I would like to make a steel anvil stand from some square tube from my scrap pile. I have plenty of 6" x 6" x 1/4" steel tube and plenty of 3" x 4" x 1/4" steel tube. I don't know if I should do a post style bolted to the shop floor or do the tripod style. What is the best choice of material(s) to fill the tube(s) with to dampen sound (oil, oil/sand, compressed air?). Below is a pic of the 2 anvils (160# peter wright and a 120# WBB)