After subjecting samples to 1000 cycles of +85, -40 deg C with 30 min dwells I am inspecting the solder for cracks holes or voids. I notice that there are some cracks on the edges of SMT components (resistors and caps, no damage on the IC connections), IPC-SM-785 states that the crack must propagate through the entire solder connection to be considered a failure, also on my THP connector the solder appears "crinkly" - Friday afternoon tech talk! This is a mixed board, SMT reflow then THP wave using a pcb pallet to protect the SMT parts. I am wondering what would be the first step to determine what part of the soldering process should be reviewed. My first thought is that the larger SMT pads are picking up too much heat during the wave process and the solder is getting brittle. The reason I think this is that the IC leads have perfect - still shiny - solder connections. Thanks for any thoughts, Jason --------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8e 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 or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/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 -----------------------------------------------------