Home » How to use SolidWorks Centerlines in Drawings – a complete Guide

Centerlines are used to indicate the exact center of a component. Solidworks uses a succession of lighter long and short dashes to represent them. You need to learn how to use Solidworks centerlines in drawings. Centerlines are one of the most commonly used tools in engineering drawing. Their primary use is to depict circular or cylindrical characteristics in a drawing, which are common in mechanical parts. Bolt holes, pins, discs, and other features are common examples.

On drawings, centerlines are annotations that mark the centers of circles and describe their geometric size. You can insert centerlines into drawing views automatically or manually. The SOLIDWORKS software prevents duplicate centerlines. When you dimension to a centerline, the extension lines will automatically shorten. A sketch entity with a centerline linetype in a SolidWorks part file is always considered construction geometry.

Construction geometry is solely utilized to help create the sketch entities and geometry that are eventually incorporated into the part. When you need a new construction line to use as construction geometry, you can make it immediately because there is a distinct command for a construction line. This command is known as “Centerline.” However, when you want to create a new piece of construction geometry that is a circle (which is not as common as creating a new construction line), it is not as easy as drawing a new construction line. It is because there is no separate command for creating a construction circle as there is for creating a construction line.

Suppose you have regular lines or circles (or other sketch entities) that you want to convert to construction geometry. In that case, you can select the entity with a normal left-click (or select multiple entities by holding the Shift or Ctrl keys as you choose) and then select the icon to change to construction geometry from the shortcut menu that appears. However, with lines and circles, it is easier to draw this geometry as construction geometry straight away.

When learning how to use Solidworks centerlines in drawings, you will be able to use them to generate symmetrical sketch elements, revolved features, and construction geometry. You can have several radial or diametric dimensions without selecting the centerline every time. In a drawing, centerlines have two functions. For starters, they denote the center point or axis of a circular or cylindrical feature. Second, they assign a theoretical point in the drawing to a dimension. Another typical application for centerline is depicting a non-cylindrical portion’s symmetry. However, it would help if you attempted to avoid doing so.

How To Use Solidworks Centerlines In Drawings


Centerlines are straight lines that play a critical role in accurately interpreting engineering drawings. Knowing how to use Solidworks centerlines in drawings will help you automatically or manually create and insert centerlines into drawing views. It should be noted, however, that Solidworks software prevents duplication of centerlines.

To draw a centerline.

Step 1: On the Sketch toolbar, click centerline, or go to Tools and select Sketch Entities. Then select centerline.

Step 2: Start the centerline by clicking.

Step 3: Drag to set the end of the centerline, or move the pointer and click.

There are two methods to insert centerlines into a drawing automatically. It is important to remember that centerlines are not automatically inserted when you set large assembly settings or when the number of components in a large assembly exceeds the threshold.

Method 1

The first option for Auto Insert centerlines is “Centerlines.” To get there, go to Tools and then Options. Next, select Document Properties, Detailing, and Auto Insert on View Creation.

You will see many possibilities for auto insertion accessible to you; feel free to experiment with each of these options in your spare time to see what they each accomplish and whether or not you want to add them to your drawing templates.

The first option will add centerlines through the part regardless of view direction. As a result, this portion’s right side and isometric views show a through-hole. The image below displays a new type of centerline that can be automatically placed when a view is created.

Method 2

The second auto-insert option for centerlines is the second choice in the list, “Center marks-holes-part.” This option will add centerlines to your holes that are visible when straight on a view, as shown in the figure below. To get there, select Tools, then Options. Next, choose Document Properties, Detailing, and Auto Insert on View Creation.

To insert centerlines manually, follow the steps outlined below.

Step 1: In a drawing document, click Centerline (Annotation toolbar), or click Insert, then Annotations, then centerline. The Centerline PropertyManager will display, and you may choose whether to select a tool or an object first.

Step 2: Choose one of the following options: two edges (parallel or non-parallel); Two sketch segments in a drawing view (excluding splines); A face (cylindrical, conical, toroidal, or sweeping); A look at the graphics area A feature, component, or drawing view in the FeatureManager design tree.

Step 3: When finished, click the green tick.

The Function of Centerlines in Solidworks

  1. A centerline in a drawing denotes a circular feature. Most circular features in 2D appear identical to elements with non-circular geometry. The way to distinguish them is to create a centerline that symbolizes their central axis and confirms their geometry. Figure 2 shows a cross-section view that can assist in illustrating this; without the centerlines, the ‘holes’ would be considered rectangular rather than circular in this part.
  2. Circular features are dimensioned using centerlines as a guide. When dimensioning it, it is recommended to utilize the midpoint of a circular feature as a reference. For example, if one wanted to depict the distance between the holes or between the holes and the side edges in figure 2, one would use the centerlines rather than the hole walls.
  3. Centerlines also represent the coaxiality of features that share the same central axis. Again, this may appear insignificant, but it is essential in GD&T. A shared centerline enforces the co-axial relationship between the two features. In Figure 2, for example, all three centerlines connect two different holes. If the designer had not intended for them to be co-axial, each set of holes would have had two centerlines.

Bottom Line

I hope this article assists you in understanding how to use Solidworks centerlines in drawings.