I would have thought that your first problem would be that the flex will be flat when manufactured and will therefore wrinkle when bonded to the curved surface unless the curvature is very slight. I'm assuming a doubly curved surface, obviously you won't have that problem if the curvature is along only one axis. This sounds like the kind of thing that you could assemble using a "vac bag" process in the same way as composite structures are made. The main issue with vac bag as I understand it that of movement between the layer that are being laminated together. I guess this could be avoided by designing in self jigging features to the mating parts. You may wish to consider sub contracting the job to a manufacturer of aerospace composite components?? Sounds like an interesting challenge. Sorry I can't be of more help. Regards, Stadem, Richard D. wrote: > Perhaps you can use a film adhesive such as Ablestik. > > -----Original Message----- > From: TechNet [mailto:[log in to unmask]] On Behalf Of Brian Chandler > Sent: Thursday, April 03, 2008 6:46 AM > To: [log in to unmask] > Subject: Re: [TN] Vacuum Assembly > > My apologies for not defining the issue clearly. > > The issue is, we are looking at laminating a flex circuit to a concave > surface. > The flex will have capacitive switches on it so voids between the flex > and the concave surface will cause degraded performance of the switch. > We need to avoid air bubbles between the flex and the mating surface. > > The opposite side of the concave surface is a TALC surface, so no > scratches or blemishes can be tolerated. > > Thanks for the feedback already provided. > > -- Eric Christison Msc Mechanical Engineer Consumer & Micro group Imaging Division STMicroelectronics (R&D) Ltd 33 Pinkhill Edinburgh EH12 7BF United Kingdom Tel: +44 (0)131 336 6165 Fax: + 44 (0)131 336 6001 --------------------------------------------------- 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 -----------------------------------------------------