Vishy, GSC makes several variety of fixtures to hold flex circuits flush and flat during the smt and other assembly processes. We can utilize a number of hold down techniques depending on what will type of flex circuit you are working with. Give me a call and I'll see if we can help you. Jim Gleason GSC 972-494-1911 www.gogsc.com -----Original Message----- From: Narayana Vishy-CVN002 <[log in to unmask]> To: [log in to unmask] <[log in to unmask]> Date: Friday, March 12, 1999 1:18 AM Subject: [TN] Flex circuit flatness - Is the solution out there ? >Hi Technet pals : > >Flexible circuits have this natural tendency to be flexible . They tend to >springup , bend ,kink & warp due to natural flexibility & handling . > >This behaviour is a major headache for the manufacturing engineers during >the assembly process of these circuits - Defects & more defects ! >The non-flat nature of these circuits is the root cause of numerous defects >like misaligned , unflush and unsoldered components . Processes such as >solder paste printing,component placement & reflow oven are not very >resistant to such flexible , warped & bent surfaces . Keeping these ciruits >perfectly flat (like a PCB ) during these processes is key to eliminating >many of the defects mentioned. > >Not to mention that much of conventional automation strategies are not >easily applicable on flex ciruit assembly manufacturing - For example, >automated vision isnpection is an entirely different ball game when it comes >to flexible circuits. > >Now the questions : > >1) Is there anybody out there who knows techniques of holding the flexible >circuits down real flat ? >2) Are there technologies/vendors in the market who have adhesives >(sheets/sprays/liquids) which can : > a. hold down flexible circuit panels flat on a solid pallet >(carrier) > b. withstand the reflow oven temperature (max 290 deg >centigrade) > c. be peelable/detachable from the flexible circuit panel w/o >causing cosmetic defects on the flex circuit after the reflow process . > >Any clues ? > > >Thanks in advance, >Vishy. > >################################################################ >TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. >For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 >################################################################ > ################################################################ TechNet E-Mail Forum 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################