Karl, I see where your comittee is going now. Realy don't understand, but wish to, benefit to those like myself in the lowest of places where designers struggle while attempting just to effect DFM/CE for "normal" boards. I just finished readin on paper on CAF. It pointed to all you say with respect to X/Y axis issues. It also pointed to Z axis problems that may exist between, of course, two planes using a single ply of preg. I have reviewed, almost everyday JIPC/IPC 2315 and can envision issues here with CAF. However, in my wildest dreams, could I have cooked up the omnipotent schemes, indicated in that guideline, regarding so many variations as micro vias, buried vias, buried micro vias, very high aspect ration interfacial vias, and multiple combinations thereof. I'm really not carping about all this. I'm just wanting to get back to normal 20 or 50 layer boards that have been around for many years without regard to needing anything like CAF. Just one other thing: There is talk of issues with hollow glass fibers. I'm really missing something as these fibers are but 7-9 microns in diameter. How can they be hollow or, even if they were how could they possibly affect CAF? Oh heck, one other thing: I have admonished all those using resin poor glass styles for years. Haven't we gotten past this stage. Most of my "relatively" dense designs don't even allow 2116 glass styles. Is anyone really doing four layer boards that are in any way interested in CAF Just trying to broaden my horizons a bit while offering some considerable years of experience doing this stuff at the "street" level. I realize the difference, now, between cleanliness and CAF. However, the gap is much too narrow for me to feel comfortable with what you all are doing by separating the two. Highest regards, MoonMan --------------------------------------------------------------------------------- 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 ---------------------------------------------------------------------------------