Paul,
Didn't I suggest that a little while ago ? It was poo-pooed then !
While your at it look at doing rotor housings with peripheral ports
and Intermediate/end housings - not joking !!
The castings are the best I've seen for sand castings, they looked
more like pressure die cast to me.
You will find they will be using silicone in the aluminium to help
 the pour.
Would you get an effective wear surface on an aluminium rotor
housing ????
George (down under)

Things changed George. I went to Sydney and looked at some that were
too heavy and they wanted $5000 US to do a bell house pattern.
Now Tom Kendall is up to speed on pattern making and I have found
a foundry out here that can do thin wall castings to cut the weight.

I think a cast aluminum end housing is too expensive to make.
The pattern cost would be big bucks with several very complicated
core boxes. There is a reason RB Jim is charging up to $1700 each.

Don't know about the silicon aluminum. I think the GM Vega engine
had a lot of problems with it. All I know is just about everything
has been tried and most have failed. Detonation gun coating with
carbide is a safe bet but too expensive.

BTW I wonder why nobody is respecting the cheap two piece
end housing design. How can you beat a low tech replaceable hard steel
wear surface that has been nitrided? The 4130 steel plate can be laser
cut to shape at low cost. I was just thinking that I need to put
that up on the web site.

Paul Lamar

Paul,
Pity about the rotor housing not being possible, having them made with PP
would be a winner. How much would it cost for the DG coating on a rotor
housing at a guesstimate?

My wild ass guess is $500.

BTW a lot of die cast have silicone in the aluminium - makes it run easier
especially for thin areas.

We use 356 T6 do you know the composition?
 

The Intermediate and end housings with the plate was what I was referring to
perhaps someone will bite the bullet and run a test engine - I've always
liked
the idea, taking into consideration comments on different rates of expansion
etc.

Can you draw a line on your cut down plate and give an idea of where you
 would run the seals and bolt attachment points.

I don't follow you here.

You have your barry mount running horizontally, in this drawing, rather than
vertically (as in the plate design) - any reason for that ?

George (down under)

That is primarily because the engine would be cantilevered off the front
end housing with a significant bending moment. So the rubber axial loads would be rather
high. Common practice in AC motor mounts prior to dyno focal.

Secondarily it is simple.

Paul Lamar
 
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