Ioan It may still be a board problem. I would bake some boards and assemble some suspect parts. By the way, what board surface finish are you using? Best regards Lee J. Lee Parker, Ph.D. JLP Consultants LLC 804 779 3389 ----- Original Message ----- From: "Tempea, Ioan" <[log in to unmask]> To: <[log in to unmask]> Sent: Wednesday, June 21, 2006 8:56 AM Subject: [TN] Blowholes pandemic Hi Technos, for a couple of days I see occurences of blowholes in the joints of, guess what, SMT 0603 resistors. The reflow recipe did not change and we're talking about 2 different established products, we have run many of each before. One is WS, the other one no-clean. Each one uses different brand of solder paste, SnPb. I have changed the paste with fresh one, no positive results. I have changed the reels with different date codes, Bingo! But even the "bad" parts were quite fresh, less than one year old. One of them is pure Sn plated, don't know about the other ones. The question is: where on Earth can humidity stay in a ceramic resistor? What else can be the cause of the blowholes? Did not bake the boards, since changing the components worked, so I guess the PCBs are out of the hook... Thanks, Ioan --------------------------------------------------- Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------