Identifying a Cox prop

I have a few in wood grain, and I think
they were also used on the Fokker D-7.
Fokker Triplane and Sopwith Camel.
All left hand start. These planes show
up on ebay regularly, so there may be
a small market for them. I have 5 new
ones, no packages.

Bob

As to the sellable question, I have couple of these that I've never tried. What kind of thrust do these produce?

The Untried Mark

I would buy a few.

batjac wrote:As to the sellable question, I have  couple of these that I've never tried.  What kind of thrust do these produce?
The Untried Mark

Good question. The design must have been mainly for asthetics, but
the prop still had to haul around a not very aerodynamic piece of plastic.
I've never seen a tractor/rh version of it.
It'd be interesting to put on an a stout reedy.
Bob

There is an attractive aspect for these particular props for 1/2A c/l "REED" speed, where the model is only flying straight and level. Most of us fly a CCW circle.. and having a right-hand prop tends to roll the model inward; requiring "leading" (whipping) when launching, to maintain line-tension and requires outboard wing-tip weight. Left-hand props on a reed-valve engine would roll the model outward and eliminate the need for outboard tip-weight.. thus making the model lighter too.. as well as easier to launch. The 4.5 x 4 size should be a good for .049 reed speed high-performance.. whether it's right or left hand.

We just wanted others to confirm that this is indeed a LH prop. That's what it looks like to us.

And yes, LH is preferred for CL flying due to torque steer pulling the aircraft towards the outer edge of a LH circle.

We bought them today and will be listing them as soon as they arrive at our office.

Good, I like those for Reed Speed testing. Only flying will tell, but that semi-scimitar shape, for lack of a better description, seems more efficient than the utilitarian props I tried to modify. I'll probably buy a couple to try.
Rusty