Another option that works quite well is using clear (unpigmented) 
     soldermask and covering the fiducials with the soldermask.


______________________________ Reply Separator _________________________________
Subject: RE: Exposed Copper on Assemblies
Author:  [log in to unmask] at corp
Date:    2/26/96 7:48 AM


Reflowing solder paste on fiducials and in-circuit test pads shouldn't cause 
any problems.  We've been performing ICT on assemblies with solder on the test 
pads for years.  I can't speak for all, but I know that the majority of 
component placement systems can read solder coated fiducials quite well.
     
Jim Marsico
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