Center Marks and Centerlines in AutoCAD

AutoCAD 2020 is here and there are still some useful routines that have been introduced in previous versions yet not fully implemented into our workflow. With AutoCAD 2017 a couple simple yet favorite commands of mine are the Centerline and Center Mark commands which you can add to existing geometry.

Type CENTERLINE or CENTERMARK at the command prompt or on the Ribbon – Annotate Tab – Centerline panel, select the Center Mark or Centerline as shown below.  By selecting the image you will be taken to the knowledge network showing an article on these commands.

These center lines and center marks will remain associated with the objects you selected when they were created. These lines are linked together, therefore changing the position of the original geometry the centerline and center mark geometry will change to reflect the updated position. The following video shows the two objects that are associated with the Centerline. Notice when I move the outer lines the centerline retains it’s position and remains in the center of the two lines regardless of whether I move and/or stretch the associated objects.

The Center Mark command will put center marks on a circle or arc. This command creates a cross-shaped mark at the center of a selected circle or arc shown in the quick video.

These Center Marks will have properties associated to each of those as shown in the window in the upper right of the image which can be found on the properties palette. Select the Center mark and hit CTRL+1 to see the properties palette and located the geometry section. You can control the distance, size, and display of the objects by using the properties palette as shown.

Let’s review from the image shown below with the numbers representing the geometry as shown on the properties palette in the upper right of the image.

1. Cross Size: this will control the size of the cross
2. Cross Gap: the gap between the cross and where the extension line begins.
3. Left Extension: Distance from the grip on the end of the circle to the end of the line.
4. Right Extension: Distance from the grip on the end of the circle to the end of the line.
5. Top Extension: Distance from the grip on the end of the circle to the end of the line.
6. Bottom Extension: Distance from the grip on the end of the circle to the end of the line.

7.  Show Extension: This determines if you just get the cross or the extension lines. You have the ability to turn on and off.  The following video shows what this switch does.

These two new commands can be very helpful when creating detail sheets for projects as well as locating and maintaining the Centerlines of objects in AutoCAD.

Prior to publishing this tip, I noticed Jaiprakash Pandey – SouceCAD had previously posted on this very topic. Please take a look at his article as well as it provides additional information on the use of these new tools in AutoCAD. Take time to visit his website as he has a very large amount of AutoCAD tips, tricks, and training materials to help you as you work in AutoCAD.

Sam