Guaranteed to be 10 pounds lighter and stronger
 than Tracy's box. Interchangeable with Ross and Tracy gear boxes.
 Fits the new rubber coupling and Jeff's adapter plate with
 the built in main motor mounts. Prop rotates in
 the right direction.


 Paul Lamar

Looks like aluminum tubing with a reinforced ring at the base.

1. Are you planning aluminum piping for the shaft?
2. alignment during welding and cooling may be an issue. Will likely need
to build it and line bore it afterwards to ensure alignment.
3. Did you find a piece of pipe that is the same ID as the planet assembly
OD?
4. Lubrication?
5. Are you going to be able to incorporate a CS governor?
6. From experience I dont like aluminum welds for structural, fatigue
susceptible joints. I have seen to many break. If you are using aluminum
pipe for the shaft, the shaft/ flange connection wont be easy. You stated
that Tracys shaft was unnecessarily heavy. Maybe so but I doubt it would
break in my lifetime. Isn't that worth a couple of lbs? The Lyc/ Cont prop
ends of the crank are around 3" in diameter- with the bending moments of
this large diameter, it is unlikely that the shaft would fail here. And,
with all the work to make the engines lighter there must be a reason for
this large, long, heavy, expensive part of the crank.


Lots more questions-

KA

1. No. hardened steel.

2. Yes on machine after welding.

3. Not pipe. Tube! Apples and oranges. The tube will be machined
to final size.

4. No oil pressure required as all bearings are anti friction bearings.
Less oil is needed and at low pressure.

5. No. We have to keep the cost down to make it available at all.
High power to weight ratio 2 place  experimental s don't need a constant
speed prop. A P-port is much cheaper and worth 50 more HP. A p-port
is cheaper by itself than a side port engine due to additional complexity
of the four or six runner intake manifold. Set the fixed pitch prop for cruise
and take off will be adequate.

Bush planes and sea planes are another matter. In that case NOS is a cheaper
solution :) NOS does not hurt an extremely robust rotary engine like
the Mazda. Learn how to drift up to the dock with out reverse :)
If you insist use an electric prop.

I'll build those two if we get 5 people to put up $5000 each.

6. There are no aluminum parts subject to fatigue in the Ross design.
The Ross design has been used since 1973. There is a turbo 3 rotor
Lancair ES with a Ross gear box. There are probably more Ross gear
boxes out there than Tracy gear boxes. Tracy's too heavy truck axle shaft
was designed for truck vertical shear loads and low cost. There are
vertical shear loads in a PSRU.

The Lyc crank is not 3 inches in dia. About 2 and 3/8th. It is done that
way beacuse the necessary main bearings are the same dia. Cranks are
engineering night mares because of the off set rod journals.

It is easy to forge the whole thing in one piece. The long front part
is designed to take the bending load imparted to the shaft by a 50 pound
metal prop gyro reaction load. Get a copy of The Sky Ranch Engineering
Manual and read up on it.

The Lyc shafts  are not solid. They are drilled out from the prop end.

Also get a copy of Formulas For Stress and Strain. By E. Roark.

I'll be glad to discuss it with you.

Paul Lamar