About Normal Dimensions
Use the Normal Dimension tool to create the following types of dimension:
Linear
Radial
Diameter
Angular
Total included angle
Arc Length
Conic
Ordinate
When you create normal dimensions, you can either select the geometry and then choose the tool from the shortcut menu, or you can open the dimension tool, and then select the geometry. When you select the geometry first, only applicable dimension types are available in the shortcut menu. For example, if you select a single line, the available dimension type on the shortcut menu is length. If you select two parallel lines, the available dimension type is distance.
In sketched circles or revolved sections, you can switch between linear, radial, and diameter dimensions. For centerlines and non-parallel sketched linear entities, you can toggle between angular and total included angle dimensions.
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You can create a linear dimension between two arcs, parallel to a linear reference, at any orientation. If the linear reference is deleted, the dimension becomes horizontal. If a horizontal dimension is impossible, the dimension becomes vertical.