Create drawings from models (Creo Elements/Direct Annotation) > Modify drawings > Modify sheets > Change the default sheet scale
  
Change the default sheet scale
You can change the default scale factor on existing sheets. All subsequently created views are scaled according to the specified factor. Note that existing views are not affected by a change in the scale factor.
To change the default sheet scale,
1. Click Annotation and then, in the Setup group, click the arrow next to Properties.
2. Click Sheet.
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Alternatively, select the sheet in the Drawing Browser, right-click, and select Sheet Properties from the context menu.
The Sheet Properties dialog box opens.
3. In the Scale box, type or select the new scale factor for the sheet.
4. If necessary, specify a different sheet to be renumbered in one of the following ways:
In the Sheet box, select the sheet.
Select the sheet from the Drawing Browser, right-click, and select Apply Selection from the context menu.
5. Click Close to complete the operation.