To Modify Fillets
Fillets created with parametric sketching maintain relationships with the fillet references. If you modify the fillet radius, the reference draft lines are automatically trimmed or extended to maintain tangency.
You can modify individual fillets using the Fillet Properties dialog box. To open the Fillet Properties dialog box, do one of the following:
Select the fillet that you want to modify and double-click.
Select the fillet, right-click, and click Properties on the shortcut menu.
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The Trim style list in the Fillet Properties dialog box is not available if you create a non-parametric fillet on one or more model edges, that is, if you select references after clearing the Parametric Sketch in the Settings group. The Trim style list is available for non-parametric fillets on draft entities only.