Modifying Objects Part 1

Topics covered in this AutoCAD tutorial:

Modify tools

Modify Tools

The Modify Tools can be found on the Modify Panel on the Ribbon as well as the Modify and Modify II Toolbars. The Modify II Toolbar is hidden by default and contains the same tools that are in the Modify Panel expansion. Modify tools alter and create objects and lines based on pre-existing objects and lines. Some of the more commonly used Modify Tools will be covered in this chapter and some more tools covered in a later chapter.

All modify commands will prompt you to select objects as explained in section 1, some will also prompt you to specify a base point by clicking or entering a coordinate. The base point can be placed anywhere, but it’s usually a point on the object itself placed using an object snap. The modifications will occur relative to the base point depending on the tool.

• Move (M) : Select the objects and specify a base point. Once the base point is established, you will be prompted to specify a second point. The selected objects will maintain the same relative position to the cursor that they had to the base point, so that when you click on a second point, the objects will be moved to the same relative position to the second point. You can also snap to a tracking line and type in a distance to establish the second point. Typing in an XY value will move the objects along the objects those distances along the X and Y axes. If you enter # before you type in an XY value, the base point of the objects will be moved to that position of the XY grid.

• Copy (CO) : This tool works in a similar way to the Move tool, except instead of moving the objects relative to the base point, it will make a copy. The copy tool will allow you to place as many copies as you’d like until you press Enter to end the command.

• Rotate (RO) : With the Rotate Tool, the base point is the axis or rotation for the selected objects. You can type in an angle or rotate with your mouse and snap to Polar Tracking lines if desired. Keep in mind that any angle you enter will be counter-clockwise unless it is a negative angle. There is a Copy option in the command that will allow you to make one rotated copy. There is also a reference option that will be covered later in this chapter.

• Scale (SC) : With the Scale Tool, the base point acts as the center of scaling from which the objects scale in towards or out from. Once the base point is established, you will be prompted to enter a Scale Factor. The starting size of the object has a Scale Factor of 1, so if you enter a Scale Factor of 1, the size of the objects will not change. A Scale Factor of .5 would shrink the selected objects to half their original size. A Scale Factor of 2 would double the original size, and so on. If you select the Copy option, you will create a scaled copy of the objects. You can also scale with the mouse, but it’s not very precise, and making objects smaller is very difficult. You can scale more effectively with the mouse if you use the Reference option or activate the Scale tool through the Right–click menu of a Grip. Both methods will be explained later in this chapter.

• Mirror (MI) : The Mirror Tool will flip selected objects along a Mirror Line, so instead of a single base point, you will establish 2 points to form a Mirror Line. Typically, you will use object snap for the first point, and then choose any arbitrary point along a Polar Tracking line, since any 2 points can form a line.

• Overkill : The Overkill button can be found in the Modify Panel extension on the Home Tab of the Ribbon, but not on the Modify Toolbar. When drawing in AutoCAD it’s easy to end up with overlapping duplicate lines and objects, which can cause unexpected problems. Overkill will clear any unnecessary overlapping geometry. Simply start the command, select all the objects you suspect might be overlapping other identical objects, and press Enter.