In this tutorial we will learn how to stear the wheels using the toy car reactor in 3dsmax and make a donut, very simple, very quick.

First, create a Box that will be your car, some cylinders that will be your wheels and a plane that will be your surface:

Now, go to helpers, create a toy car, select your “car” as the chassis and ONLY the 2 rear wheels as wheels, then, check Spin wheels and choose velocity 50 and gain 50.

Now Create another Toy Car, Select as Wheels the front wheels, check spin wheels, velocity 10, gain 5, and TURN the car reactor in the horizontal axis so it will follow naturally the exact angle as the wheels are turned. The wheels were already turned before, but you can turn them in any moment you like, as long as you turn the second toy car too.

Now we go to the reactor menu on top and choose Open Property Editor - For the Car we choose a mass of 40, for each wheel a mass of 5 and for the plane itself a mass of 0 but dont forget to change it to “concave mesh”.

Now create a Rigib Body Collection from the reactor menu and add everything except the toy cars there.

Go to utilities (the little hammer on the top right corner and preview your animation, and after, you can render)!

toycardonut1 - Click here with the mouse right button put to save as and watch the video

Reactor is a powerful tool to creat animations in 3dsmax, but today we are going to use it to model a flag.

First thing we are going to do is model a wall, a pole, and a plane with a decent amount of segments so that the flag will not look like a broken plastic board or something =P

Now we are going to select our flag and from the modifiers panel we are going to select “reactor Cloth” for it:

You dont have to worry much about the parameters of the flag in this case, now go to the reactor menu, choose create object and then Cloth Collection, add your flag on this collection:

Now using the reactor cloth you will select the vertexes which you want to be hanging and click on fix vertices, this will allow the flag to be hanging as if it was hanging on the pole

Create now a rigid body collection and add your pole and wall into it. Now go to the reactor menu, open property editor, select your flag and give a mass of 5 to it, now select your wall and choose Concave Mesh instead of Mesh convex Hull.

Texture the flag as you like, now click on the little hammer on the right side menu and go down to reactor. Preview your animation and if everything is nice, create the animation

Now choose one frame in which your flag seems to be resting and convert it to Editable Poly, and here’s the result:

Soft selection is a very powerful tool for modeling in 3dsmax, it allows you to select one vertex/edge/polygon and as you modify it, it affects the whole area of polys around it, it is really great.

So first go to the extended primitives to create a chamfer box, make it sure it has a good number of  width and length polys so you can handle the soft selection better, your chamfer box shall look like this:

Now convert it to an Editable Poly, Select Poly and then Check the Soft Selection Box, as it is in the right corner of the image:

Notice that i already have selected the polys i will move inwards the cushion, the soft selection falloff is set to 10, which will determine the area of polygons afected, pinch and bubble are parameters that will determine the way how gradually the soft selection will affect the area polys around your selected polygon.

Now in this image you can already see how i moved the polygons inwards the cushion and the how the soft selection made a gradual and soft movement to happen.

Now i created spheres and scaled them so that they can serve as buttons for the cushion

All you have to do now is apply a nice leather material and here is your final result:

That’s it, Good luck!