1. Are the boards you are testing from the same bareboard production lot that the problem boards are from? ""YES, These are boards the customer brought back to us for evaluation, they are from the same lot as the ones causing all the woes."" Are they from the clients storage or are they boards you have retained at your facility? ""We shipped them over a year ago to our customer, they have been in their storage wharehouse until a month ago."" 2. Was the client doing the assembly seeing this problem on other/different boards at the time? ""NO, just this particular lot."" 3. Is the problem specific to a certain area of the board or all over it? ""It appears random across the board."" 4. Is the problem specific to a certain type or style of component? ""All components are through hole leaded, .035" .040" hole dia."" 5. Is it possible to obtain and test a sample of the exact flux that was used to solder these problem boards ? ""I am requesting some"" >Answering these should help to better direct you to the cause. >I have seen similar outgassing problems from contaminated wavesolder flux. It would volatize in the solder >wave causing the same "swiss cheese" appearance, although not severe as this one. If you look closely at the >pictures, especially pic 2, the outgassing does not look like it is originating from the hole wall which >would be the case if it was strictly moisture absorption in the board coming out. Although it is difficult at >times to determine origin when looking at a two dimensional finite slice of a three dimensional object. ""We had performed the cross-sections in three-axis, on 90's from a few angles and top-down images observing the same results regardless, i.e. voids/bubbles within the solder not inter-acting with the hole wall (copper) at any point. Thanks for all your input Franklin ############################################################## TechNet Mail List 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://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################