HADCO uses Ciba-Geigy's Probimer 65M LPI soldermask.  Our
          guidelines call for a bare minimum of .007" of spacing
          between solderable features.  This includes a .003" web of
          soldermask on the artwork, with .002" of spacing on each
          side for registration tolerancing.  This, and other
          information is available in HADCO's DFM manual - "A PWB
          Designer's Guide to the Galaxy", version 2.0,  available
          upon request.  It is also available on HADCO's web page:
          http://www.hadco.com:8080
          Tom Coyle
          Field Services Engineer
          HADCO Corporation
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