Dear Sir/Madam, I wonder if you can help, please forgive me for emailing you directly I was unsure as to whether the Technet forum was open to the 'general public' for posting .. I stumbled across an article that a Mr Bill Fabry had posted to the Technet forum regarding gold and embrittlement. I am working on the design of a single board computer and have designed in a surface mount connector which I am now told by the manufacturer (Samtec) that they can only supply with a gold finish. Our main customer for this board is a defense contractor and our own in-house rules (derived I assume from military standards) is that all connectors with a gold lead finish must be solder dipped prior to assembly onto the board. Our board is FR4 with tin/lead finish on the pads. So far two sub contractors have failed to solder dip these connectors, and even if they did succeed there would likely be a co-planarity problem. here is an extract of Bill's original posting to the Technet Forum .. >>SNIP From: "Bill Fabry" <[log in to unmask]> Subject: Re: Re[2]- Electroless Ni/Im To: [log in to unmask], "Thad McMillan" <[log in to unmask]> Reply to: RE>Re[2]: Electroless Ni/Immersion A Thad: Based on a reliability report generated by HP: If the gold content is less than 2% of the resultant solder joint volume, no appreciable solder embrittlement will occur. Therefore, the VOLUME of gold on ANY pad must be less than 2% of the resultant solder joint VOLUME, or ~1% of the VOLUME of solder paste applied to that pad. (e.g. if 0.005" solder paste is applied, gold thickness should be < 50 micro-inches.) >>SNIP Could you please advise, or refer me to someone who is able to advise on the following .. Q/. could I apply your guidelines to my connector or is it specifically only applicable to a gold finish on the board ? Q/. Could you give me a contact where I could acquire this HP reliability report ? many thanks, in anticipation, Kevin Minney ----------------------------------------CUSTOMER FIRST, QUALITY ALWAYS KEVIN MINNEY DY 4 Systems Inc **** *** senior designer 333 Palladium Dr M/S 317 *** * *** *** *** Kanata, ON ** ** ** *** *** * Tel: 613-599-9199 x208 Canada * *** * *** *** ** Fax: 613-599-7777 K2V 1A6 **** *** *** Email: [log in to unmask] *** ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC web site (http://jefry.ipc.org/forum.htm) for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################