Fab Gurus, We are designing board with a 40 mil BGAs first time and the fab will be having 10 mil plated finished holes on it. I opened up an old existing drawing of different non-BGA board and now I have couple of questions after reading my fab drawing notes. (1) Fab note: All holes to be within .006" true position on the diameter with respect to original data. Question: What is true position and why .006"? How to decide this number? (2) Registration: Front to back to be within +/-.005". Can anyone explain what is registration and why .005"? Who can decide this #, is it fab house's processing capability? re, Ken Patel ______________________________________________________ Ken Patel Phone: (408) 490-6804 1708 McCarthy Blvd. Fax: (408) 490-6859 Milpitas, CA 95035 Beeper: (888) 769-1808 ################################################################ 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 ################################################################