Sounds like oxidation of the plating on the boards making for a really 
     bad solderability issue.  We have sent boards out to a board house for 
     replating with this same condition.  The cost is small and it sounds 
     like the problem your having is from the age of the boards and 
     solderability.  basically the replacer strips the solder from the 
     boards and replates with fresh solder and you will find the problems 
     should go away.  


______________________________ Reply Separator _________________________________
Subject: Assy: Blowhole
Author:  [log in to unmask] at _internetcc
Date:    3/5/97 4:07 AM


I have a serious problem on some of the board that stucked in the store. 
All of them is at least 2 years.
When I  wave-soldered the bare board, it has a lot of blow-holes, solder 
balls, pin-holes.
     
Anyway, I try to purge all of them, but there are 6000 pieces in the Store.
     
I try to bake at at 100 deg. C for 4 hours. Too bad, it doesn't work.
     
I try to bake for any 4 hours just before wave-soldering. The result is 
terrible. Not even a slight Help !!!
     
Can anybody give me some advises what should I do ???
     
Thanks in Advance
     
Poh ..
     
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