I might suggest that if your board size is not the one specified by your terminal, counterbore the board until it is the right size. Terminals are designed to fit a specific size. It is up to the designer to supply a board of that size. Mike Green Production Design Engineering Lockheed Martin Space Systems Sunnyvale, CA 94089 -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of Brooks,Bill Sent: Tuesday, March 29, 2005 9:00 AM To: [log in to unmask] Subject: Re: [TN] Solder Terminals Hi Robert, Yes... I recall the acceptability of cracks in terminals and eyelets... Thanks for the reminder. It's been a long time since I have had to deal with them. Your last comment on PTH swaging of terminals... I thought they didn't allow that in the Mil Specs... there was an issue with damage to the PTH I think... We always added multiple vias around any non-plated or plated mechanical hole that was used for ground and/or mounting or if the board was under any mechanical compression so as to guarantee that the continuity of the pads on top to the planes and pads on the bottom was maintained by a via free of mechanical compression... regardless of any single failure in a mounting or swaged terminal hole. It was just 'good insurance'. Do you have the specific spec numbers for those? I'd like to look at them again. Best regards, Bill Brooks - KG6VVP PCB Design Engineer , C.I.D.+, C.I.I. Tel: (760)597-1500 Ext 3772 Fax: (760)597-1510 e-mail:[log in to unmask] http://www.dtwc.com http://pcbwizards.com -----Original Message----- From: Langston, Robert L [mailto:[log in to unmask]] Sent: Tuesday, March 29, 2005 3:08 AM To: [log in to unmask] Subject: Re: [TN] Solder Terminals Cracking of the solder terminals is a subject that has been around forever and is not confined to any one supplier. IPC,MIL, and NASA Spec's address this and allow end item terminal cracks of a maximum of 3, if they are located at least 90 degrees apart, and none enter into the barrel of the terminal. Final swaging in a PTH should allow rotating the terminal with finger pressure. Bob -----Original Message----- From: Brooks,Bill [mailto:[log in to unmask]] Sent: Monday, March 28, 2005 1:02 PM To: [log in to unmask] Subject: Re: [TN] Solder Terminals They may have changed materials in the alloy on you... Check with the manufacturer of the terminals to make sure the alloy has not changed. Or if that isn't it, then maybe the plating process is affecting the brittleness of the material? Dead soft copper is very malleable and brass is less malleable. Most of the terminals I have used in electronics are tin plated brass with the only exception being copper eyelets back in the 1970's. I assume that you have not changed the hole size in the board and the board thickness is the same... The speed with which the material is 'cold formed' may also come into play... If you are using automated tooling the stops on the swage tool will have something to do with preventing over stretching the material to the cracking point. The 'very old' terminals comment you made makes me suspect that the materials have changed rather than the process of forming them with the Cambion tool. Just a guess. Work with your supplier and see if the old batch of terminals came from a different source or used different materials. Best regards, Bill Brooks - KG6VVP PCB Design Engineer , C.I.D.+, C.I.I. Tel: (760)597-1500 Ext 3772 Fax: (760)597-1510 e-mail:[log in to unmask] http://www.dtwc.com http://pcbwizards.com ---------------- Hi Technetters: I would like to know if anybody has experienced difficulties in flaring the flange of solder terminals. On J-std-001C 6.2.3 it states that the angle of flare shall be between 35 and 120 deg. Some terminals crack even if they are flared at 36 deg. Other terminals can be flared at 120 deg and not crack. I suspect that the plating finish has a lot to do with it. Regards, Ramon --------------------------------------------------- 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 ----------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------