More results:

Originally I was looking at the geometry of a leaf spring vertical (not 
horizontal) having a "pendulum" that was essentially horizontal.  Today I 
took a quick look at the geometry of a vertical pedulum, i.e. one suitable 
for a horizontal instrument, the configuration currently being discussed.

The results using my CAD program were similar, in that the tip of the 
pendulum traced a circle with very little error.  However the center of 
that circle was no longer near the crossing point of the flexures, but was 
located within the upper pivot rod, about 1/3 of its diameter down from its 
axis.

More analysis obviously needed.

Brett

At 02:53 PM 10/23/2005 -0600, you wrote:
>Hi all,
>
>Chris Chapman recently stated in a private email that he thought a crossed 
>rod hinge
>suspension would have less friction/dampening than a ball bearing 
>hinge...and he is
>so very right!



>
>Take care, Meredith Lamb
>


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