Creating Views > Render Mode > To Set the Thickness and Visibility Options of Edge Lines
  
To Set the Thickness and Visibility Options of Edge Lines
1. From the File menu, click Options. The Creo Illustrate Options dialog box opens.
2. Next to Showing, select Illustration or Current Figure.
3. On the left, click Model. The Model-Main options page opens.
4. Under Line Styles, select Display thick/thin lines to display the outer edges with thick lines and inner edges with thin lines.
5. To show hidden lines as dashed lines, select Display hidden lines as dashed lines.
6. Define the Thick line and the Thin line for model lines.
7. Under Phantom, set the opacity for phantom lines, and then select pens for the Phantom thick and Phantom thin lines.
8. Under Render Mode, to set the Thin line tolerance type or select a whole-number angle value between 0 and 89 degrees, decreasing the angle value will show more thin lines; increasing it to show fewer.
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Setting the angle to 90 degrees will use all face borders as outlines.
9. Select the Create surface borders check box to show thin lines on all inner edges. Clear this check box to only draw thin lines on edges that are below the Thin line tolerance.
10. Click Apply to apply the options and keep the Creo Illustrate Options dialog box open, or click OK to apply the options and close the dialog box.