Electronics Forum | Mon Nov 25 09:34:52 EST 2002 | davef
You're correct excessive temperature can cause dewetting, but that usually means realeeee hot. Excessive time at above liquidous will cause dewetting also.
Electronics Forum | Tue Dec 10 22:18:32 EST 2002 | davef
Randy's correct. If you were soldering to nickel with WS609, you would be complaining about non-wetting, not lumpy solder flow.
Electronics Forum | Wed Feb 26 15:27:21 EST 2003 | robert valles
Sounds like someone before you was dealing with tombstoning components. We have had greater success with triangular paeratures for 0603 and 0402 footprints. Granted the pad will not be wetted completly but IPC requirements are maintained.
Electronics Forum | Fri Mar 07 15:07:50 EST 2003 | davef
YiEng, MA/NY DDave: Usually when the gold plating bath goes south, you loose solderability.
Electronics Forum | Sun Mar 09 19:55:56 EST 2003 | iman
Which specific title books from under your pen, would you recommend for the avid process reader/learner? specific - talking about info/process/data wealth books, and not which books give the most royalties *grinz*
Electronics Forum | Tue Mar 11 12:20:13 EST 2003 | Jim
Look at "Dave's Book Shelf" here: http://www.smtinfocus.com/bookshelf/bookshelf.html
Electronics Forum | Tue Apr 01 11:50:08 EST 2003 | rdr
Dave, thanks for the info. This sounds like it would verify the presence of an open. We have verified that these balls are open and I am trying to figure out if we are fracturing or not wetting. causing these opens. I would use the die method on ne
Electronics Forum | Tue Jul 08 20:47:38 EDT 2003 | davef
Sam: If your gold overcoat was pourous, the nickel undercoat would corrode prior to your attempting to solder and you would not be able to solder without an aggressive flux. Since you see solder flow and wetting, it indicates the gold did an adequat
Electronics Forum | Fri Jul 25 04:55:37 EDT 2003 | iman
does the "non wetting" occur on the component terminals or PCB pad area? It sort of helps to get a better understanding of the symptoms.
Electronics Forum | Tue Sep 30 20:05:34 EDT 2003 | afm
Does alloy 42 lead frame on a QFP100 make lack of coplanarity (let's say 2 mils), a critical factor to have non-wetted leads? Lead coating is tin lead 90/10. afm
