From: john@sugarbit.com   
      
   Spring catalogs will list nominal spring constants but there's lots of   
   variation.  Better to measure your particular spring.  As far as I know   
   nobody publishes damping coefficients.  You could compute them from the   
   spring dimensions and the material properties but I don't think that   
   would be very accurate.   
      
   You can measure the spring constant by measuring the spring, applying a   
   known force, and measuring again.  The spring constant is the force   
   divided by the change in length.   
      
   Knowing the spring constant you can then hang a mass from it, start it   
   oscillating, measure the period and decay time constant, and calculate   
   the damping coefficient.  That way you would be including the effects of   
   the air.  Hang it from something rigid and massive, of course.   
   --   
   John Hasler   
   john@sugarbit.com   
   Dancing Horse Hill   
   Elmwood, WI USA   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)