About Rounding Sharp Edges
Use the Edge Bend tool to round sharp edges of a sheet metal part in preparation for the manufacturing process. You can create one or more sets of edge bends. You can define bend settings during feature creation, or you can predefine them using the Parameters dialog box or in the Bends area of the Sheetmetal Preferences dialog box.
You can also round sharp edges when creating revolved, extruded, blend, rotational blend, attached flat, and attached flange walls, and when creating conversion features.
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Alternatively, set the smt_add_bends_on_sharp_edges configuration option to automatically add bends to geometry with sharp edges when using wall creation tools.
Walls with sharp edges
Walls with rounded edges