>
     > Tony,
     >     I have Tracy's 2.85:1 redrive and it has a fully functional,
    light
     > weight, proven, cost free mount. The original RWS mount that
    comes with the
     > drive. I am not trying to knock what you are trying to achieve
    here but I
     > for one would have trouble justifying $1000 to replace the
    original. Yes it
     > looks cool but then again I don't have a problem with the looks
    of Tracy's
     > design, I want to fly it, not look at it. If someone else wants
    to look at
     > it then they will have to find which one of a thousand lakes I
    intend to
     > explore once I'm in the air. If Paul Rhino'd  a bell housing that
    could be
     > fed into a CNC milling machine which would then turn out a real
    light
     > aluminum housing I might consider that, sure it would be a big
    chunk of
     > aluminum to start with, but a thousand dollars ? The huge pile of
    schwarf
     > going to the recycler would make it almost free :)  I don't think
    this could
     > be more than a few pounds lighter than the original and truth be
    told I
     > would be better off losing that weight from one of my man boobs
    anyway.
     > Perhaps though there are more people on here with the extra
    ca-ching than I
     > realize. Best of luck to you.
     >
     > John


    Are you saying you don't think the carbon fiber version would be much
    lighter than the Tracy 2.85:1 or that a milled aluminum housing would
    not be much lighter?

    How much could you remove from the existing aluminum housing?

    Could you mill out holes and cover them with plastic or composite?

    Could you mill out some kind of fractal honeycomb pattern?

    -Jeff


    BTW Tracy's current system with 1/2 inch thick adapter plate, four
    inch long 10 mm bolts and aluminum spacers weighs around
    8 pounds.

    I like your idea John. NC mills are getting more numerous
    and faster so the cost is coming down. I would start
    with a slab about 16 inches high and 30 inches long and
    three inches thick. Wall thicknesses would be an 1/8th of an
    inch or less.

    Paul Lamar ...No rotor no motor.


Composite or milled Aluminum, it seems reasonable to design in bosses
for motor mount hard points.  Then the physical details (width/fore-aft
location) of the mm could be left to the builder.


Regards,

Matt-

That would probably save a lot of scrap.

Here are some old 3Ds of that idea.
We have been kicking this problem around for years.
It is hard to beat the low weight and relatively low cost
of the stock high pressure bell housings.