Subject: MM plate
From: ACRE NL
Date: 6/26/2002, 3:19 PM


Jerry Hey wrote:

Paul,  here is our MM Plate.   We are very happy with its
appearance and
in several aspects of the narrow plate we got LUCKY.   For example,
when the engine is in position on the thrust line, the top tube of
the
engine mount will clear the muffler easily.    Secondly,  the MM
plate
is the perfect width and location to easily mount the oil cooler.
Brackets can be welded to front side of the tube thats forms the
bottom
of  Barry Mount.  (Same tube that the engine mount space frame
tubing is
welded to on the other side.)

We have  bolted up Tracy's drive and have verified all of plate
attaching  bolt holes.  Everything is a perfect fit.

One thing to be aware of is that different starters have different
diameters so each MM plate is specific to a certain starter.   The
plate
shown was cut for a Mazda starter and the hole is too large for my
Mitsobishi starter.   I was not aware of this until I got it home
last
night.

Pricing:    the MM plate with Barry mounts complete as shown in the
photos is $550.00. The wider plates will be an additional $50.00
because
they  require a second set up in a different mill.  (The mm plates
can
be any width from 20.5" to 29.5"  whatever the builder wants.)

Complete engine mounts will soon  be offered.   The universal
fixture is
finished.  Now I got to figure out how to use the thing.      Jerry

They look great Jerry. If anyone is concerned with the stiffness it
is a
simple matter to add 1/2 inch square diagonal tubing braces from
mounting bolts
to the nose of the PSRU. They are most likely stiff enough for all
but violent aerobatics.

Paul Lamar

I hate to rain on someones parade, but didnt Tracy say that mounting
on his
PSRU this way was a bad idea, or did I misunderstand him?
John Slade
Cozy IV - wiring

With all due respect Tracy is wrong.
Old message on this subject:

   Well, Tracy may or may not be wrong about this. But its his design
and
he has stated that anyone who uses this mounting scheme voids the
warranty
on the RD1. Thats enough for me and anyone considering this mounting
scheme
for the aesthetics (it does look awfully nice Jerry) should consider
how
important a warranty is to him before proceeding.

Mike Wills


It is too bad that Tracy feels that way. I personally think he is wrong
and it is a shame that such a heavy device as this motor plate cannot
be used for a motor mount to save expense, weight and time.
We will test it shortly as I am building a dyno test stand that will
subject Tracy's PSRU, this motor plate and motor mount to loads that
far exceed what it will see in an airplane. Mainly severe gyroscopic
loads due to a continuous pitching moment. I have made extensive
calculations on the stiffness of this plate and I don't think Tracy
has made any. This is not a new idea. Every racing car for the last
40 years has used a similar scheme to mount the engine. It is standard
on almost all classes of racing cars.

Paul Lamar

Mike and all,    I can't think of any reason why Tracy should warranty
anything that he has not designed, built or sold.   He warranties his
own excellent products.  That is all anyone could ask.    If someone,
such as Paul Lamar or myself   comes along and changes things, then the
warranty no longer applies.  Buyer beware!!!

On the other hand,  the MM plate was designed by Paul and I have learned
to trust his work. .   It solves a ton of problems and as you have said,
it looks good too.   I believe that having available an off the shelf
solution to hanging the rotary is a real advance for rotary movement.
That is why I got involved.   Not being an engineer myself,  I can only
say that the plate appears to be up its   task.      Jerry


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