I a previous company, we used to have internet switch blade supports made of metal which ran in metal card guides. This caused quite a lot of trouble when the material was pre-plated before stamping etc. the plating flaked off into the unit over time and blade insertions into the chassis. The process was changed to a post plate process and the problems went away. John John Burke (408) 515 4992 -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Dehoyos, Ramon Sent: Thursday, December 07, 2006 11:27 AM To: [log in to unmask] Subject: Re: [TN] Metal against metal in chassis Hi Ted: In a chassis there are shelves and the shelves are attached to the frame of the chassis. As long as the mating surfaces are tight using lock washers metal shavings should not be a problem. But metal under a BGA, will be catastrophic. Soft metal will shed metal easier, i.e. aluminum, than SS. regards, Ramon -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Ted Kong Sent: Wednesday, December 06, 2006 2:11 PM To: [log in to unmask] Subject: [TN] Metal against metal in chassis Hi all, Have anyone seem mechanical designs with metal agaist metal in chassis? I do know there will some metal shavings, but will it cause any failure if it get underneath the BGAs? What others problems might this cause. Any feedbacks and comments are welcome. Thanks all in advance. Ted ________________________________________________________________________ ____________ Yahoo! Music Unlimited Access over 1 million songs. http://music.yahoo.com/unlimited --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------