Electronics Forum | Thu Sep 07 09:08:57 EDT 2006 | Bubba
OK, part touching paste before reflow? Check part. Maybe bad plating. Check reflow profile by slowing conveyor.
Electronics Forum | Fri Sep 08 08:00:41 EDT 2006 | davef
That's your clue. Your reflow is running ~240*C and your soldering iron is running ~370*C. Dial-up the heat.
Electronics Forum | Thu Sep 07 10:32:12 EDT 2006 | slthomas
Is the solder reflowing on the pad but not wicking up the lead, or does there appear to be insufficient solder to wet both, or is it not reflowing at all, or.....? Have you verified your profile? What is the condition of your paste (expiration date,
Electronics Forum | Thu Sep 07 07:41:06 EDT 2006 | Bubba
Check for coplaner leads if this just exists at reflow process, i.e. look at part before oven, turn on 3D at placement machine. If you see after wave solder, the wave could cause coplanarity issues on top as well if you are going slow enough to refl
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 | 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 | Wed Sep 10 12:56:26 EDT 2008 | vladig
No arguments there. I 100% agree that quality engineers can and do solve a lot of problems on the spot. I've nevern said "run an analysis as soon as you get a problem". The whole nine yard started with a solderability problem. In my previous product
Electronics Forum | Fri Sep 14 02:18:32 EDT 2001 | gsparka
Hi. After reflow soldering. There are lots of non wetting of leads. 71 b'd all are mounted resister,condensor,qfp,plcc,bga have got the defects so many. all defecs occured in the fine pitch ic. others are good. On some fine pitch pads not mou
Electronics Forum | Wed Mar 30 01:01:10 EST 2005 | vicknesh28
All, Has there been any finding from the component point of view in terms of non wets after reflow and if yes, can anyone share what was improved on the component to reduce the non wet defective levels. What would be the contribution from the compon
Electronics Forum | Thu Mar 31 06:09:19 EST 2005 | amstech
Yes, components do contribute to the non wets in fine pitch reflow. Oxidation is the main culprit. May ask where it is coming from. Can not say in particular. May be burn in test process or end of line baking, hot / cold testing and need to run DOE'
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