How many are missing now? I have worked with some boards that were abused in the manner you described and the pads that were still on the board were very weak. I know this because some of the remaining pad pulled off when I lifted the kevlar tape that is part of the thermo-bond process. Would the remaining pads pass the tape pull test for solder mask adhesion? > -----Original Message----- > From: TechNet [mailto:[log in to unmask]]On Behalf Of Francis Sun > Sent: Wednesday, May 08, 2002 4:38 PM > To: [log in to unmask] > Subject: Re: [TN] Guidelines or standards for number of missing unused > BGA pads allowed > > > Mr. Moon, > > Thanks for your interest in my problem. > It is unfortunate, but we are relatively new with BGAs, > and our rework personnel and Engineers are/were not familiar > with the procedures to reduce heat and be gentle when cleaning the solder > from the pads. > Live and learn. > > Hope you or anyone out there can help. > > > Regards; > > Frank Sun > IVHS > (905) 624-3025 ext. 1235 > Fax: (905) 624-4572 > > > |---------+----------------------------> > | | Earl Moon | > | | <[log in to unmask] > | | M> | > | | | > | | 05/08/2002 01:41 | > | | PM | > | | | > |---------+----------------------------> > > >----------------------------------------------------------------- > -------------------------------------------------------------| > | > | > | To: [log in to unmask], Francis Sun > <[log in to unmask]> | > | cc: > | > | Subject: Re: Guidelines or standards for number of > missing unused BGA pads allowed | > > >----------------------------------------------------------------- > -------------------------------------------------------------| > > > > > I'm missing something here? I've never lost a pad during thousands of > rework/repair oparations. > > No disrespect. I just don't get it but am sure you will explain. > > MoonMan > > ------------------------------------------------------------------ > --------------- > Technet Mail List provided as a free service by IPC using LISTSERV 1.8d > 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 delivery of Technet send e-mail to > [log in to unmask]: SET Technet NOMAIL > 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/html/forum.htm for additional > information, or contact Keach Sasamori at [log in to unmask] or > 847-509-9700 ext.5315 > ------------------------------------------------------------------ > --------------- > --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d 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 delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------