I agree Glenn.  Over the years I have seen drilling process data that
suggests the laminate drills differently with the seasons.  However, the
cure never seems to be off.  I wonder how humidity might affect the
behavior of the laminated panel.
More recently I have heard that laminate suppliers will be changing to a
sovlentless process.  How might this affect the material behavior?  Does
anyone have any information on this?
Drilbert
[log in to unmask] wrote:
>
> Richard,
>         Could it be the change of seasons?  I believe  humidity and
> temperature have an affect on several processes from the weaving operation, to
> impregnation at the laminator, to stack-up, and press.  But, I don't have any
> hard data to prove it.  Maybe the gremlin is Mother Nature in disguise.
>
> Glenn Pelkey
> Quality/Reliability Engineer
>
> Richard MacCutcheon <[log in to unmask]> Wrote:
> |
> | We seem to have developed a gremlin in our registration
> | dept.
> | A very large portion of scrap is attributed to NO Annular
> | Ring (<.002").
> |
> | Over 90% of our product is 8-layer GIL with 2 and 7 as
> | ground planes.
> | Cores are .005 constructed of 1-106 and 1-2313.  Prepreg
> | is 2313.
> |
> | Layer to layer misregistration is around .005" on average.
> |  Artwork pad
> | sizes are .022" over the max acceptable hole size.
> | Tooling seems to be as
> | tight as ever but in the last few weeks we have had an
> | inordinate amount of
> | scrap due to NO Annular Ring.
> |
> | What is the best systematic approach to take in
> | identifying the problem(s)?
> |
> | Thanks for your time.
> |
> | Richard MacCutcheon
> |