Anna- That's a very high stress point, and there are a whole bunch of factors which come into account. Obviously, you can place some stiff RTV at that point to make the bend radius larger. Hot melt glue might work for some apps. This can be a sloppy process and adds time. Alternatively, you can introduce a separate forming process, which bends the flex section as a very controlled process. Following this the assembly would be placed in a fixture to prevent inadvertent extra bending during assembly. The circuit board production process can also probably be re-engineered to improve the crack resistance of the conductors. For example, is the metal on the flex Rolled Annealed? Is the roll direction controlled to be in line with the conductors? How thick is the metal? Can the dielectric within the flex layer be increased in thickness to help control the bend radius? Can the metal thickness on the flex be reduced to make it less likely to crack? Is the metal on the flex electro-plated during the manufacturing process (this vastly reduces crack resistance)? I have seen most products move from rigid/flex constructions to separate rigid and flex boards. This is made possible because of cheap, dependable flex connectors which mount on the rigid boards. With independent flex construction its a lot easier to control stiffness as well as problems with the assembly process. Wayne Thayer >>> [log in to unmask] 2/22/2007 6:55:25 am >>> Hello Techneters, We have some boards disconnected in transition zone: between rigid and flex segments. This happens during an assembly process. What is recommended to add to manufacture process in order to strengthen the area. Thank you, Anna Seredovaya Kodak IL Ltd. --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------