Peter, I scanned the msgs quickly and didn't see a reply if there was one. IPC-6012 Qualification and Performance Specification for Rigid Printed Boards clause 3.4.4 "The printed board shall have a maximum bow and twist of 0.75% for boards that use surface mount components and 1.5% for all other boards." >>> "Phillips, Peter (NM75)" <[log in to unmask]> 09/03/99 01:41PM >>> Age old question with new requirements- Where can I find the recommended accept/reject warp and twist criteria for PCBs used for BGAs? ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ############################################################## ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################