Hi Jerry & Dave & All - Another possibility: If the lead frame on the devices you're dealing with was PLATED and not reflowed promptly after, then that may be the answer to your problem rather than any alloy combination. Most of the tin/lead platings lose their solderability rapidly after application unless reflowed and cleaned immediately after plating. One additional test that you might try, in addition to an alternate flux, might be to try a "bright dip", then rinse, flux and solder the parts immediately. Most of the bright dips are a 1 to 3% HCl solution which will do a pretty quick job of deoxidizing the parts. As above, this surface loses its solderability rather quickly and isn't something you would want to do for production. I think most of us have seen some fairly significant variances in finish alloys over the years, even on parts supplied from the same manufacturer. Availability of improved fluxes has probably done more to ease concerns and difficulties encountered in the military/government sector of the industry than anything else in recent years. Regards - Kelly ################################################################ 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 ################################################################