doubt that the holding power of a plated hole would be as good as the
glass.

Best of luck,

KennyB

 
-----Original Message-----
From: henry rekers [mailto:[log in to unmask]] 
Sent: Friday, November 06, 2009 10:55 AM
To: [log in to unmask]
Subject: [TN] PEM (rivets) in PCB

Is anybody out there aware of any spec/inspection criteria/documentation on
how to specify/design/inspect Pem type fasteners?
 
We have a design that may require this, but I'm not willing to commit until
I have some more background info.  Specifically, is this a normal process
for a board shop?  Are there any 'gotcha's'?
 
Thanks.



---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------