I am interested in getting my foam locally in southern Ohio (and hopefully cheaper) rather than going to the usual aircraft kit suppliers. I was reading Andy Marshall's "Composite Basics"(1994 Edition) and he warned that there were two types of Dow Sytrofoam. One was the type used on the Varieze, Longez, etc. The other was what he called "bead foam" which is made by exposing the styrene beads to steam. This foam is weaker than the other Dow Styrofoam and so should not be used on aircraft. Does anyone here have a way to tell the difference in the two foams? Also when you go to the insulation store do you just ask for the Dow blue 2 pound per cubic foot foam and see what sizes they have?