Electronics Forum | Fri Sep 08 10:23:38 EDT 2006 | slthomas
By profile (profile has not been changed) are you referring to the oven zone settings or the actual charted profile of a trip through the oven as recorded by a thermal profiler? Some ovens will continue to function without warning as long as temps
Electronics Forum | Fri Jul 07 09:15:23 EDT 2000 | K. Chak
Hi Dave, This particular p/n calls for print&etch for wet process..and the problem occured due to surface contamin. with resist residue resisting copper from etching off. The high pressure nozzle was a problem at developing oper. and it is fixed now
Electronics Forum | Tue Feb 09 16:53:06 EST 2021 | SMTA-64387083
The size of the pad changes among the two. A solder mask defined pad will always be larger than a copper defined by your mask expansion setting. This will affect paste volume, if your standard paste aperture is designed for copper defined pads you m
Electronics Forum | Thu Sep 07 10:45:46 EDT 2006 | vicknesh28
Yes solder is reflowing on the pad but doesnt wick up the lead. Solder paste is sufficient. It just forms a saddle like appearance beneath the failing lead. The failed lead doesnt get reflowed at all. What puzzles me is how can hundreds of leads wet
Electronics Forum | Mon Aug 27 10:58:44 EDT 2001 | Ryan Jennens
Steve- We had the same trouble with 0805 Panasonic film caps. We had some tombstoning and open solder joints (non-wetting). We found two problems...like you, we changed our pad design to meet their recommendation. Also, they were able to suppl
Electronics Forum | Fri May 26 04:58:19 EDT 2023 | auriga2001
I agree with the two other replies. Left alone, it is a defect. If it's just excess adhesive or coating, you can use IPC-7711/7721 'Rework, Modification and Repair of Electronic Assemblies' for guidance on removing. Section 2.3.1 explains how to te
Electronics Forum | Fri Apr 29 14:16:16 EDT 2011 | ppcbs
Below is the long explanation. This defect is most commonly found with BGA components, but can arrise with all components. I see it happening more now with lead free boards that are being assembled with a no clean flux. Best short term remedy is t
Electronics Forum | Fri Aug 04 06:43:40 EDT 2017 | kubabel
Dear all, I´d like to ask You, if somebody faced similar situation like we are facing in our plant right now. We have wetting problems with some of our products. During SEM/EDX we found on non-wetted parts residues of Mineral oil - white - heavy. Do
Electronics Forum | Wed Oct 27 19:50:59 EDT 1999 | chris
Hi What is the possible cause of non-wetting of solder paste to the gold land pad. What we observed in the surface of the non-wet pad is an organic FM, and using FTIR we found out that it is a flux. It is possible that the cause of non-wetting is
Electronics Forum | Thu Oct 28 09:25:35 EDT 1999 | Dave F
Chris: Typical non-wetting causes are: * Poorly controlled soldering process * Incorrect material * Surface contamination * Insufficient preheat * Misapplied solder mask * Shadowing Without intending to insult you, all of the causes of non-w
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