Available in: Sketch

Sketch an arc by defining the two end points and then the radius point.

Shortcut: a

  1. Click Sketch 3 point arc tool icon to set start point.
  2. Click Sketch 3 point arc tool icon to set second point.
  3. Click Sketch 3 point arc tool icon to set radius (or click and drag to set start point, release to set second point and click to set radius).
  4. Optionally, immediately after the arc is created, input a numerical value (or type "=#" to input a variable) for the radius and press enter. This dimensions the arc without having to use the dimension tool.

To input a variable in any dimension field after the geometry is already sketched, the equal sign (=) is not required. Type "#" to input a variable.

  • To create a semicircle, click to create the arc endpoints, then move the cursor until the endpoints and midpoint snap into a straight line and the automatic inferencing appears. Click to finish creating the semicircle.

    semicircle snaps to midpoint inference

See the Learning center course Introduction to Sketching (Onshape account required) for more information.