Dimensioning Drawing Elements - SmartSketch - Help

SmartSketch Help


Dimensions supply information about the size, location, and orientation of elements, such as the length of a line, the distance between points, or the angle of a line. Dimensions are associated with the elements they refer to, so you can make design changes easily.

You can use the commands on the Label or Dimension toolbar, depending on the application that you are using, to place the following types of dimensions:


Linear dimensions


Angular dimensions


Diameter dimensions


Radial dimensions


Dimension groups

Dimension commands on the Label or Dimension toolbar have a ribbon that sets options for placing the dimension. When you select a dimension in the drawing, the same ribbon options appear. You can use the options to change the selected dimension.

Placing Dimensions

To dimension elements, you can use a dimension command on the Label or Dimension toolbar, such as SmartDimension, and then select the elements you want to dimension.

As you place dimensions, the software shows a temporary, dynamic display of the dimension you are placing. This temporary display shows what the new dimension will look like if you click at the current pointer position. The dimension orientation changes depending on where you move the pointer.

For example, when you click Distance Between on the Label or Dimension toolbar and select an origin element and an element to measure to, the dimension dynamically adjusts its orientation depending on where you position your pointer.

Because you can dynamically control the orientation of a dimension during placement, you can place dimensions quickly and efficiently without having to use several commands. Each of the dimension commands uses placement dynamics that allow you to control how the dimension will look before you place it.

Placing Dimensions with the Dimension Axis

The Axis command on the Label or Dimension toolbar sets the orientation of the dimension axis on the drawing sheet. You can use the new dimension axis, rather than the default axis of the drawing sheet, while you are using Distance Between or Coordinate Dimension. You must set Explicit on the Dimension ribbon to place dimensions that are perpendicular or parallel to new dimension axis.

Dimensioning While You Draw

To dimension elements as you draw them, you can set Dimension Keyin Values Automatically with Options on the Tools menu. Although placing dimensions as you draw is convenient, it might be necessary to delete unneeded dimensions when you have finished your design.

Using Dimensions to Drive Elements

You can place a dimension that controls the size or location of the element to which it refers. This type of dimension is known as a driving dimension. If you use the ribbon to change the dimensional value of a driving dimension, the element updates.

Dimensions that are not driving dimensions are called driven dimensions. The value of a driven dimension is controlled by the element it refers to. If the element changes, the dimensional value updates.

Because both driving and driven dimensions are associative to the element they refer to, you can change the design more easily without having to delete and re-apply elements or dimensions when you update the design.

If you want to create a driving dimension, you must first set Maintain Relationships on the Tools menu. When you are placing dimensions, an option on the ribbon allows you to specify whether a dimension is driving or driven. A driving dimension and a driven dimension are distinguished by color. There are different colors for driving dimensions and driven dimensions in a dimension style.

Not-to-Scale Dimensions

You can override the value of a driven dimension by editing its dimensional value. This makes the dimension not-to-scale. For example, if you override the dimensional value that is 15 millimeters to be 30 millimeters, the actual size of the line that you see would still be 15 millimeters.

Formatting Dimensions

If you want two or more dimensions to look the same, you can select the dimensions and apply a style with the ribbon. If you want to format dimensions so that they look unique, you can select a dimension and edit its formats on the ribbon or with Properties on the Edit menu.

Using Expressions in Dimensions

There are many instances when the dimensions of individual features in a design are related. For example, the bend radius used to manufacture a sheet metal part is usually a function of the stock thickness. You can define and automate these types of design relationships with expressions. You can select a dimension and then use the Variables command on the Tools menu to enter a formula. When the formula is solved, the dimensional value changes to the value that the formula calculates.

You might want to use dimensions with expressions for the following purposes:

  • Drive a dimension by another dimension; Dimension A = Dimension B

  • Drive a dimension by a formula; Dimension A = p * 3.5

  • Drive a dimension by a formula and another dimension; Dimension A = p * Dimension B

Setting or Modifying Units of Measure

To set the units of measure for a dimension, you can use Properties on the Edit menu. To set the units of measure for a document, you can click Properties on the File menu and then click the Units tab.

See Also

Dimension Groups
Place a Dimension Between Two Elements or Key Points
Format a Dimension or Annotation
Place a Driving Dimension