I ran down to our only hobby shop on the island for a C/F pushrod. wouldn't you know, they were all out.
I put one together using graphite and 1/16 balsa, 1/4" wide.
I laminated the balsa together with the graphite sandwiched between each peice. Then I wraped all 4 sides of the "stick" with more graphite.
Turned out nice and stiff, and quite light too. Just square and not round.
I staggered the points where the threaded rod join the square rod so I don't lose too much strength, and wrapped it with kevlar wicked with epoxy... Just as they did it back in the 80's. [8D]