Wayne, How about turning the board over and shaking it? But that will only give you evidence that at least one pad is wetted. On a more serious note.. The types of defects that I have seen with these style parts are obvious - parts way up off the pads. I have not seen any purely non-wetting defects. But if you can't see enough to find evidence of wetting, perhaps a lack of evidence of non-wetting is enough? If the part is in the correct position and any observable solder (pads should extend out from under the part) appears normal - the shape is consistent with other locations - then is that evidence enough? Ben -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of Wayne Thayer Sent: Thursday, April 10, 2008 10:35 PM To: [log in to unmask] Subject: [TN] FN Parts--Evidence of Wetting Relevant IPC specs claim that no toe fillet is required for DFN/QFN parts and there is no minimum solder joint height. The only requirement for the joint other than alignment/pad size is "evidence of wetting". How do I get this evidence without a toe fillet? I suppose if I have enough joint height I can see under the part like a BGA, but I've never seen a FN part mounted that high. Would be nice if the spec included some pix/examples of this "evidence". Any recommendations would be very much appreciated. Thanks, Wayne Thayer --------------------------------------------------- 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 -----------------------------------------------------