Bob, As long as the laminate isn't cracked under other pads (as a result of the board handling/service), then it should be OK if you "glue down" just one pad. Vladimir -----Original Message----- From: TechNet To: [log in to unmask] Sent: Fri Nov 17 12:37:06 2006 Subject: Re: [TN] One solder Ball Not Connected on a No Connect Pad After Rework All: Thanks for your responses. One of the weaknesses of this forum is the lack of ability to load photos and movies into the thread to explain the case with pictures whihc are worth much more than words in these cases. Perhaps I should explain the repair more thoroughly. We are suggesting to this customer (Class II, consumer grade product) that we "cut off" the pad and epoxy down any remnant pad. This is much less expensive Amercian labor than doing a complete IPC 7721 repair. The real issue that I am asking for input from the esteemed group on is the pull strength..... Thanks Bob "Stadem, Richard D." <[log in to unmask]> wrote: When the pad is lifted, it typically exposes the fiberglass weave underneath the pad. This allows moisture, flux, solvents, etc, to enter the pwb and can cause problems later. The answer to your question depends on what the assembly is used for, and to what standard do you wish to comply with. IPC 610 and J-STD-001 do not allow missing pads, they require it be repaired. -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of bob wettermann Sent: Friday, November 17, 2006 9:11 AM To: [log in to unmask] Subject: [TN] One solder Ball Not Connected on a No Connect Pad After Rework This question to the group is about expected solder joint strength on a BGA. The BGA in question is a 8 x 8mm plastic package BGA using a LF SAC305 soldering process. It has 64 x 0.018" balls holding it to the PCB. When removing this device for rework 3-4% of the time one of the corner NO CONNECT pads comes off. The question is if we do nothing upon replacement of a new device to the damaged pad will it really make a difference ??? We are arguing that the holding strength of the reworked device would be approximately the same because the change in overall surface area is marginally impacted. Thanks Bob Wettermann Bob Wettermann --------------------------------------------------- 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 ----------------------------------------------------- PH 847-767-5745 --------------------------------------------------- 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 ----------------------------------------------------- Bob Wettermann --------------------------------------------------- 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 ----------------------------------------------------- PH 847-767-5745