Abstract: Musical percussion instrument of the drum type includes tensioning rods fitted at circumferentially spaced locations about the periphery of the drum. The drum includes a cylindrical shell with metallic rims fitted onto the outer edge of the shell. Each rod has a tubular central portion and threaded bolts screw-fitted into the outer end of the tubular portion. The outer ends of the rods are received by brackets which extend outwardly from each of the rims in circumferentially registered relation. A support post extends radially outward from the shell of the drum at a location corresponding to each tensioning rod and the outer end of the post engages the rod to brace the same. Each post is affixed to the shell at a vibratory nodal point which, as measured from the adjacent end of the shell, is approximately one-fifth the overall height of the shell.

Abstract: Machinable foams having improved solvent resistance are prepared from a styrene-acrylic acid copolymer.