MAXON Computer Cinema 4D Tutorials: How to Extrude Edges

Tips & Techniques - Modeling

Modeling:
How to Extrude Edges

Works with:
R8 Requires:
Version 8+

Extrude was originally for polygons only. But now with the new Edge Tool, you can select and extrude edges as well.

Step 1: Create a Cube (Objects=>Primitive=>Cube).

Step 2: Make Editable (Structure=>Make Editable).

Step 3: Select the Edge Tool and select an edge.

Step 4: Select Extrude from the Structure menu. There are two ways to extrude. You can drag the edge interactively in the editor or you can use the settings in the Active Tool dialog if you need precise control.

You'll notice that when you extrude by hand, it forms a triangular polygon. By holding down the Shift key while pulling, you can control the length of the extruded edge without affecting the base width. By holding down the Ctrl key while pulling, you can control the base width of the extruded edge without affecting the length. However, the smaller the width, the less likely the edge will be allowed to extrude again since it may create an illegal polygon. This is when 3 polygons share one edge.

Step 1: Create a Cube and then select Make Editable from the Structure menu.

Step 2: Go to the Polygon Tool and select and delete one side of the cube.

Step 3: Go to the Edge Tool and select one of the open edges.

Step 4: Go to Extrude in the Structure menu. Now hold down the Alt key and click and drag to extrude the open edge. You'll see that it creates a single polygon. Now release the Alt key while still dragging with the mouse. You will be able to rotate the polygon to determine the angle of extrusion. Once you've acheived the desired rotation you can press the Alt key again and continue extruding without creating additional polygons. Be sure to hold down the mouse key during this entire process.

The Edge Angle field in the Active Tool Manager is the default angle at which the edge will be extruded.

You'll also notice that when you rotated by releasing the Alt key it snapped at 15-degree angles. This can be adjusted using the Snap Angle setting. When checked, it snaps to the set angle.

For safety reasons, if you select a closed edge, hold down Alt, and then try extruding, it deselects your selection to prevent you from creating an illegal polygon. Holding Alt to extrude a single polygon is only allowed on open edges.

-Special thanks to Kai Pedersen.