I wonder would a viscous fluid have any damping capacity? Supposing you could cap the ends of all the tube members and fill them with oil and sand or something. Maybe even pressurize the thing a bit with a portable hand pump like a grease gun.
If it doesn't work, don't call me and ask what to do with the mess afterwards
First you get good, then you get fast. Then grouchiness sets in.
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)