> I have an ongoing arguement with someone.  If there is .0018" of annular
> ring, are you allowed to "round-up" to .002"?  This is based on the fact
> that the measuring device resolves to four decimal places but the spec. only
> gives three.
>
> I think a minimum is just that, nothing below is acceptable.  Your
> thoughts..........

    This would need a few qualifiers. At the foot or at the pad top
(crest)? Allowing how much for edge imperfections, nicks and the
like on top of aconcentricity? Using a device that resolves to 4
digits, but does the operator add tolerance by how she or he sees and
sights things or a purely optical/mechanical device with no human
touch? How sure are we of its' calibration, optics, lighting or are
we to assume this is a "tree falling in an empty forest" type
academic question? Are you trying to foster a partnership with the
supplier or looking for an excuse to toss them off your AVL because
of a bad prior history? Are you the supplier trying not to get
excised? One hole of one board of 1,000 boards or 20% of everything?

   My point: All criteria, even cut and dried ones are subjective not
in their specified limits (you are right that it is a violation if
you gave all the right answers above) but in the application and
enforcement. These criterion are there to accomplish a goal. What
is your goal and does rejecting it further that goal or lessen the
likely achievement of it? Not everyone gets a ticket for doing 59 in
a 55MPH zone. Why? Because the officer is looking past the letter and
at the intent of the law. But, if enforced to the letter...the city
gets rich until the populace rebels and lynches the administration.
The military for some time made the paperwork criteria so burdensome
that they nearly had no decent vendors left that would deal with it.
Instead of improving the cut of performance, they found themselves
eliminating the upper-tier suppliers and having to deal with
sedimental bottom dwellers. Do you think this improved their net
supplied product?
    So, here were a few thoughts on the subject.

~Brian Nelson
  Sanmina Corp.

P.S. Should we answer the question despite the fact that 'argument'
is misspelled or stand on principle and reject the request for
thoughts until submitted with corrected spelling? - I'm kidding, but
it makes a nice analogy.

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