We shall learn here how to create a tornado in 3d max.
Although it is about material of tornado therefore, material editor is the main key to create its material. To set the material of tornado, open any empty slot from material editor.
Make sure that it standard material mode and check the 2-sided box. Scroll down material editor and check the specular level and glossiness are at 0 level. Click on map panel, check the opacity and then click on none button. It will open in map browser, here choose Gradient Ramp. Now back to material editor and adjust the level of Gradient Ramp parameter with color chooser. Choose the Gradient type as Radial. Apply the selection to empty slot so go to material editor and click on button assign material to selection. Take a test render at that time and you see that it needs couple of changing yet. Right click on the object and choose object properties. Check the box of motion blur and then hit OK.
Now go to render set up and set the object motion blur parameter. Take a test render again and you see it will more actual and accurate than previous. Still in render the edges of Tornado are little bit rough so you can edit it in its setting as much you need.