The break command is used for splitting objects into two or multiple objects. For example, if you want to erase the middle portion of a line, you will use the break command. The command is similar to “erase” in a graphics editing software. You can erase any portion of an object like arcs, circles or polylines. One useful thing that this command can do is you can cut a circle into half.

To proceed in our tutorial, let’s say you have a line. If you don’t have one then draw a line first. Then go to menu and select Modify>Break in the drop down menu. You can also type “break” or “br” in the command prompt. Then after invoking the command, AutoCAD will prompt: _break Select object: which means you have to select the object by placing your cursor on the object and click it. The portion you will select is the first point where the break will occur by default but you can change it by specifying “First Point” on the second prompt ( see Fig. 1). Then it will highlight and will prompt again: Specify second break point or [First Point]: . Which is telling you to point your cursor again on the second point where the break will end. But if you want to change the first point, Type “F” on the command prompt and press enter. AutoCAD wil prompt again: specify first break point: which is telling you to point your cursor on the portion of the line where you want your line break to start. After selecting, it will prompt you again: Specify second break point: then select the portion where you want to terminate the line break.

    autocad polyline icon

Fig. 1 Breaking a Line

Cutting a Circle Into Half

Erasing a portion of a circle or breaking it is a little different than an ordinary line or arc. You have to start the first point then end the break counter clockwise (See Fig. 2). If you do the opposite, it will erase the whole circle and line break will become the line. To start, it will be the same as breaking a line. This time you can type “br” on the command prompt and type “enter”. Select the first point, lets say the top of the circle.  Then select the left side portion of the circle which is counter clock wise from the first point (See Fig. 2). If you start your break at the bottom, then select the second point counter clockwise to the right.

    autocad polyline icon

Fig. 2 Breaking a Circle