Sounds like they would fit inside 1 1/2 " PVC pipe to make a version of the demo where
mass is concentrated at the center of one pipe while in anogher pipe the mass is out at
the end. Since they already have holes in the ends, one need only drill through the pvc
at the right spot.
--
Mike
===============================================================
Mike Moloney http://www.rose-hulman.edu/~moloney
moloney@nextwork.rose-hulman.edu
Dept of Physics & Applied Optics (812) 877 8302
Rose-Hulman Institute of Technology Terre Haute, IN 47803