Paul,
On reflection, yes your right!!

However it would require some additional machining, which I was at the

time

trying to avoid.

I would require an outside (face flange) for my unit and Tracy's unit

would

require a inside face for his seal, tricky to do with a raised tube of

any

length or a insert plate (as it is now). Since that debate I've figured

out

that that all it requires is a tapered( Both Sides) Tube for the

foundry. I

would make it fairly thick for my purpose and it could be machined-out

for

Tracy's unit.

However in reality it's not dissimilar to what we have with Butch's
drawings.

Actually I would be happy to go that way as it saves me length in the
Planetary housing section.

Mine would end up similar to the Ross design.
George (down under)

What is the bottom line on your foundry ability to cast thin walls.
is 5 mm about it?

If an when I get my NC mill working I can bid on machining them for
you.
At least the ones bought in the States.

If it were me I would machine a lot of lightening holes as IMHO any
sand casting,
due to the the thick walls, would be over designed strength wise.

Paul Lamar

Paul,

On the housing thickness, I discussed this with Butch - considering the
strength requirements, the LESS DENSE nature of sand casting and considering
that the Mazda injection castings are about 5mm - we consider 5mm to be
about right, which about the limit of my sand casting supplier anyway.

However IF we could ever agree on a design and I found some partners for
injection tooling, the housing could be thinner.

How is that CNC going, I've seen it
in the background of a couple of photos, I would like one of those.

George.

I think you are being optimistic about the market George. A die
casting
mold can cost over $100,000 US. We would have to sell hundreds to make
that
pay. Perhaps in another five or ten years. I could be wrong. Maybe
only
$50,000 for the mold.

Paul Lamar
 
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