How to Add Faces Using the 'F' Key in Blender

To add more faces to a cylinder in Blender using the method shown in the reference, you can select vertices, edges, or faces and use the Face (F) key to create new faces or fill existing gaps.

Adding faces to a cylinder often involves working in Blender's Edit Mode. You can create new faces between selected vertices or edges, or fill loops, depending on your selection.

The most direct way to create a face between selected geometry elements is by pressing the 'F' key. This is particularly useful for filling holes or creating planar faces within your mesh.

Steps to Add Faces

1. Select Your Cylinder: In Object Mode, click on your cylinder.
2. Enter Edit Mode: Press the Tab key to switch to Edit Mode. You'll see the vertices, edges, and faces of your cylinder.
3. Choose Selection Mode: At the top of the 3D Viewport, you can choose to select Vertices, Edges, or Faces. For creating new faces, Vertex or Edge selection is often used, as shown in the reference.
4. Make a Selection:
   • To create a face from vertices: Select three or four vertices that lie on the same plane. As the reference states, you can "select just a few of these."
   • To create a face from edges: Select two parallel edges.
   • To fill a loop: Select a loop of edges or vertices around a hole.
5. Create the Face: Press the F key. Blender will attempt to create a face based on your selection.
   • As mentioned in the reference, selecting a few vertices and pressing 'F' "is going to add a face to those".
   • Similarly, if you "add another vertex" to a selection (implicitly suggesting enough points to form a face) and press 'F', you "get a face that fills" the area.

This method is powerful for mending holes or manually adding faces in specific areas of your cylinder.

Practical Examples on a Cylinder

• Filling the Top or Bottom: If you delete the top or bottom face of the cylinder, you can select the loop of vertices or edges around the opening and press F to fill it with a single face (called a " ngon").
• Creating Faces on the Side: Although cylinders are typically made of quads on the side, if you deleted some faces, you could select the surrounding vertices or edges and press F to recreate them individually or in groups.
• Splitting Faces (Less Common with F): While F primarily creates new faces or fills holes, other tools like the Knife tool (K) or Loop Cut (Ctrl+R) are more common for adding faces by splitting existing ones. The reference focuses on using F to create a face from selected elements, not split.

Key Action Summary

Here’s a quick look at the core action based on the reference:

Action	Description	Result
Select N vertices/edges (N=3 or 4 for polygon, 2 for edge creation*)	Choose the points or lines for the face	Prepares the selection for face creation
Press F	Execute the Face command	Creates a new face from the selection

*Note: Pressing F with two vertices creates an edge; with two edges that share vertices, it can create a face.

By using the 'F' key after selecting the appropriate geometry on your cylinder while in Edit Mode, you can effectively add faces where needed, as demonstrated in the reference.