Placing Dimensions Using Arc Attachment
While creating a driven dimension attached to an arc, a circular or elliptical entity, or a spherical or cylindrical surface, you can use the Arc Attachment list in the Dimension tab to measure the minimum, maximum, and center distances between the two selected references.
The Min and Max options of Arc Attachment enable you to specify the minimum and maximum distances between the tangent lines of the arcs. The Center option specifies the distance between the two centers of the arcs.
Min — Sets the dimension line at the minimum distance on the arc.
Max — Sets the dimension line at the maximum distance on the arc.
Center — Sets the dimension line at the center of the arc.
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The Arc Attachment menu is active only when you select the dimension referenced to an arc, a circular or elliptical entity, or a spherical or cylindrical surface.
In the following example, both the selected references are arcs. To measure the minimum distance between the selected entities, select the Min option for both the references from the Arc Attachment list.
When you choose the Min option for the first reference and the Max option for the second reference, the dimension changes as shown.
When you choose one of the references as an arc or a rounded surface and the other reference is a straight line or a flat surface, the Arc Attachment menu is available only for the arc reference or circular references.