I know the IPC spec. for bow and twist is 0.75% on a PCB but what about a PCBA? Is the spec the same? If there is no spec is there a rule of thumb? I have a 12"x4" 0.062" FR4 PCBA with a bow in it that I need to determine if it is within industry standards. I need to know what to put into our worst case mechanical stress model. Thank you in advance. Best Regards, Mike Forrester LeCroy Corporation --------------------------------------------------- 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 -----------------------------------------------------