The Internal Diametrical mode measures and dimensions the diameter of a circle or arc, and places the dimension inside the object.
To create a diameter dimension inside a circle or arc:
Click the Radial Dimension tool from the appropriate tool set/palette, and click Internal Diametrical mode.
● All workspaces: Dims/Notes tool set
● Spotlight and Landmark workspaces: Basic tool palette
From the Tool bar, select a Dim Std (dimension standard).
Click on or within the arc or circle to dimension.
Move the cursor to preview the dimension line location.
Click to place the dimension.
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