Oh! We just got our first 4 rotor-housings back from machining, 2 of
them  are going next week to have the epitrochoid plasma-sprayed
(Iron/Iron oxide) and the other 2 to have it NiCaSil-treated, for
testing these 2 possibilities.  After Sun'n Fun, we'll beat the hell

out

of them and see what gives.  I attach 2 pictures, one of a Mistral
casing compared to a Mazda one to show some of the differences and
another one of ME housings viewed from different angles.  Do you have
suggestions on the seal materials we should use?

Best regards,

Francois Badoux

OK. Creavey teflon encapsulated silicone O rings. Best we have found so
far.
Good to 500 F.

Paul Lamar

I was thinking of the material of Apex seals, to find a good match to
the new surface.

Francois

Those are tricky. My guess is Inanetti ceramic apex seals but I am
not 100% sure they are silicon carbide or if they will work on nicosil. 
I think they are silicon carbide. Mazda uses special cast iron that has been 
heated with a laser and then chilled with liquid nitrogen. Super hard surface 
finish. All apex seal material is highly dependent on the type of surface 
they are working on. Perhaps you can find out what Diamond Engines is using 
on their nicosil plated rotor housings.

BTW Francosi I think you could generate some cash flow if you sold some reasonably priced
aluminum end housings with steel wear surfaces. My guess is around $500 each would 
sell. Racing Beat is selling theirs with questionable coating technology for $1200 each.
(Not detonation gun coated.) Not selling well either.
 
Paul Lamar
 
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