Sender: <marv@lancaironline.net> (Marvin Kaye)
To: lml
Date: Sat, 06 Jul 2002 09:59:49 -0400
Message-ID: <redirect-1610205@logan.com>
From: "Gary Casey" <glcasey@adelphia.net>
Subject: carbon fiber
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<<Having spent many hours doing layups in both carbon fiber and e-glass, I
have come to the conclusion that if I were to build another glass airplane,
I would throw the e-glass away, and do everything in carbon fiber (I'd use
glass where antennas need to work.)>>

Yes, but...In an all-carbon structure there is no question.  But if one were
to build a glass aircraft and then use carbon for all the assembly joints I
would be afraid that the elastic modulus miss-match could cause problems.
As I recall, carbon composites have a modulus something like twice that of
glass and therefore, the joint will not flex with the rest of the structure,
causing stress concentrations at the joint.  I know that on my ES there are
several glass-to-carbon joints and I can only assume that this stress
concentration was figured into the design.

Gary Casey
ES project, still chasing bubbles