zfennell wrote:
...
they never mention the torsional stiffness of the uni-rods. (not so much, i bet)
the fibers that do that job will need a home, too
Bille, i bet you already know better, but are too busy selling the carbon.
i'm sold.
however, i still believe in "good, fast, cheap, ....."
Making Molds, filling them with composites IS what i consider
"good, fast, cheap, ....." ------------------carbon can be had for $25 a pound
and an aircraft grade of Epoxy goes for $100 .
I do Not sell carbon, i Do sell the idea that composites are a Good
alternative for making stuff though.
** You don't get the torsional strength from the rods, unless they are also
laid up on a + - 45deg.
In the Strut :
My 12K stitched carbon on a + - 45 will carry the torsional loads. The carbon rods
will carry the bending loads of the Strut on there 0/90deg arangement; they go on
the High-point of the airfoil
and run parallel to the length of the strut. Then i place in a core, (nomex honneycomb)
or balsa, and then another inner skin to carry the shear loads of the outer skin
which makes the Local stiffness of the skin Way higher than without it.
I WILL place a shear-webb to hold the rods in space ; Much better
than the hollow aluminum your talking about, and after i make (1) the
next one will take 1/2 the time. Most of the labor is in the actual Mold.
Haven't got a mold yet, and a picture is worth a Lot of explaining, so
i need a bit of time here please !! Just ONE glance at the lay-up, and
i'm Certain you will immediately see ...
A guy COULD get this same lay-up by bending balsa around a broom-stick !
No Mold , but you will need a bit of filler to finish the exterior before paint.
I'll be spraying My paint directly into my mold.
Bille