Before a recommendation can be considered would you provide information as to whether you are using a coplanarity device check, what type of machine is presenting the component, what thickness stencil you are using and what are your profile settings on soak temp and time and time above liquidus. Thanks, Jim Keeton -----Original Message----- From: Todd Ness [SMTP:[log in to unmask]] Sent: Monday, December 14, 1998 10:42 AM To: [log in to unmask] Subject: [TN] Fine-Pitch Soldering Problem Technetters, We are currently having soldering problems with a QFP 100 package part. The part is a TI microprocessor component with a 0.0196" pitch. The problem we are having with this part is we are getting intermittent opens with corner leads. Other fine-pitch components on this board solder fine. We have been building these boards for about 1 1/2 years in production with no problems until the last three months. I found out that TI recently switched the lead plating for this part from Tin/Lead to Nickel/Palladium. The solder paste we were using was Kester OA 596. However, due to the inability of this paste to solder to palladium parts, we switched to Kester OA 598. The profile was also tweeked per Kester's recommendations for soldering to palladium leads. All leads for this component and all other components on the board are soldering fine with the new paste and new profile, except for some intermittent opens on corner leads of the TI part with Nickel/Palladium leads. Component leads for this part were inspected prior to pick and place for coplanarity. Does anyone have any ideas of what may be happening and any recommendations for eliminating this problem. Happy Holidays ################################################################ 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################ ################################################################ 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################