Thanks for your insights Tom. Some of our EE's here thought they could save money by incorporating all the interconnections between the main board and a group of panel mounted connectors and any other groups of connections that would go between boards and other remotely mounted cards in the unit with rigid-flex technology that otherwise could be solved with a standard ribbon cable with connectors. There really isn't a tight constraint on the room in the enclosure... the only thing we would be eliminating is the cables and connectors... I stacked up the cost of the single rigid-flex assembly verses a group of rigid boards and cables and connectors... the latter was much less expensive. The quantities projected for the product are in the range of a 1000 units a year give or take a few hundred... Let's say I can build the bare board in rigid form without the flex for 100 dollars, if I used the rigid flex approach it cost me 1,000. Granted I save the cost of a couple cables and connectors but they amount to about 20 dollars cost... Somehow that just doesn't make economic sense... In this case anyway... and I got multiple quotes, but yes they were all in the U.S. I'm pondering 'what if' we used flex jumpers and stiffeners that solder to the pins on the panel mounted connectors on the back panel and then use FFC connectors on the rigid board... Do you suppose there are better cost breaks going that way as opposed to incorporating the whole mess into a single rigid-flex board? http://www.imperial-connect.com/products/ffcconn/05A02.pdf Also are we need to ask 'are we using techniques that make the board too expensive?' 'Is cable replacement a bad application for rigid flex?' I can't envision going to China for a 1000 units a year... It seems from your comments that 10:1 costs are inherent in the technology. I'm a little frustrated with this at the moment... Thanks though very much for your insights... :) Perhaps there are others with more points to add that I can consider in approaching this problem as well... Best regards, Bill Brooks PCB Design Engineer, C.I.D.+ Tel: (760)597-1500 Fax: (760)597-1510 Datron World Communications, Inc. Vista, California -----Original Message----- From: Tom Stearns [mailto:[log in to unmask]] Sent: Wednesday, November 01, 2006 10:11 AM To: (Designers Council Forum); Brooks,Bill Subject: Re: [DC] Flex Circuit costs... sticker shock? Bill: Flex is a custom designed and custom produced product so it will always cost more than a catalog item. You pay for the high engineering content which is always needed when something new is in the works. Compared with PCB's, flex is far more compex because the substrate is less stable dimensionally which means you need much more elegant tooling and tool concepts. All this hits at the startup which means small orders can be really costly. Ever order a scustom automobile? duPont charges well over $150 per pound for typical flex dielectric compared with maybe $15 or so for PWB materials. ----begin to see the picture? When you buy a piece of flex you are buying both an interconnections device and a piece of assembly tooling. Not at all fair to compare wire cost with flex cost---remember that wire is cheap, but takes a great deal of ghand labor to convert into an interconnection. Flex sharply reduces the assembly labrto---wire sharply increases it. Rigid flex is the most complex and difficult flex product to built. It contains mixed dielectrics and requires a greatdeal of in-process tooling. Compared with PCB's, rigid-flex takes at least 3X the manufacturing steps. When you factor in ridiculous MIL spec testing (which is primarily based on the concept of a guaranteed loss of 20% of production) you begin to sense why rigid-flex is costly. But rigid-flex makes all sorts of high density, high-rel packages possible; without rigid flex we would not have any of our high-tech weapons systems, smart bombs, etc. If it's a matter of bringing the pilot back alive after a successful mission, would you carp about a few dollars? Can't understand your application----I don't see how you could replace a rigid-flex board with a piece of ribbon cable and a connector. I think you are in need of a good applications engineer. Tom Stearns 3 Brander Court Nashua NH 03063 603 889 2522 --------------------------------------------------------------------------------- DesignerCouncil 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 DesignerCouncil. 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