Using The Extrude Tool

This tutorial will cover in depth the extrude tool and all of its functions.

Set-up

Create a sphere by going to create>polygonal primitives>sphere.

Set the menu set to polygons.

And make sure you have a basic knowledge of Maya.

What Does Extrude Do?

Extrude creates new geometry from a selected component. This selected component can be vertices, edges, or faces; most commonly used is faces.

After you click extrude, Maya will use the show manipulator tool to let you set the attributes of the extrude visually.

More on that later. You can extrude multiple components at a time.

Creating An Extrude

Step one - Select the face or faces.

Step two - Go to edit mesh>extrude.

For this example, use the blue handle and move the manipulator forwards.

You can see the extruded faces.

Using The Manipulator

The manipulator connected to the extrude tool can scale, rotate, and move.

To move the manipulator, use the arrows. As you see, this will move along the surface's direction (local space). If you want to move in X,Y, Z space (world space), click on the blue dot.

Now the manipulator works like the move tool.

To scale a manipulator, click on the boxes on the tips of the arrows. These will scale along the X, Y, and Z axes. If you want to scale all axes at the same time, click on one of the cubes, doesn't matter which one, and this will put the manipulator in scale mode. Then select the cube in the center of the manipulator to scale in all directions at once.

To rotate the manipulator, click on the blue ring around the manipulator.

This enters the rotate mode and, by clicking on one of the rings, you can rotate around one of the axis.

By rotating the blue ring that surrounds the model, you'll rotate the object along the camera's axis.

What's The Difference Between Extrude And The Move Tool?

When you're using the move tool you're only moving the geometry. When you're using the extrude tool you're creating and then positioning the faces.

Anatomy Of An Extrude

Step one - Repeat the set-up and create another extrusion.

Step two - Open the attributes editor by going to window>attributes editor.

Here's how the extrude tool works: Maya will create a node called polyextrudeface. This node contains all the attributes for the extrusion. These attributes are changed by visually setting them using the manipulator.

To see this, move the manipulator handle and the attributes editor will change.

When you're using the local mode for the move tool, the local translation attributes will change. If you're in world space, the normal transform attributes will change.

Extrude's Attributes

This is a rundown of most used extrude attributes.

Translate Attributes - This is the location of the extrude in world space.

Polyextrude Curve Attributes - These attributes will be covered in the extruding along a curve section below.

Divisions - This is how many divisions will be added along the extrusion.

Offset - An offset value for the local translates.

Local Translate - This is the location of the extrude in local space.

Local Direction - The direction of the local axes.

Random - Basically makes the extrude random.

Smoothing Angle - This is in regard to the normals. Example: The surfaces edges are over 30 degrees so they are made "hard" edges. If they're less than 30 degrees, they'll be made "soft" edges.

Keep Faces Together - Explained later.

Extruding Along A Curve

Step one - Create a curve by using the create CV curve tool. When you create your curve, it should be created going outwards from the geometry.

Step two - Select the face that you intend to extrude, then hold shift and select the curve and go to edit mesh>extrude.

Step three - Open the attributes editor. The most important attribute to change is the division attribute. The extrude will look bad until you increase the number of divisions.

Here's a rundown of the poly extrude curve attributes:

Twist - Twists the newly extruded geometry along the curve.

Taper - Tapers the extruded geometry along the curve.

Taper Curve - This lets you create a visual profile for the extrude.

Keep Faces Together

The image below shows the difference between an extrude with this on and an extrude with this off.

To turn it off, go to edit mesh>keep faces together and uncheck it.

Conclusion

This tutorial has covered a lot of the main features when extruding.
Good luck.