About Perimeter Dimensions
A perimeter dimension is used to dimension the total length of a chain or loop of entities. You must select a dimension that the system can adjust to obtain the desired perimeter. This dimension is called the varying dimension. When you modify the perimeter dimension, the system modifies the varying dimension accordingly. You cannot modify varying dimensions, because they are driven dimensions. If you delete the varying dimension, the system deletes the perimeter dimension.
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You cannot create perimeter dimensions for parallel blends and variable section sweeps.
The perimeter dimension tool does not work in Continue mode.
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