Larry delivered the pattern by driving down from Northern California
Thursday after noon. We drove it over to the foundry today and
it passed inspection and left it there.

In fact they complemented Larry on the nice work. I am relived and
very happy.

We will have ten castings next week. Larry is building a
test rig so they will be static tested to 600 foot pounds. The same torque
will bend the flange on a Lycoming aerobatic motor so any more than
600 foot pounds does not make any sense.

Paul Lamar ...No rotor no motor.

Sorry if I missed this in an earlier post (and my ignorance):  what is the
exact technique used to cast a housing with this pattern?  Is it lost-wax,
or some other method?

Scott Gettings

Straight sand casting Scott. The foundry we use specializes in thin wall
sand castings. The lost wax process would be too expensive.

-- 
Paul Lamar ...No rotor no motor.

An interesting point Paul, and I was interested to see how you and Larry
tackled it - is that a lot of casting companies want an inner and an outer
pattern (dowel matched). That method is expensive and time consuming.
I noticed that Larry has made one pattern, which is used as an inner and an
outer ( same as the method I used). The pattern is placed flat on the back
surface ( within a frame), sand is packed around it and then it is turned
over. Another frame ( shorter) is placed over the top of the first and the
inside is filled with sand. The frames are split at the junction -
maintaining true symmetry ( inner to outer).
Copies of mast things can be achieved using this method, provided the copied
item can tolerate the 1:22 shrinkage rate i.e. difference in finished sizes.
BTW did you leave about 5mm clearance on the flexplate to
Bellhousing?
George (down under)

Yes.

Paul Lamar ...No rotor no motor.

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