Paul..

        You are correct in that the specs are for the finished pwb.
   The pad/hole relationship is determined using the specs, contractual
   obligation, INCLUDING manuf. tol. In fact, over many years/product
   lines, we have experienced very few problems with procduct from the
   fabricator. That is due to the fact that we have our fabricator(s)
   concur with our end product requirements as delineated on our pwb
   master drawing BEFORE we release it into the product definition.

         The original question was in respect to larger internal pads in
   their designs and why, since we have never seen or done that ourselves.
   I was just interested in the rational that went into making that design
   requirement for possible implementation into our product line if like
   requirements occur.

        After all is said and done, the message is: Whatever set of design
   parameters are generated, communicate with your fabricator NOW to reduce
   problems later.

                                         Regards,
Bob Vanech                                          Bob
Norden Systems