About Setting the Scale for Dimensions

About Setting the Scale for Dimensions

You can specify the size of dimensions in your drawing. How you set dimension size
depends on the method you use to lay out and plot drawings.

Dimension scale affects the size of the dimension geometry relative to the objects
in the drawing. Dimension scale affects sizes, such as text height and arrowhead size,
and offsets, such as the extension line origin offset.

You should set these sizes and offsets to values that represent their actual size
on paper. Dimension scale does not apply the overall scale factor to tolerances or measured lengths, coordinates, or

NOTE: You can use annotative scaling to control the overall scale of dimensions displayed
in layout viewports. When you create annotative dimensions, they are scaled based
on the current annotation scale setting and automatically displayed at the correct

Setting dimension scale depends on how you lay out your drawing. There are three methods
used to create dimensions in a drawing layout:

  • Dimension in model space for plotting in model space. This is the traditional method used with single-view drawings. To create dimensions
    that are scaled correctly for printing or plotting, set the DIMSCALE system variable
    to the inverse of the intended plot scale. For example, if the plot scale is 1/4,
    set DIMSCALE to 4.
  • Dimension in model space for printing or plotting in paper space. This was the preferred method for complex, multiple-view drawings prior to the 2002
    products. Use this method when the dimensions in a drawing need to be referenced by
    other drawings (xrefs) or when creating isometric dimensions in 3D isometric views.
    To prevent the dimensions in one layout viewport from being displayed in other layout
    viewports, create a dimensioning layer for each layout viewport that is frozen in
    all other layout viewports. To create dimensions that are scaled automatically for
    display in a paper space layout, set the DIMSCALE system variable to 0.
  • Dimension in layouts. This is the simplest dimensioning method. Dimensions are created in paper space
    by selecting model space objects or by specifying object snap locations on model space
    objects. By default, associativity between paper space dimensions and model space
    objects is maintained. No additional scaling is required for dimensions created in
    a paper space layout: DIMLFAC and DIMSCALE do not need to be changed from their default
    value of 1.0000.
NOTE:When you dimension model space objects in paper space using associative dimensions,
dimension values for the display scale of each viewport are automatically adjusted.
This adjustment is combined with the current setting for DIMLFAC and is reported by
the LIST command as a dimension style override. For nonassociative dimensions, you
must set DIMLFAC manually.

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