I'm very new at CNC routing. Lots to learn. I am trying to machine a full scale replica of a pre WWI propeller. See attached picture (a couple of support ideas shown). The thickness is a little over 5". Prop length around 8' and 14" wide. I'll prototype at probably 1/2 scale but am designing for full scale. Because of the blade pitch, I will need to do a cut depth of over 4" in the roughing pass. I'm thinking I'll need to buy some expensive 6" end mills and ball end cutters with a reduced shaft diameter for this project. Is there any other way to do this with shorter bits? If I go with long bits, what diameter would you recommend? Considering the length, I was thinking 3/8 or 1/2"