Converting Linear Dimensions to Ordinate
To modify a dimension type from linear to ordinate, you must first establish a reference baseline. For any set of related dimensions (dimensions that share a common plane or edge), you need to create only one baseline reference. If you just created a baseline, it remains set until you set another. Only one baseline reference can be current (set) at one time. You can select dimensions that have witness lines coincident with the set baseline and convert them from linear to ordinate dimension type.
When converting the dimension, you can also add a jog to the witness line to improve the spacing of the dimensions.
When you convert an ordinate dimension to linear, the dimension loses its association with the baseline reference. If you convert the dimension back to an ordinate dimension, you can select any appropriate baseline reference.
1. Select any ordinate dimension to convert.
2. Right-click and select Toggle Ordinate/Linear on the shortcut menu.
3. Select the witness line to be the baseline reference. The dimension changes automatically to an ordinate type dimension, indicated with a value of .00.
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You cannot select dimensions that do not share the same baseline reference.
When you switch dimensions from linear to ordinate, the baseline reference regenerates. However, if an orphan baseline (one that does not have dimensions associated with it) has driven children (dimensions), the baseline and the children do not regenerate. If many driven dimensions in a drawing reference an orphan baseline, modify the dimensioning scheme by selecting a side from which to attach the baseline. The baseline then regenerates at the correct location. To update children, choose Review > Update Draft.
Baseline references appear on the drawing or in the model as ".00". Select the baseline references, right-click, and select Erase on the shortcut menu to erase them from the drawing for cosmetic reasons. Also, you can select and delete baseline references that are no longer necessary.
The dimension to be converted to ordinate must be shown as linear. The following dimensions cannot be converted to ordinate:
A diameter dimension shown as linear
A centerline dimension