Dave, There are notations on the specifications that the latest IPC specs. supercede the old FC specs. There's a paper/document trail. That should be all they need. Dan S. ----- Original Message ----- From: "Dave Connitt" <[log in to unmask]> To: <[log in to unmask]> Sent: Monday, June 22, 2009 2:39 PM Subject: [TN] Flex circuit specifications Hello, We have some flex circuits that were designed to the older IPC-FC specifications and our fabricator is asking us to update our drawings to replace the older specifications with the newer ones. To implement this, we in turn have to ask our customers for permission to change the drawings. In order to do that, we need to get a idea about what was changed or reorganized when the specification was changed. Can anyone give me the two sentence explanation regarding these specifications? Old Specification New Specification IPC-FC-231 IPC-4202 Flexible Dieletrics for use in Flexible Printed Wiring IPC-FC-232 IPC-4203 Specification for adhesive-coated dielectric film for use as cover sheets for Flexible Printed Wiring IPC-FC-241 IPC-4204 Flexible metal clad dielectrics for use in fabrication of Flexible Printed Wiring Thanks, Dave Connitt CID+ Printed Circuit Designer L3 Fuzing & Ordnance Systems A Wholly Owned Subsidiary of: L3 Communications 3975 McMann Road Cincinnati, Ohio 45245 Ph. 513- 943-2010 Fax 513-943-2288 --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------