Hi John, Our board cleaner is a roller-type machine (Teknek). In theory, the roller picks up any stray contaminants on the PCB (fiberglass, etc.) and deposits them to a sticky paper roll. We're going to look into our reflow ovens this weekend and see if we can find anything. The stencil cleaning process has already been investigated and found to be OK. I don't know what else to do at the moment. Leland -----Original Message----- From: John Burke [mailto:[log in to unmask]] Sent: Friday, May 16, 2008 12:36 PM To: Leland Woodall; 'TechNet E-Mail Forum' Subject: RE: Stainless Steel Contamination Question - Update Board cleaning machine?? Have you tried running something through the board cleaner which would trap particles if they are present?? Maybe run something like a pan scrubber (plastic) though the board cleaner and see if it traps residues. It really does sound like the contamination may be being introduced by some of the equipment that was cleaned using steel wool at some time?? Cleaning out the board cleaner? As for the reflow system. Take a panel of anything, spray it with photographic contact adhesive and run it through the reflow with all fans running with zero heat and see what sticks. You forgot the screen printer. The contamination may be present on your stencils/ screens - being introduced by contamination from the stencil cleaner?? John John Burke (408) 515 4992 -----Original Message----- From: Leland Woodall [mailto:[log in to unmask]] Sent: Friday, May 16, 2008 9:06 AM To: TechNet E-Mail Forum; John Burke Subject: Stainless Steel Contamination Question - Update Importance: High Everyone, Thanks for your previous help and suggestions, and hope you're having a great Friday. To update the group, there was another piece of this aggravating material found last evening on third shift. It is consistent in size, shape, and compositional analysis as the previous samples. It was found prior to the conformal coating process, so I was able to check the magnetic properties. It has none. Unlike the others, this one was found on the bottom side of the board. Removal of the material resulted in cracked flux and a slight visual indication of an imprint of the wire on top of one of the effected solder joints. If I'm now thinking correctly (may not be, as this is wearing me down fast), this was introduced to our product somewhere between our board cleaning machine and the exit of our first reflow oven. I intend to perform a solderability test this afternoon, laying a portion of the sample in two adjacent paste deposits and checking the results after reflow. I expect to see the sample still there, only having floated to the top of the reflowed joints but still encased in flux. Am I missing anything, or do you have any other suggestions on what I can do with this material in an attempt to identify the source? Thanks again for all your feedback in advance. Leland --------------------------------------------------- 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.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------