The standard remaining thickness that HADCO recommends is
          .012" (+/-.002") for .062" thick boards.  The +/-.002"
          tolerance implies that the vendor is using simultaneous
          rather than flip scoring.  With simultaneous scoring, two
          blades with spacers do the cutting from both top and bottom
          of the board at the same time.  A flip score (where one side
          is done and then flipped over and the other side is scored)
          cannot keep such tight tolerance because the actual board
          thickness comes into play for the remaining thickness.
          Since most .062" thick boards are spec'ed out at +/-.007",
          any boards from .055" - .069" thick are within spec, and
          flip scoring would cause as wide a variation on remaining
          thickness.  Such a wide variation can cause problems when
          depanelizing.
          We also use a 30 degree cutter, and advise our customers to
          keep any metal features (traces, pads, thieving, etc.) a
          minimum of .025" from the edge(s) of the board which are
          scored.  More and more of our customers have moved to
          scoring for the following reasons:
          o    Zero Clearance - oftentimes better panel utilization,
               consequently lower cost
          o    Solid Array - eliminates sagging and solder splashes
               during assembly
          o    Ease of Separation - snapping vs. shearing or cutting
          o    Smoother Edge - vs. hole and slot "nubbies"
          Perhaps someone from the assembly side could better answer
          how far away from score lines components should be kept.
          Regards,
          Tom Coyle
          Field Services Engineer
          HADCO Corporation
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