1% crunch

JIMRPT@aol.com JIMRPT@aol.com
Sun, 08 Sep 1996 17:03:01 -0400


John H;
"Most SB cracks start out as compression set or compression failure (cell
damage)."
  John- since all of the  cracks I have seen in sounding boards have ran with
the grain and started out on the top of the board shouldn't there be an
explanation other than compression failure that started the crack?. It seems
to me that if 'compression' failure caused the crack that it would appear on
the bottom of the board first (I am talking theory, not real life). I would
assume that if 'compression failure caused the crack that the ribs glued to
the underside of the board would keep that portion from showing any cracking
until the top side had split away completely. After all if the top of the
board is the outside of the APROX 60' circle, and the bottom of the board is
at a point inside of the circle, isn't the bottom of the board at
 compression and the top at extension ?
  John most of the cracks I see (Southeast) are at glue lines and are between
two distinctly different grained panels, would compression failure play a
part here as well?
 Not being critical John, just curious.
Jim Bryant (FL)






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