Blender extrude: the E key, the Alt+E menu and the mistakes to avoid

Extrusion is one of the basic moves of modelling in Blender. It duplicates part of the mesh and connects the copy to the original with new faces: a square becomes a box, a circle a cylinder, an edge a section of wall. This guide covers the E key, the variants in the Alt+E menu, extruding to the cursor, the Solidify modifier as an alternative, and the mistakes beginners make most often.

Extruding in Blender in five steps

1. Switch to Edit Mode: select the object, then press Tab.
2. Choose the selection mode with the number keys along the top of the keyboard: 1 for vertices, 2 for edges, 3 for faces.
3. Select the elements to extrude.
4. Press E: the new geometry follows the mouse.
5. Confirm with a left click or Enter. For an exact distance, type the value on the keyboard before confirming: E, then 0.5 and Enter.

The toolbar on the left of the 3D Viewport offers the same move with the mouse through the Extrude Region tool, along with the variants Extrude Manifold, Extrude Along Normals, Extrude Individual and Extrude to Cursor. The Blender shortcuts guide lists the other Edit Mode keys.

What the E key does depending on the selection

The same key gives a different result depending on what is selected. The principle stays the same: the elements are duplicated and stay connected to where they started.

For faces, the extrusion follows the average of their normals by default, that is the direction they face. For vertices and edges, you give the direction with the mouse or by locking an axis.

Blender also distinguishes two cases for faces. On an isolated plane, whose edges each belong to a single face, the original face is kept and a copy moves upwards: you get a closed box. On a face of a cube, the face is simply moved and connected by new sides, without leaving a hidden face inside the volume. This is what keeps the mesh closed and clean, extrusion after extrusion.

Constraining the extrusion to an axis

During the extrusion, the X, Y and Z keys lock the movement to an axis:

• One press uses the global axis of the scene.
• Two presses use the local axis, that is the average of the axes of the selected faces.
• Three presses remove the constraint: the selection moves freely.

You can also hold the middle mouse button after starting the extrusion: Blender shows the three axes and keeps the one you point at when you release. By combining an axis and a value, the extrusion becomes exact: E, Z, 2, Enter raises the selection by 2 units along the global Z axis. The - key negates the typed value, to extrude downwards.

The Alt+E menu: all the extrude variants

Alt+E opens the Extrude menu, also found under Mesh, Extrude. Its content depends on the selection: the face commands only appear if at least one face is selected.

Extruding along normals

With Extrude Faces Along Normals (the Extrude Along Normals tool in the toolbar), each vertex follows its own normal instead of a common axis. On a curved surface, extruding outwards therefore enlarges the faces, as if the object were being inflated. The Offset Even option changes the rule: off, each vertex moves the same distance; on, each face does. You toggle it during the extrusion with S or by holding Alt. To move vertices along their normal without extruding anything, the neighbouring tool is Shrink/Fatten, on Alt+S.

Individual faces

Extrude Individual Faces treats each face as if it were alone: on a grid of selected faces, you get as many small separate blocks instead of a single raised platform. It is the command for studded surfaces, keyboards and patterned facades. Combined with Inset Faces (I), it gives regular relief in a few seconds.

Extrude Manifold

Extrude Manifold works like Extrude Faces, but with the Dissolve Orthogonal Edges option turned on by default. When you extrude into a volume, Blender cuts and removes the neighbouring faces instead of leaving faces that pass through each other. To cut a groove in a plank or a window in a wall, it is the variant that leaves the cleanest mesh.

Extrude Repeat

Extrude Repeat repeats the extrusion several times in a row, moving away from the viewpoint. Its settings are Steps (the number of extrusions), Offset X, Y and Z (the gap between two extrusions) and Scale Offset (a multiplier for that gap). It gives the best results from a front, side or top view in orthographic projection.

Extruding to the cursor with Ctrl+right-click

Ctrl+right-click (Extrude to Cursor) creates geometry where the mouse pointer is. What it does depends on the selection:

• Nothing selected: a new vertex appears under the pointer. Since the screen is two-dimensional, Blender places it at the depth of the 3D cursor.
• One vertex selected: each Ctrl+right-click adds a vertex connected to the previous one by an edge. It is the fastest way to draw an outline point by point.
• Two vertices connected by an edge: each click creates a four-sided face towards the pointer. Blender rotates the last edge to soften the angles; Shift+Ctrl+right-click prevents this rotation.
• Three or more vertices: the selection is extruded towards the pointer, as with E.

This extrusion follows the plane of the view. So work in an orthographic front, side or top view (Numpad 1, Numpad 3, Numpad 7): in free perspective, the direction becomes hard to predict.

Adjusting an extrusion afterwards

Right after an extrusion, the Adjust Last Operation panel appears at the bottom left of the 3D Viewport, and F9 reopens it. You can correct the operation there without redoing it:

• Flip Normals flips the normals of the new faces when they point the wrong way, which happens depending on the direction of the extrusion.
• Dissolve Orthogonal Edges merges the new faces with the existing ones when together they form a flat surface.
• Orientation chooses the extrusion axis.
• Offset and Offset Even, for extrusion along normals, set the distance and how it is distributed.

The Mirror Editing and Proportional Editing options in the same panel are of little use here: they move elements without extruding them.

Adding thickness without extruding: the Solidify modifier

To thicken a whole surface, such as a wall, a piece of fabric, a bottle shell or a leaf, the Solidify modifier is often more practical than an extrusion. It adds the thickness without touching the original mesh, and the thickness can be adjusted at any time. Its main settings:

• Thickness: the thickness.
• Offset: from -1 to 1, places the thickness on one side or the other of the original surface, depending on the direction of the normals; at 0, it is centred.
• Even Thickness: in Simple mode, compensates for sharp angles to keep an even thickness.
• Fill (Rim section): closes the edges between the inner and outer faces.
• Mode: Simple by default; Complex handles difficult cases, such as edges shared by more than two faces, but calculates more slowly.

Watch the scale: Solidify calculates the thickness in the object's local coordinates. If the object has been stretched more in one direction than in another, the thickness varies from one side to the other. Apply the scale in Object Mode (Ctrl+A, Scale) before setting up the modifier. The guide to 3D printing with Blender shows how to use Solidify to get a printable wall.

Common extrusion mistakes

Duplicate faces after a cancelled extrusion

This is the classic beginner's mistake. Pressing E then cancelling with a right-click or Esc only cancels the movement: the new faces really exist, lying exactly on top of the old ones. They are invisible, but they cause blotchy shading, bevels that fail and distorted subdivisions. Two remedies:

• Ctrl+Z straight after the cancelled extrusion;
• otherwise, select everything (A), then M and By Distance, or Mesh, Clean Up, Merge by Distance. Vertices closer together than the merge distance (Merge Distance) are joined into one.

Flipped normals

An inward extrusion or a series of extrusions can flip some faces. Turn on the Face Orientation overlay in the Overlays menu of the 3D Viewport: the back of the faces shows in red. A red face seen from outside is wrongly oriented. Fix it with Flip Normals in the extrusion panel, or select everything and press Shift+N (Recalculate Outside).

Extruding a whole closed volume

Selecting all the faces of a cube and pressing E does not make the cube bigger: Blender creates a copy that moves, with no connection to the original. To enlarge a volume, use scaling (S) or extrusion along normals.

Uneven thickness with Solidify

If the thickness changes from one face to another, the cause is most often an unapplied scale, or normals that do not all point the same way. Apply the scale, recalculate the normals, then set Thickness again.

Going further

Extrusion combines with a few other tools for most modelling work: the loop cut (Ctrl+R), the bevel (Ctrl+B, see the Bevel modifier entry, in French) and Inset Faces. The 3D modelling guide presents the construction methods, and the low poly guide shows a whole style built almost entirely with extrusions.