Comments are: * It�s interesting, but not surprising that your time above liquidous varies around the sides of this component. * You are correct in thinking that it is better to reduce than to increase the temperature differences around the component. * It�s possible that N2 could help your solder wetting, but that would vary according to the source of this problem. * Originally on this thread, we were talking about poor soldering of the toe of a QFP, but the problem you have is different than that problem. The area of your wetting problem is larger than the toe of the component lead. Your problem could be cased by a range of things [ie, connector lead solderability, pad solderability, low activity flux, insufficient paste deposition, poor placement accuracy, etc] that could be in addition to setting the proper heating recipe for your oven that you�ve been talking about here.
Focusing on your question about your reflow recipe, rather than focusing on trying to minimize the differences in time over liquidous on various sides of this component, consider profiling and setting temperatures on that one side of the component that is giving you fits [the one where you see the poor wetting] and letting the temperatures on the other sides of the component pretty much fall where they fall.
Finally, if you think there could be issues affecting the wetting of your component that are broader than the recipe issues that we�ve been talking about, understanding more about the situation would help us make a contribution.
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