The guy who built my mount is Ed Heishman. His contact
info is in my web
page somewhere in chapter 23. He's made at least one other
mount for a Cozy
builder since he made mine.
As far as the structure of the mount goes, Ed seems to
know his stuff. He
designed the mount with the weight and G constraints in
mind. You cant see
it too well in the picture, but the support tubes are in a
triangular
configuration which (says Ed) should do the job without needing any
additional tie-in supports. We'll see.
I expect Ed would just need the positions of the mounting
points and thrust
line to make a mount for another plane. Note mine is a 3rd
Gen turbo. The
mount for a 2nd gen might be a bit different.
By the way, on the Cozy IV there is not quite enough room
for the stock
water pump. I'll need to lower it by maybe an inch. The
alternator and oil
filter fit under my cowl. Just.
Regards,
John Slade
What Ed said is correct in the plane of the triangles.
It is 90 degrees to the plane of the triangles that the mount tubes
might crack near the engine. If it were not for the rubber
bushings the
mounts
in the firewall bolted connections would complete the
triangles in all
planes
and this would not occur. As you might be able to discern I
am losing
a bit of sleep over this.
It would be fairly easy to remove the paint and weld in the missing
support tubes tying all four mounts together.
If not keep a close look out for cracks.
Here also is a picture of Perry's version. He got it right.
Paul Lamar
Guys, slow down: John Slade's mount is per Tracy's design
and made by Ed
Heishman. Tracy never had any problems with his mount, but
does not mean
that Paul suggestion is not valid. I may try it on my mount.
Bulent
Come on Bulent. Tracy never used rubber bushings in the
firewall....did he?
That was my idea and I say it needs bracing tubes. If you bolt it
rigidly to the firewall you don't need bracing tubes as the firewall
serves that purpose. Then you will need rubber bushings down
near the engine
... won't you? :-)>
Paul Lamar
The bushings never crossed my mind Paul. I was talking about the basic
design with aluminum plate sandwiched between the engine and
oil pan is from
Tracy's book. I just may install my bushings down by the
engine. Here is how
we started on John's engine. The false firewall and flanges you
see with the
rubber bushings I made for my mount, but John got to them
first. I have to
start from scratch again on mine.
Bulent
Paul said:
It is 90 degrees to the plane of the triangles that the mount tubes
might crack near the engine.
I dont want to fall into the mistake of protecting the design, just because
its what I've got but...
The plane of the triangles is NOT 90 degrees to the engine. There is a big
component in the plane 90 degrees to the engine. Look more closely at the
picture and you'll see what I mean. However... once I have everything
installed I'll take a look at how the extra tubes would fit, and have
another talk to Ed. Thanks for the input.
John Slade
That is not what I meant John. Take the mount off the firewall in
your mind for a moment and put some virtual loads on the rubber bushings.
Notice how the tubes of the triangle can then bend in direction that
are 90 degrees to the plane of the triangles. It cannot happen
if the the motor mount is bolted rigidly to the firewall.
This happens when it is mounted to the firewall as well because the
rubber bushings can deflect in all planes.
The best thing to do is build a 1/4 scale balsa model out of 3/16 square
balsa sticks and bend and twist it. This is the fastest way to discover
flaws in space frame designs.
Paul Lamar
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