Paul,
I've just gotta ask - why haven't Tracy's rubber mounts melted?

Ken Powell

You got me.

Paul Lamar

I checked a picture in his book and the rubber bushings are
no where near his engine. He used the dynafocal mount.

Paul Lamar

Let's be a bit more specific about Finn's motor mount problems.  The conical
rubber mounts did not melt.

How do you know? Did Finn take it apart at Shady Bend after I left?

The primary 'failure' (sag of the mount) is due to the aluminum conical
mount cups not being correctly fastened to the plate.  They were glued with
JB Weld epoxy and the glue joints failed in shear.  I like this stuff for
many purposes but this is not one of them.

I do agree that the 'bolt in shear' design is not a good idea.  The
Conversion Concepts mount abandoned this approach before any were sold.

Tracy Crook
tcrook@rotaryaviation.com
www.rotaryaviation.com

The 3/8 bolt is NOT in shear. It is in almost pure bending.
Conversion Concepts would have shipped the mount in question if I had
not raised serious reservations  about it in private email to them.

Paul Lamar
 
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