Electronics Forum | Fri Aug 01 00:22:46 EDT 2008 | fowlerchang
Pattern design, paste volume,printing misalignment, place misalignment,reflow process include N2 usage. All the factor above can make tombstome happen. And the most important factor is placement misalignment except design issue. But pls check the sol
Electronics Forum | Tue Feb 11 09:47:53 EST 2014 | spoiltforchoice
Perhaps a photo of the faults you are encountering might shed some light on the issue. I would think it would take some extremely poor paste handling or paste for the paste itself to be the root cause of what you seem to be describing. I would be inc
Electronics Forum | Tue Feb 11 09:01:54 EST 2014 | emeto
You should get your paste in ice(dry ice). Then you should keep it in a fridge. Many pastes now have 1month shelf life(after you take it out of the fridge). If you follow all the above, you might be having: 1. Lot problem - try different lots of you
Electronics Forum | Mon Feb 10 16:59:57 EST 2014 | hegemon
It is sort of a self answering question if you come in from the solder paste angle. First....start gathering data. Check every day, or every new paste jar, for: Storage conditions (temp), paste expiration date, ambient temp and humidity where yo
Electronics Forum | Wed Aug 16 14:36:06 EDT 2017 | duchoang
Not enough solderpaste. Uneven solderpaste volume on pads. Bad quality of caps ( Metal ends), try new cap manufacturer, sound weird, huh!! but that happened to me. Good luck.
Electronics Forum | Mon Aug 14 14:27:00 EDT 2017 | emeto
Here is some food for thought. Try to answer these questions yourself and I am sure you will see huge improvement. Reasons: - Bad PCB design - Plating-uneven HASL cause more than OSP Au/Ni or Silver - Poor paste and print quality - uneven paste ca
Electronics Forum | Tue Sep 11 09:41:30 EDT 2001 | davef
The fine "quality folk" that are laying this reasonable requirement, but are unreasonable in their attitude and approach. They should be sitting down with you and explaining: * Why the requirement is reasonable and necessary. * What are the acceptab
Electronics Forum | Wed Oct 11 18:12:55 EDT 2023 | alexv
I don't think it's a stencil issue. You have an identical inductor next to t=it, that's perfectly straight. You have a problem in that location. I've seen some inductors be affected by slight magnetic forces in the reflow oven. Try to rotate the boar
Electronics Forum | Fri Jul 15 16:50:04 EDT 2005 | davef
Few of us here on SMTnet fabricate our bare boards. Most of us are assemblers. So, the solderability of the connections of our boards is a BIG issue with us. Our suppliers protect the solderability of the copper by coating the copper to limit the
Electronics Forum | Thu Jul 05 17:10:29 EDT 2007 | arun2382
Thanks all! I'm facing this issue with one specific batch of QFNs. It could be a plating issue. But, nothing was evident from visual inspection,No sign of voiding or non-wetting. Cross-section images of solder joints were clean as well. Could this s
