Electronics Forum | Tue Jul 08 10:41:14 EDT 2008 | aj
Hi all, I was carrying out some trials and the attached image is something that puzzled me . What would be the cause of this ? is it excess volume ? poor wetting? aj...
Electronics Forum | Thu Jul 10 22:34:34 EDT 2008 | davef
We wouldn't get our underware in a knot about poor wetting on a lead that is not connected to the board. IPC standards seen to say that the inspector should use common sense in interpreting standards requirements. Then again, it's not all that common
Electronics Forum | Mon Jul 28 10:58:34 EDT 2008 | davef
Search the fine SMTnet Achives for background discussion on dewetting, like: http://www.smtnet.com//forums/index.cfm?fuseaction=view_thread&CFApp=1&Thread_ID=12840Message54734
Electronics Forum | Fri Aug 08 09:49:17 EDT 2008 | scottp
We've seen the exact same problem. The solder joints had negative wetting angles and x-sections show that the PdAg termination dissolved into the solder. We no longer allow PdAg terminations.
Electronics Forum | Mon Aug 18 15:18:08 EDT 2008 | realchunks
Open the same size as the via's anular ring. Any slight off print will wet its way back into the via hole.
Electronics Forum | Wed Aug 27 15:48:05 EDT 2008 | grics
Again, our paste manufacturer specifies TAL to be 30-60 seconds. Out of curiousity, how would part placement cause de-wetting? I am fairly new to SMT so elaboration would be helpful... Thanks
Electronics Forum | Fri Aug 29 10:18:31 EDT 2008 | rrpowers
We saw this one time when we were trying to develop some lead-free product. It ended up being copper migration. Some of the pads had a brown discoloration and those that did would not wet very well. Your elemental analysis would have shown if ther
Electronics Forum | Fri Sep 12 16:56:13 EDT 2008 | ppcbs
We have a double sided board with Immersion Silver Plating. After reflow the Silver turns a yellowish color. It still wets good, and the yellow color will polish off with a pencil eraser. Has anyone seen this, or know the cause?
Electronics Forum | Fri Oct 17 22:36:35 EDT 2008 | arosario
Hi All, We just started build a new product and I am encountering many non-wet rejects in our new product. I need help on what should I look into to improve our Yield. Please see below back ground 1. We are using DEK Infinity as printer. 2. We are mo
Electronics Forum | Sun Oct 19 08:11:12 EDT 2008 | davef
While you're waiting for others to reply to your question on component analysis laboratories, search the fine SMTnet Archives to find posts like: http://www.smtnet.com/forums/Index.cfm?CFApp=1&Message_ID=35636