How to Use the Fillet, CHAmfer, and BLEND Commands in AutoCAD 2014 - dummies

How to Use the Fillet, CHAmfer, and BLEND Commands in AutoCAD 2014

By Bill Fane, David Byrnes

Whereas TRim, EXtend, and BReak alter one object at a time, the Fillet and CHAmfer commands modify a pair of objects in AutoCAD 2014. Fillet creates a curved corner between two lines, whereas CHAmfer creates a beveled corner. (It’s pronounced “FILL-et,” not “fill-AY.” Saying that you know how to “fill-AY” may secure you a job in a butcher shop, but it won’t help you in a design office.)


Fillet and CHAmfer show a preview of the results of the operation as soon as you select the objects to modify. If the fillet radius or the chamfer distances don’t look right in the preview, you can change their values before completing the command.

The following steps describe how to use the Fillet command — the CHAmfer command works similarly except that, rather than specify a fillet radius, you specify either two chamfer distances or a chamfer length and angle:

  1. Click the Fillet button on the Home tab’s Modify panel.

    Fillet and CHAmfer share a flyout button; if you see a straight-line corner instead of a rounded one, click the flyout arrow to select Fillet.

    AutoCAD displays the current fillet settings and prompts you to either select the first object for filleting or specify one of three options:

    Current settings: Mode = TRIM, Radius = 0.0000
    Select first object or [Undo/Polyline/Radius/Trim/ Multiple]:
  2. Type R and press Enter to set the fillet radius.

    AutoCAD prompts you to specify the fillet radius that it uses for future fillet operations:

    Specify fillet radius <0.0000>:
  3. Type a fillet radius and press Enter.

    The number you type will be the radius of the arc that joins the two lines.

    AutoCAD then asks you to select the first object:

    Select first object or [Undo/Polyline/Radius/Trim/ Multiple]:
  4. Select the first line of the pair that you want to fillet.

    AutoCAD prompts you to select the second object for filleting:

    Select second object or shift-select to apply corner or [Radius]:
  5. Select the second line of the pair that you want to fillet.

    AutoCAD fillets the two objects, drawing an arc of the radius that you specified in Step 3. The arc isn’t connected to the two objects.

    In AutoCAD 2014, if you pick the first and last segments of an open polyline, an appropriate fillet or chamfer is then applied to close the polyline.

Fillet has more tricks up its sleeve:

  • You can fillet two lines and specify a radius of 0 to make them meet at a point. (Note that this technique produces no arc rather than a zero-radius arc.)

  • If you have lots of lines to fillet, whether with a zero radius or the same nonzero radius, use the Fillet command’s Multiple option to speed the process.

  • When you start Fillet and select two parallel lines, you see a nice 180-degree arc joining them.

  • You can add fillets to arcs and splines.

  • You can fillet between any two combinations of line, arc, circle, polyline, and spline.

  • You can fillet all vertices on a polyline at one time by choosing the Polyline option before selecting the object.

  • Hold down the Shift key before picking the second line automatically to produce a clean intersection (as though you’d set the fillet radius to 0). The CHAmfer command has the same Shift+select option.

The BLEND command joins Fillet and CHAmfer, offering another method for creating transitions between 2D drawing objects. Whereas CHAmfer creates beveled corners (that is, straight lines), and Fillet creates round corners (circular arcs), BLEND corners are spline objects. Choosing the Tangent option produced the red spline, and choosing the Smooth option produced the blue spline.

Unlike Fillet and CHAmfer, both of which would modify the source objects to make a radiused or beveled transition, BLEND leaves the source objects intact. Blends appeal to industrial designers and other purveyors of swoopy shapes. If you’re a mechanical drafter, stick with fillets and chamfers.