Phil, Dumb question, but can you put the resistor on the bottom of the board, and live with it? Kerry McMullen Principal New Product Mfg. Engineer LTX Corporation 825 University Avenue Norwood, MA 02062-2643 (T) 781-467-5468 (C) 508-631-1832 (F) 781-461-0993 Phil Nutting <[log in to unmask]> Sent by: TechNet <[log in to unmask]> 08/17/2007 08:14 AM Please respond to TechNet E-Mail Forum <[log in to unmask]>; Please respond to Phil Nutting <[log in to unmask]> To [log in to unmask] cc Subject Re: [TN] Solder mask as an insulator - illustration posted Good Morning folks, I created a graphic to illustrate our "punch through" problem as I don't have any photographs of the failed board/part. Steve Gregory has posted the illustration at http://stevezeva.homestead.com/files/LPI_punch_thru.jpg. Thanks Steve. Phil -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Stadem, Richard D. Sent: Wednesday, August 15, 2007 11:12 AM To: [log in to unmask] Subject: Re: [TN] Solder mask as an insulator Maybe. How many components, and what type? Can you post a picture on Steve Gregory's wall? It is a lot easier to solve the puzzle if we can see what the situation is. -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Phil Nutting Sent: Wednesday, August 15, 2007 9:59 AM To: [log in to unmask] Subject: [TN] Solder mask as an insulator Let me start with, I know that we should not rely on the LPI solder mask as an insulator. So I need recommendations for a simple and cost effective solution. Problem parameters; 0.062 thick FR-4 with 2 oz copper and LPI mask. PTH components laying on traces that go under the parts. PTH parts are shorting to the traces. Our fab house is against adding a second layer of LPI mask. On face value a second layer sounds good and easy, but I know there are issues too long to list. Short of raising the components above the board, applying an insulator under the components or a new board layout is there a better way of preventing this shorting problem? Thanks in advance. Phil Nutting Design for Manufacturing Engineer Kaiser Systems, Inc. 126 Sohier Road Beverly, MA 01915 voice: 978-922-9300 x1310 fax: 978-922-8374 e-mail: [log in to unmask] www.kaisersystems.com --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 15.0 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 15.0 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 15.0 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 -----------------------------------------------------