SERIOUSLY,  I have questions.  If we hollow out the e-shaft to run oil
through it, wouldn't we be making the e-shaft intrinsically _weaker_ as
well?

How much _can_ we hollow out a stock Renesis e-shaft (just for example)
without weakening it?  (Yes, I know, the article is talking about a _new_
e-shaft, hydroformed to spec.  _But_ if we want to apply to concept to
existing oil-cooled rotaries as Paul suggests, I ask so that we would not be
required  to make expensive, brand new e-shafts for perfectly good existing
engines.)

If we hollow out the e-shaft, would we not be also required to make the
diameter of the e-shaft bigger?  If so, how much bigger?

How would making the overall diameter of the e-shaft bigger affect the
engine's eccentricity ("stroke")?  How much bigger can an e-shaft be made
until it negatively affects the engine's functioning?

What other questions should I be asking, and have not?

And of course, how do we know, and how do we know we know?

Thanks,

Les Nordman :-)

Most of the stress is near the surface of any shaft. Most of the stress in
the e-shaft is in the fillet area  between the main bearing and the
eccentric lobe. It does not need to be any bigger. Nobody has every broken a
properly balanced Mazda rotary engine E-shaft despite generating up to 800
HP so obviously it is over designed and can be hollowed out without
problems. The same thing cannot be said about piston engine crankshafts that
all crack sooner or later.

Paul Lamar ...No rotor no motor.


How about EDM an E-shaft for an existing design for testing?????
Just a thought.
C. Smith

Can you EDM such a complex hollow shape?
How is that done?