hello Jim, Quick thought for flex... Use .002 1/1 or half over half adhesiveless Use .001 cover coat (Polyimide Kapton) Termination of cover coat .025-.075 at rigid junction requires this area to be via free for .10 inch... thats a tuff one I know Traces only perpendicularly transition rigid flex Traces only perpendicularly transition rigid flex Relieved planes in flex are very nice for flexing No adhesive between flex pairs Either epoxy or poly rigid works complex flex will require preheat and a fixture after assembly for shape forming If your doing FR4 flex things are different I love flex Boston Brad --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d 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 delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 ---------------------------------------------------------------------------------