That's just great; we get to redesign all the circuit boards in the world in order to be successful at soldering SMT assemblies! No cost involved there that I can see! That should be some more cannon fodder for John and "Push Back"! KennyB -----Original Message----- From: Werner Engelmaier [mailto:[log in to unmask]] Sent: Thursday, November 02, 2006 1:33 PM To: [log in to unmask] Subject: Re: [TN] Bizzare Phenomena... Hi Steve, Tombstoning is worse for LF-solders than for SnPb. The surest way of eliminating tombstoning entirely is by eliminating the fillets--make the pads the same size as the metallization on the CC underside [or just slightly larger]. No more tombstoning, no more CC cracking and more reliable solder joints as well because you wind up with more solder joint height. Werner --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 -----------------------------------------------------