Hi Zorbit - Yes its a good read. It (the article) has come up a few times. Given no consideration on cost, carbon fibre would be my material of choice. Std modulus CF will give you 70-80GPa stiffness quite easily and intermediate modulus will be 110-120GPa and stiffer then cast iron at 1500kg/m3 plus really damp to boot. But $$$ do drive the market so until I do the next ALOX tests I'm rethinking the glass fibre stuff at 33GPa. At least I can machine GF vs alox.... Peter