We don't know yet John. I would not attempt to nail Butch down on the
price just yet but I would guess way less than a Hoffman or MT.
For one thing it is up to you to build the carbon composite blades.

Paul

Ouch!  I see that as being way beyond my ability to do well enough that I
would want to fly behind it.  Are there any production prop blades which
would be suitable?

Dave Leonard

You could always hire a gupp type person to build the blades for you Dave :-)
Don't worry! We are developing a method that anyone can use to build
accurate blades. Here is an early concept. This is not the metal hub
which will be supplied. The hub has been improved and the threaded
portion eliminated.

Paul Lamar

What about Warp Drive carbon fiber blades?  That is what I'm using on a
Mustang II, with auto engine.

AI Nut
posted aft, per request

People have had some problems with those failing on the higher HP piston engines
like the O-360. Also the twist of the blade is less than optimum for
an airplane that flies at 200 MPH. They work fine at the lower speed ranges
as Ken Welter uses a five blade version on his rotary powered Coot amphibian.

The third problem we have with them is they are not wide enough for a two
blade version to absorb 200 HP. Our hub will be limited to two blade
props for quite some time as they are more efficient than multi blade 
versions. 

A fourth problem we have with them is the center of pressure does 
not coincide with the hub axis so the force or torquerequired to change 
pitch in the air would be higher than an optimized blade plan form design. 

Did I forget anything Bill? :-)

Oh perhaps Bill does not like the air foil used either. I know I am skeptical
about it.

Paul Lamar
 
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