Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.


PCB baking for moisture outlet....

#18523

PCB baking for moisture outlet.... | 31 December, 2001

Hello,

Are there any rules for PCB drying (baking) before assembly; Date code criteria, finish process on PCB, storage conditions.. ect. I know some assemblers that are baking all PCB (not ENTEK!) as default before assembly, is it realy nessesary? is it written anywhere (IPC...)??

Thanks Roni ORBOTECH

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#18528

PCB baking for moisture outlet.... | 31 December, 2001

Baking before assembly does nothing good. It: * Increases costs. * Adds steps to the process and makes scheduling more cumbersome. * Increases the amount corrosion on solderable surfaces.

We used to bake to remove the moisture from boards that caused 'volcanoing' in wave soldered connections. The need for baking was elimated by: * Increasing PTH plating thickness to 1 thou minimum. * Storing boards in a controlled environment. * Using boards within three months. * Packaging long store boards to reduce moisture absorption.

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