Gary,

One correction to what I'd written previously.

In corresponding with Chris and re-reading Dr. Peters' paper, I have had to 
conclude that for pivots in general, as well as for other elements which 
aren't specifically designed to be velocity dampers, their resistance force 
has no reason to be accurately proportional to velocity.  I believe that 
velocity relation is needed to derive the exponential shape for the 
envelope decay.  Under some conditions air resistance might possibly act as 
a form of velocity damper, but hinges in general, probably 
don't.  Therefore, as Chris says, the oscillation decay probably isn't 
going to be exponential to any great degree of accuracy.

Regards,
Brett



At 04:07 PM 7/3/2008 -0700, you wrote:

>I have been taking my time to get my first Lehman up and running.




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