Franklin, If you are referring to welding repair ribbons to inner layer circuit traces, IPC-2012 states that weld repairs are not acceptable without prior approval by the customer. I am not aware of any published reliability data. Perhaps someone else knows of some studies. Don Vischulis -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of Franklin D Asbell Sent: Thursday, October 03, 2002 12:39 PM To: [log in to unmask] Subject: [TN] Question regarding welds I'll try sending this for the third time...hmmm... Was wondering if there are specifications, standards, requirements, etc regarding the welding of innerlayers??? Is this an acceptable practice? Are there any data on reliability studies available anywhere? And any of your personal comments/opinions would be appreciated also...thanks Franklin D Asbell ---------------------------------------------------------------------------- ----- Technet Mail List provided as a free 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/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 1.8e 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------