Hole to Hole location tolerances for features drilled in the same setup (ie. Primary drilling) should be held to +/-.003". We see many designs that require +/-.002". This will apply to component holes where via locations become more variable as size is reduced. Location tolerances from setup to setup (ie. Primary to secondary drill will see the accumulative tolerance - from a minimum of +/-.004" is managed well - tooling, stack height, equipment, etc. Jeffrey Bush Director, Quality Assurance and Technical Support VERMONT CIRCUITS INCORPORATED 76 Technology Drive - POB 1890 Brattleboro, Vermont 05302 Voice: 802.257.4571.21 Fax: 802.257.0011 http://www.vtcircuits.com -----Original Message----- From: Scott Lefebvre [mailto:[log in to unmask]] Sent: Wednesday, May 04, 2005 6:10 PM To: [log in to unmask] Subject: [TN] Through hole drill accuracy I have looked profusely at IPC-6012 for a specification I could not find. I need to know if there is a specification for PTH drill accuracy and repeatability. We have a press-fit connector we are having problems with. The component manufacturer tested one of our boards and said the alignment is off 2 mils or more in some locations. I could not find what is the spec in IPC to reference to, could someone please point me to the correct document I should look at. Sincerely, SCOTT L --------------------------------------------------- Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------