Create Fillets

A fillet connects two objects with an arc that is tangent to the objects and has a specified radius.

An inside corner is called a fillet and an outside corner is called a round; you can create both using the FILLET command.

You can fillet

  • Arcs
  • Circles
  • Ellipses and elliptical arcs
  • Lines
  • Polylines
  • Rays
  • Splines
  • Xlines
  • 3D solids

FILLET can be used to round all corners on a polyline using a single command. Also, you can use the Multiple option to fillet more than one set of objects without leaving the command.

NoteFilleting a hatch boundary that was defined from line segments removes hatch associativity. If the hatch boundary was defined from a polyline, associativity is maintained.

If both objects being filleted are on the same layer, the fillet arc is created on that layer. Otherwise, the fillet arc is created on the current layer. The layer affects object properties including color and linetype.

Instead of an arc, you can use BLEND to create a spline that connects two lines or curves, and is tangent to them.

Set the Fillet Radius

The fillet radius is the radius of the arc that connects filleted objects. Changing the fillet radius affects subsequent fillets. If you set the fillet radius to 0, filleted objects are trimmed or extended until they intersect, but no arc is created.

You can press and hold Shift while selecting the objects to override the current fillet radius with a value of 0.

Trim and Extend Filleted Objects

You can use the Trim option to specify whether the selected objects are trimmed or extended to the endpoints of the resulting arc or left unchanged.

Control the Location of the Fillet

Depending on the locations you specify, more than one possible fillet can exist between the selected objects. Compare the selection locations and resulting fillets in the illustrations.

Fillet Line and Polyline Combinations

To fillet lines with polylines, each line or its extension must intersect one of the polyline line segments. If the Trim option is on, the filleted objects and the fillet arc join to form a single new polyline.

Fillet an Entire Polyline

You can fillet an entire polyline or remove fillets from an entire polyline.

If you set a nonzero fillet radius, FILLET inserts fillet arcs at the vertex of each polyline segment that is long enough to accommodate the fillet radius.

If two linear segments in a polyline are separated by an arc segment between them, FILLET removes the arc segment and replaces it with a new arc segment of the current fillet radius.

If you set the fillet radius to 0, no fillet arcs are inserted. If two linear polyline segments are separated by one arc segment, FILLET removes that arc and extends the linear segments until they intersect.

Fillet Parallel Lines

You can fillet parallel lines, xlines, and rays. The current fillet radius temporarily adjusts to create an arc that is tangent to both objects and located in the plane common to both objects.

The first selected object must be a line or a ray, but the second object can be a line, an xline, or a ray. The fillet arc connects as shown in the illustration.

Procedures
To set the fillet radius
  1. Click Home tabModify panelFillet. At the Command prompt, enter fillet.
  2. Enter r (Radius).
  3. Enter the fillet radius
  4. Select the objects to fillet.
To fillet two line segments
  1. Click Home tabModify panelFillet. At the Command prompt, enter fillet.
  2. Select the first line.
  3. Select the second line.
To fillet without trimming
  1. Click Home tabModify panelFillet. At the Command prompt, enter fillet.
  2. If necessary, enter t (Trim). Enter n (No Trim).
  3. Select the objects to fillet.
To fillet an entire polyline
  1. Click Home tabModify panelFillet. At the Command prompt, enter fillet.
  2. Enter p (Polyline).
  3. Select the polyline.
To fillet multiple sets of objects
  1. Click Home tabModify panelFillet. At the Command prompt, enter fillet.
  2. Enter m (Multiple).

    The main prompt is displayed.

  3. Select the first line, or enter an option and complete the prompts for that option. Select the first line.
  4. Select the second line.

    The main prompt is displayed again.

  5. Select the first line for the next fillet, or press Enter or Esc to end the command.
Commands
FILLET

Rounds and fillets the edges of objects.

FILLETEDGE

Rounds and fillets the edges of solid objects.

System Variables
FILLETRAD

Stores the current fillet radius for 2D objects.

TRIMMODE

Controls whether selected edges for chamfers and fillets are trimmed.