Ryan
Sounds as if the toes of your QFPs are not plated but bare copper. Since
solder does not wet copper oxide it is clear that you cant see the solder
wicking over the toe and the bulging you mention is the effect of a
negative wetting angle. Again a sign that there was no wetting locally. I
wouldn't bother too much since on the heel you seem to have good wetting.
It has been shown in various tests ( please don't ask me for a reference
it's one of the things you read and think" OK again" and dump it ) that the
not wetted toes have no influence at all on the reliability of the solder
joint.
Best regards
Guenter
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