Why is it that you need tolerances that tight? In inches they are requesting .007" which is high. they shouldn't have to go higher then .005" (.127mm) I think they are adding registration with drill tolerance. Get them to break down their tolerances or what issues make them require this tolerance. I can see if they have a .004" drill tolerance and a .003" registration. Don't force them to do tighter tolerances then they request. That is what they are comfortable with. I am sure there are places that can do your request, but at what cost. Shop around a little more. Chris Robertson Design Engineer Lockheed-Martin Technology Services 4912 Research Dr. Huntsville, AL 35805 (256) 722-2626 [log in to unmask] Hiya folks! We are having some difficulty getting a flex supplier to build a circuit to our specs. The issue has to do with coverlay tolerance. They are requesting we open the coverlay openings so that they can use +/-0.50mm location tolerance. This allows for exposed copper between pads/lands to be soldered during installation. We have asked for +/-0.20mm tolerance, but might live with +/-0.25mm to +/-0.30mm. They **keep** coming back asking for the loose tolerance each time we say no. We have already taken into consideration the annular ring and adhesive squeeze-out, and cannot enlarge the openings by more than .10 or .15mm. These are typically 2 to 4 layer flex circuits with plated holes, polyimide lam with thermoset acrylic adhesive. Am I just being to picky? hardnosed? stiff-necked? all the above? What tolerances can I expect or ask for? Any alternatives or other details I may not be aware of? (Don't assume I know a lot about flex.. thanks.) Looking forward to your assistance, Sincerely, Roger M. Stoops, CID Trimble Navigation Ltd., Dayton, OH, USA Ph: +01 937.245.5288 Fax: +01 937.233.7511 --------------------------------------------------- Technet Mail List provided as a free 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 --------------------------------------------------- Technet Mail List provided as a free 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ----------------------------------------------------- -----------------------------------------------------