David, We haven't seen any of this interfering with or preventing a solder joint from forming. In every instance, it's clinging to the leads. Wouldn't that pretty much rule out our reflow ovens? The earliest part of our process where this has been found is at in-circuit test after the wave solder operation. That leaves our Omron AOIs, our Huntron visioning stations, and our flying probe machines. We've looked in and all around those processes, and still are coming up with nothing. Like trying to find a (stainless steel) needle in a haystack... Leland -----Original Message----- From: David Greig [mailto:[log in to unmask]] Sent: Tuesday, May 13, 2008 10:57 AM To: Leland Woodall Subject: RE: [TN] Stainless Steel Contamination Question Are the fibres causing any problems with solder joint formation, if so then trace backwards from the oven. If not then look around the oven and forwards to the point at which they are observed. What about the air/nitrogen source into the oven? Any bit of kit that is opened and closed regularly. The gaskets are used likely on electronic or even electrics enclosures, particularly clam shell cases. The cut ends of the gaskets typically do fray out loose fibres. Best Regards David Greig -----Original Message----- From: Leland Woodall [mailto:[log in to unmask]] Sent: 13 May 2008 15:29 To: David Greig Subject: RE: [TN] Stainless Steel Contamination Question David, Where in my manufacturing process might I find one of the knitted EMC gaskets? Are you familiar with any particular machinery that would use these? Thanks again, Leland -----Original Message----- From: David Greig [mailto:[log in to unmask]] Sent: Tuesday, May 13, 2008 10:26 AM To: 'TechNet E-Mail Forum'; Leland Woodall Subject: RE: [TN] Stainless Steel Contamination Question Perhaps an EMC gasket. One of the knitted mesh materials commonly used consists of knitted stainless steel fabric. There may well be residues of silicones and other lubricates used in the knitting or weaving. Best Regards David Greig -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Leland Woodall Sent: 13 May 2008 14:47 To: [log in to unmask] Subject: [TN] Stainless Steel Contamination Question Importance: High Hi Everyone, We've had a problem lately with fine strands of stainless steel wire being found on top of some of our .5 mm pitch ICs. This has caused both internal and external issues, and we've yet to identify the source. It's definitely formed wire, with a thickness ranging from 7 to 10 microns, and up to 3 mm in length. Our automated optical inspection stations can only reliably detect widths of 12 to 15 microns. I've checked the internet in an attempt to find common applications of this wire. I've found two, and they were for ultra-fine filters and stencil screen mesh. We've investigated (I think) all of our machinery that would utilize filters this small and have found no such usage. I've also checked every stencil in our plant, and all of our mesh material is some type of a plastic compound. Do you have any idea where this stainless steel might be coming from? Any suggestions would be sincerely appreciated! Thanks, 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------