No expert here, but I do have a few carbon fiber GP's with balsa cores that I made and use. My suggestion would be that you need some separation to make the blade more ridged. Foam, balsa, wood... thicker down the spine, as I see it the paddle has no backbone. Don't throw it away could make a good fly swatter.
Joe

: I thought I would post this here, even though I'm referencing a
: canoe paddle I built. There seems to be such a rich and varied
: set of experiences here on this board and my chances are good
: for answers to my question.

: I built a canoe bent-shaft paddle (an experiment because I liked
: the looks and feel of the Mitchel Leader paddle); wooden shaft
: (wrc & ash) with a walnut grip. The blade is carbon fiber -
: 4 layers of 3K twill. I used MAS epoxy - low viscosity and slow
: hardener to wet out the layers. I reinforced the blade area in
: the center with a 1/4" thick piece of cedar, about 2
: 1/2" wide.

: My problem is that outside of the reinforced area, the paddle is
: quite flexible. I'm not implying that the blade is rubbery - but
: griping the thin blade, one can flex the blade maybe 1/4".
: I was expecting a very rigid blade. Is carbon fiber by itself
: not that rigid (even with 4 layers)? I don't like the shape of
: the non-powerface blade. If additional reinforcement is needed,
: would a thin foam sheet work? I want to build another with a
: stiffer blade without have the thickness and weight of of wooden
: blade covered with carbon fiber. Any advice is appreciated.

: A video showing the blade as I spin around the paddle shows the
: blade shape:
: http://www.bluestempaddler.com/newcf-update/

: A more detailed description of the build is here:
: http://www.bluestempaddler.com/newbentshaft/