I am looking to build some leading edge slats for my bush plane and would like to use rutan method , I have hotwired out a proto type out of polystyrene and covered with graphite and was impressed with the results. However i would like to use a foam that is structural and fuel resistant. I need to know what are the choices and can it be cut with a hot wire or does it have to be milled to profile? If possible who in the northwest or somewhere close to alaska does cnc foam cutting?