I am a couple of months into creating a 3D CAD file to make plastic gas tanks that fit common beach cruiser bikes frames, have the base design .STL file and sent it to this Purple Porcupine rapid prototyping service and got this quote back to make 1 gas worthy gas tank to fit a 29" Macargi.
So much for prototyping with the right material.
$6,816.78 to print out one tank.
Total does not include tax and shipping.
I guess I shouldn't have said I was from NASA? hehe ;-}