This sounds like a good solution.  One question though.  Can these vias 
also be used as testpoints or does the soldermask come down the hole and 
interfere with the probe making contact?
Thanks,


--- Chris Stack
--- Ext. 231                       
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--- CD Electronics, Inc.                   
--- Printed Circuit Board Designer and Purchasing Agent 

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When vacuum fixture testing is required we encourage our customers to use 

the following fix.

Soldermask phototools are created that leave an open pad area on the 
solder side but tent the component side of the pcb.  Our curtain coat LPI 

process of course does not tent or plug the vias.  However the subsequent 

wave solder process will!

This has the advantage that we have no risk of chemical residues from 
HASL being trapped in the via holes.  We can also mass produce plugged 
vias effectively without the use of dry film solder mask etc.

Our customers really like this cost effective fix and have not seen 
problems with solder balls on the top side.


Richard Wood-Roe
Artetch Circuits Ltd.
Littlehampton - UK