There's an interesting article that sort of talks to your question in
Fridays SMT.

http://urltea.com/5vu 

KennyB

-----Original Message-----
From: TechNet [mailto:[log in to unmask]]On Behalf Of Hfjord
Sent: Monday, April 16, 2007 12:54 PM
To: [log in to unmask]
Subject: [TN] Placement of large flatpacks and BGAs close to board edge


Dear collegues,

I have heard of a thumb rule, never place them along and close to the
edge. Hence, we place them (when suitable) in the center. I have
forgotten why this rule. Was it because of vibration nodes, warpage
during soldering, tempcycle issues or what? Is there a IPC standard or
other reference?

Inge

---------------------------------------------------
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
-----------------------------------------------------