>>>>> 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

That is fairly common tech. It's called digitizing. Lots of machine shops
will use a Renshaw probe [bascially a precision switch really] and using
their cnc mill's can 'touch off' points on a part to get the geometry basic's of the
part. If it's a free form 3D part, then you can get automated processes
called CMM which will move over then entire part at a pre-determined
step over [ 0.01mm or.. 0.010" or whatever you want] and touch every area of the
part. Everything the probe touches the part, it records the coord. data.

This data is then imported into some form of CAD where each of these points
is used to create a 3D model from the 'point cloud'. To my knowledge, there
is no hard, fast point and click method of getting the job done. Once the
point cloud is imported the model will still need to be cleaned up to
some extent. Both SW as well as Rhino and a few other programs
will import point clouds.
There is a new movement in this area of CAD [reverse engineering]
where lazer scanning can do the same thing at a faster speed.
There are several new companies out there who are producing
these scanners. However, currently the affordable ones have
relatively small working area's, of only a few inches
[less than 12 x 12 I believe].

I'm sure Larry has used a probe in his days as a machinist, and most
likely has some equipment to do this in his shop.
I'm finishing a mill which will have a probing cycle on it as well
as be able to do the full CMM probe cycle also.

Anyway, hope that helps!
Jarrett

BTW Larry, What is the status of the bell housing this week?

-
Paul Lamar ...No rotor no motor.

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