Cedric, How were the "fibers" in the solder joint able to short the SMT pads? Did the "fiber" grow to be a short or just strung from one joint to the other? If I saw that on a PCA I would assume that there was insufficient flux on the PCA or the flux was "baked" on the PCA before it hit the wave.... Paul Paul Edwards Process/Quality Engineering Surface Art Engineering -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory Sent: Monday, January 17, 2011 12:56 PM To: [log in to unmask] Subject: Re: [TN] Board failure due to fibber like fragments of alloy after wave soldering Hi Cedric, What does your last solder analysis say? You do get your pot analyzed don't you? Steve **** From: TechNet [mailto:[log in to unmask]] On Behalf Of Cedric ORAIN Sent: Monday, January 17, 2011 2:57 PM To: [log in to unmask] Subject: [TN] Board failure due to fibber like fragments of alloy after wave soldering After wave soldering of boards with both SMD and PTH components, 18% of the boards failed during ICT. The failure is due to shorts between SMD pads. These shorts are caused by "fibber like" fragments entrapped in solder joints. We are looking for root cause of this level of waste. These fragments are very similar in aspect with dross that we found on the top of the wave "head" after the pump stop. You can see dross picture in the pictures posted here: http://ipc-technet.groupsite.com/gallery/17663 The alloy is Sn63Pb37 and the flux is an alcohol based no-clean flux. Soldering under air atmosphere. The design of the board is ok. Dross is removed daily. Did you ever encountered this kind of issue (I mean with such a rate of defect)? I'm wondering if the aspect of the dross shown in the picture is normal or is it due to a pollution (metallic pollution: high Cu rate?? / organic pollution : epoxy, fiber glass fragments ...). Thanks for your in advance for your help and support, Best regards, Cedric ORAIN ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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.aspx?Pageid=E-mail-Forums for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 ----------------------------------------------------- ============================================================================== This email and any attachments thereto may contain private, confidential, and privileged material for the sole use of the intended recipient. Any review, copying, or distribution of this email (or any attachments thereto) by others is strictly prohibited. If you are not the intended recipient, please contact [log in to unmask] immediately and permanently delete the original and any copies of this email and any attachments thereto. ============================================================================== ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________ --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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.aspx?Pageid=E-mail-Forums for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------