Originally Posted by ThreeDogsNE
As I understand it, aluminum has a melting temp that is too low for such use. Your second question I'll leave to a real engineer.
+1 - aluminum anywhere near the burners will soften and sag. Even thin steel can have problems. better to stick with stainless 3/16 anywhere near the heat source.
also, make sure its got space to expand. when you heat it, it WILL expand. if the ends are constrained too much it WILL deform. this is easily accomplished by have some flexibility towards the top of the stand.