Everybody,  I just talked to Atkins rotary.  They will provide as an
assembly a single rotor/eccentric/flywheel/balance weights.  Assembly
is balanced to within a gram and guaranteed to run smoothly.  The
eccentric is cast.  They make the complete single rotor engine for
marine application.    While I don't like the idea of a cast
eccentric, on the other hand it is very short and therefore very
stiff.   The price is $1500.00.
What do  you all think?   Also they quoted  $150.00 for a set of
tension bolts.      Jerry

Jerry,
I spoke to the metallurgists who tested the Rotary shaft for me( they are
aviation accredited) I suggested to them that I was considering casting some
and they suggested to me in no uncertain terms that because of porosity
problems, they could in no way recommend a cast crank for Aviation use. I
will leave it to you to make the final decision.

I have found a local chap to turn my single out of 4140, he's a neighbour
and is doing it as a favor so will cost me a couple hundred bucks. That's
not including the cost of material  grinding, heat treatment and final
runout checking and adjustment with final polishing. However I have asked
him to work out a cost (given the first is an assessment of time and method)
so that he can quote on providing the same thing to others.
I did ask Larry to consider this on two occasions, but as yet he hasn't
responded.
George (down under)

A one rotor e-shaft is not highly stressed. The same output e-shaft diameter
supports
the torque from a four rotor engine. Cast iron, if done properly, will work
fine for a one rotor. Wankel Gmbh Germany patented a hollow e-shaft hydro
formed
from thick wall steel tubing.

Paul Lamar

Guys,
At this time I am not going to do any eccentric shafts. I only have one cnc
lathe in the shop and it is booked constantly. Once I have some of the other
projects done, we will re-address the shafts.
Thanks,
Larry

Jerry,
There you go, problem solved. Thanks for responding Larry, I have all the
details if you need any - probably won't considering how simple it is.
I was figuring that a cast eccentric wouldn't be cheap and then you would
still have to do all the same things to it i.e. turn down, Grind Nitride and
polish possibly cheaper to turn it from a billet of 4140 in the first place.
I DO however like the hydroformed hollow shaft, they sure are innovative
over there!
George ( down under)


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