In your message dated Wednesday 23, October 1996 you wrote :
> Every so often a board might require baking if the storage conditions were
> poor, or the vias were masked/tinted and did not cure properly.
> At any rate 125C is an accepted temperature, and 2 hours should be adequate
> to drive out moisture and/or help cure the masking.
>                                                          Steve A

I think 125C may be a little on the high side. 100 C tops is good enough for 
moisture related problems. A long low temperature bake is better, and 80C for 2 
hours is adequate if the problem is due to moisture. If the solder mask is not 
cured properly then the higher temperature will be needed but that is not to do 
with moisture.

I agree that this bake should not be necessary if pwb's are of good quality but 
some assemblers have it as part of their process for a belt and braces. We used 
to bake all incoming laminate but now our suppliers do it.
-- 
Paul Gould
Teknacron Circuits Ltd
EMail [log in to unmask]

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