Hi, David, Press fit/wire wrap connectors in military avionics motherboards have been around since Adam was a boy, and are even in "state of the art" equipment like the Eurofighter (sorry, 'Typhoon') radar, which underwent very stringent qualification testing indeed without any failure in that department. The budget for that project didn't allow much in the way of legal expenses for motherboard failure claims. Peter David Douthit <[log in to unmask] To: [log in to unmask] ORG> cc: (bcc: DUNCAN Peter/Asst Prin Engr/ST Sent by: Aero/ST Group) TechNet Subject: Re: [TN] Connectors and hole <[log in to unmask] diameters ORG> 02/06/02 01:46 AM Please respond to "TechNet E-Mail Forum."; Please respond to David Douthit Phil, Isn't is common to have press fit bus connectors of backplane boards like the multi layer VME bus boards? YES! How can this be different? It's not! Won't there be the same thermal cycling issues? Yes! Plus vibration and laminant damage around the immeadiate area! Just don't use this for high reliability electronics unless you have a very good lawyer! David A. Douthit Manager LoCan LLC Phil Nutting wrote: This discussion brings up a question for me. Our discussion has been centered on the fact that the holes are too small in diameter for the pin being inserted in the hole. The discussion has suggested that due to thermal cycling there may be long term reliability problems with the hole plating and possible connections to internal layers. Isn't is common to have press fit bus connectors of backplane boards like the multi layer VME bus boards? How can this be different? Won't there be the same thermal cycling issues? Just a thought. Phil Nutting --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d 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 delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 --------------------------------------------------------------------------------- [This e-mail is confidential and may also be privileged. If you are not the intended recipient, please delete it and notify us immediately; you should not copy or use it for any purpose, nor disclose its contents to any other person. Thank you.] --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d 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 delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------