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
Larrytackled 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
turnedover. 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.
The reality is that machining two molds would have been just as, if
not easier than doing the full pattern in one pc. It would have ment
twice as much wood, but the setup's would have been way easier.
I was going to suggest it, but knew it was not the 'normal' way of
things so I kept my mouth shut.. anyway.. I can't wait to see the
cast parts!
Jarrett
Thanks for all your help on this Jarrett. Jarret converted the Rhino
IGES
files to Solid Works files. In some cases starting from scratch I
think.
Thanks again Jarrett.
Paul Lamar
No problem Paul, it was fun.. in this case the file was created from
scratch.
Btw, I can now open Rhino files right into SW. I've not tried it but it
is
supposed to work just like an IGES.
I can't wait for the next project :-)
Jarrett
Jarrett,
I've tried the Rhino to SW converter and it works great. The parts were
coming in as "imported" solids but I think the latest version is
supposed to take them in as parts.
Bill Jepson
The news letter will be shut down for an OSH week.
Paul Lamar ...No rotor no motor.
Jarret, Larry,
I am taking my Bell 47 housing and Luce semi auto. bell housing down to a
company that does die casting for us and they have a machine with a metal
probe that can basically probe objects and create a file in SW.
So I don't sound like a total fool can you tell me the name of this
technology. 3D scanner?
Doug in Japan
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