Blender 3D: Noob to Pro/Deforming Meshes using the Curve Modifier

Setting up your Mesh

While this example will be done with a cone primitive, you can use the default cube or another shape of your choosing so long as it can be loop subdivided along the axis you wish to curve. Delete the default cube if you're not going to use it as your base mesh, and add your chosen primitive. In this example, we'll be using a Cone.

A basic cone in Edit Mode

• Set your view to the X-Y Axis (Top View) by pressing NUM7, the 7 on the keypad.
• Press SPACE > Add > Mesh > Cone
• A smaller number of vertices are needed, since this cone will become just the tip of the finished shape.
• Left Click and drag to reduce the number of vertices to 12, then click the Ok button. (Note: On newer versions of Blender you will have to hit F6 to get to this option.)
• Press TAB to enter Edit Mode, or choose Edit Mode from the bottom of the 3D viewport.
• Switch views to the Z-X Axis by pressing NUM1 (1 on the keypad). Your screen should now look something like the picture at left.
• If your cone is selected (one or more faces are pink, one or more vertices are yellow) press AKEY (Select/Deselect All) until they are deselected.
• Select the point of your Cone with the RMB and drag it upwards with the blue arrow. You can hold down the CONTROL key if you want to contstrain the scaling to set units. For this example, 5 squares of height were added to the cone.

Extruding the Cone

Extruded cone

• Still in Edit Mode, press the NUM8 repeatedly to rotate your view to the underside of your cone. Select the center vertex of the circle, and hold down CONTROL, then press the +KEY on the keypad. This will select all of the adjacent vertices of the base. (You could also select the whole cone AKEY and deselect the top point by holding down SHIFT and selecting it with the RMB to achieve the same effect.)
• Go to front view by pressing NUM1
• Extrude the base of the cone by pressing the EKEY and choosing Region.
• Pull the new vertices away from the cone a distance and click the LMB to set them in place.
• Press the SKEY and widen the new base of the cone a bit.
• Continue extruding the cone, widening the base after each extrusion until you have at least 5 segments. The more segments you have, the smoother your curved cone will be.
• Another way of adding segments is with the Loop Subdivide tool. CONTROL + RKEY to bring up the purple placement ring, then LMB twice to add a subdivision.
• You may find that your cone is quite large indeed now, so switch back to Object Mode (TAB) and resize it with the scale tool. While you're in Object Mode, try stretching the cone out a bit to make a nice long needle.

Making a Curve

• In Object Mode, Z-X orientation (NUM1), make sure you have nothing selected and press SPACE > Add > Curve > Bezier Curve
• Rotate your curve 90° (holding down the CONTROL key to make it rotate in 5° intervals) Note- or just R-KEY and then type 90, so that it lines up with your cone. Move it off to one side so that its not hidden by your cone.
• Grab the center vertex of each end and adjust its rotation (RKEY) until you have a nice shallow dome shape.
• Scale the curve in size (SKEY) until it is larger than your cone.
• Look at the panel below the 3D space, you should see the Editing panel is selected (F9KEY) Just below the panel buttons will be a window called Link and Materials. If your curve is selected, you will see a box with OB:Curve in it. This means the name of the curve is "Curve". This is important because that exact name is needed to deform the cone.

Applying the Curve to the Mesh

Modified cone

• Select the cone in Object Mode. In the Editing panel window (F9KEY), the rightmost panel has two tabs, Modifiers and Shapes. Choose the Modifiers tab if it is not already selected.
• Click the Add Modifier button and choose Curve from the popup list.
• In the OB: box, type the exact name of your Bézier Curve (it will be "Curve" without the quotations if you left it as the default.)
• Notice the six buttons underneath the OB: and VGroup: boxes (in the Modifier Panel). They are X, Y, Z, -X, -Y, -Z. They affect which plane the curve deforms. For this example, you'll need to select the Y button.
• Move your Cone so that it overlays the curve in the 3D space screen, and notice how it follows the Bézier Curve.
• You can modify the Bézier Curve as well as the cone repeatedly until you are happy with the design.
• If you switch to Edit Mode, notice that the cone returns to its straight orientation.
• To apply the deformation to the mesh permanently, in the Modifiers panel, click the Apply button next to your Curve modifier.