Electronics Forum | Tue Mar 10 22:27:14 EST 1998 | DWR
What does the term "poor wetting" mean as a defect code ?
Electronics Forum | Mon Nov 12 19:47:33 EST 2007 | sin4d
Hi, Thanks. Waitng for your reponse. BTW, if I were to perform a test as below will this give me some result to indicate if the component is defective. 1) Print solder paste on plain PCB without copper track. 2) Mount the QFP & reflow 3) If the sol
Electronics Forum | Wed Mar 11 10:58:58 EST 1998 | Earl Moon
| | What does the term "poor wetting" mean as a defect code ? "Poor" should mean unacceptable when surface (component or PCB solder termination areas) wetting does not provide acceptable solder joints. Unacceptable wetting of PCB solder termination
Electronics Forum | Sun Sep 22 23:23:39 EDT 2019 | sssamw
Yes, no wetting on the several leads, to verify is same location of the leads? Looks PCB/IC leads wetting issue, a process contaminated or raw material issue. A cross experiments to verify the potential cause is needed.
Electronics Forum | Fri Sep 20 17:43:03 EDT 2019 | deanm
Looks like poor wetting/solderability to me. I don’t see heel fillets on the leads where the solder balls up. The solder has to go somewhere. It won’t flow where it won’t wet. Try printing a bare board and run through reflow. If the solder balls up o
Electronics Forum | Mon May 05 18:48:23 EDT 2003 | Kris
Hi, It is expected that lead-free will have reduced tomstoning. As it has a higher surface tension and does not wet as well as the tinlead paste it exibit lower tombstoning. Addiotnaly commercialy available lead-free alloys may not be true eutectic
Electronics Forum | Tue Sep 14 14:22:11 EDT 2010 | grahamcooper22
If the HASL was poor quality and very thin you would find this defect....but you would expect to see it on more pads also. Also, you'd expect to see your solder from your solder paste either dewetted on the pad or reflowed onto the BGA sphere making
Electronics Forum | Wed Jul 31 08:23:49 EDT 2002 | mcm4me
221C). 2D vision can very effectively detect % pad coverage, I use it on my DEK and this customer has an MPM which I also believe to be capable. Here is another fact, when the customer uses Brand X solder paste the defects due to what they call pad
Electronics Forum | Fri Dec 02 08:52:05 EST 2005 | pavel_murtishev
Good evening, I�ve just solved very similar soldering issue. In my case the problem was with 0603 chips. Solder joint had same appearance. I suspected that solder do not melted and increased TAL and peak temperature. No result. Next thing I tried to
Electronics Forum | Tue Jul 30 17:51:18 EDT 2002 | davef
Comments are: * Peak at 245�C for 40 sec seems like a very long time. I�d expect the time at 245�C to be 10 to 15 sec. This long time at peak could dewett the pads. * Really, their 2D vision on the printer can verify solder presence? * A thin coat
