Do you do a moisture bake prior to using the PCB's? Do you have any turbulence to the wave? I have seen this defect mainly caused due to PCB moisture that is erupting causing the solder ball but also by a wave that had too much turbulence and the wave forces the solder to the top side.
My $.02 anyway.
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<DIV>Do you do a moisture bake prior to using the PCB's? Do you have any
turbulence to the wave? I have seen this defect mainly caused due to PCB
moisture that is erupting causing the solder ball but also by a wave that had
too much turbulence and the wave forces the solder to the top side. </DIV>
<DIV> </DIV>
<DIV>My $.02 anyway.</DIV></BODY></HTML>