You can either accept the default drawing scale value or select entities and dimensions on the drawing so that a drawing scale value is automatically calculated based on the selected entities and dimensions.

When you select a dimension on the drawing, other dimension entities attached to this dimension entity, of type linear, radius, or diameter, are automatically selected as reference entities. The drawing scale value is automatically calculated based on the dimension entity that you select, the reference entities attached, and the distance measured.

If dimension entities are not attached to the selected dimension, you must select entities on the drawing to represent the dimension entities that are attached to the selected dimension. These dimension entities are used as references for measuring distance as part of the drawing scale calculation. The distances measured are for the dimensions linear, radius, and diameter.

The drawing scale value that you specify is applied to the orthographic and auxiliary views. If you modify the selected reference dimension entities, the drawing scale value also changes automatically. The changed scale value is propagated to all the views.

Use the Calculate Scale dialog box that opens when you click Compute on the View Setup dialog box, to select reference dimension entities, calculate drawing scale value, and update the Drawing Scale box in the View Setup dialog box with the calculated drawing scale value.