At 09:03 AM 12/31/96 PST, you wrote:
>     I would like to know the causes of solder blow-out in soldered PTH 
>     assemblies other than the insufficient copper thickness of PTH. 
>     We are encountered this kind of soldering problem on PCB with 
>     0.8mil(average) in PTH copper thickness.
>     Any help to identify the problem would be highly appreciated
>     
>     Best Regards,
>     
>     KP Chan
>     Email: [log in to unmask]
>
>********************************************************************

Hi Chan,

I ever encounter this issue before. Even the drilling and plating are good,
I still
faced this problem. 
I understand the raw material used for PCB fabrication is one of the
culprits. 

Try cleaning and later bake the board at 100 deg. C for 4 hrs.

Good Luck..

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