Carrie; First I have a question, is this a hard mount component? If this is the case it may be that an air pocket is forming below the component body between the solder and the component.. This type of problem could be covered in J-STD-001C 6.1.4. What could be done about it, maybe a spacer or a different prep on the leads such as what we call a cowboy crimp where the lead is crimped to prevent the component from going all the way into the through hole. That's what comes to mind as I read your problem. Hope this or another answer from some more experienced Technetters help. Thanks P. Lance Mayes Mfg. Trainer "Morse, Carrie" <[log in to unmask]> Sent by: TechNet <[log in to unmask]> 03/31/04 12:11 PM Please respond to "TechNet E-Mail Forum."; Please respond to "Morse, Carrie" To: [log in to unmask] cc: Subject: [TN] Voids in Thru-Hole Solder Joints We recently had circuit card assembly sent out for cross sectioning. One of the leads for a thru-hole device has voids -- perfectly round voids. The component body prevents us from seeing the top of the solder joint (which, if we could have seen, we would have seen a void). The bottomside of the joint has a void, but, would not have been visible without cross sectioning. The board was sent out for cross sectioning to evaluate a different problem, but, cross sectioning was done on a sample basis to evaluate the entire board. In other words, this specific component has not been a problem (yet). My questions are as follows: 1. What causes the voids over the wave? My first guess is insufficient preheat or dwell time. My second guess is materials (moisture in the board). Are these valid root causes? What else should I consider? 2. Are the voids detrimental to the reliability of the board? We use OA flux. I bet there is flux entrapped. That can't be good. 3. What is the acceptance criteria for voids in Thru-Hole parts? IPC-A-610 sec 6 covers circumferential wetting as well as percent fill as these are visible without cross sectioning. Is there a spec that covers what a thru-hole solder joint should look like cross sectioned? TIA, Carrie --------------------------------------------------- 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 847-509-9700 ext.5315 ----------------------------------------------------- --------------------------------------------------- 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 847-509-9700 ext.5315 -----------------------------------------------------