Create and modify 3D models > Modify 3D geometry > Chamfer an edge > Remove a chamfer
  
Remove a chamfer
1. Click Modeling and then, in the Engineering group, click the arrow next to Chamfer.
2. Click Delete. The Remove Chamfer dialog box opens.
3. Select the chamfer to remove. By default, other affected blends are highlighted in the viewport.
4. Click Add affected blends to select the other affected blends.
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• Click Clear active selection to deselect the selected chamfers.
• Click Preview to preview the model with chamfers removed and the original edges visible.
5. Click to complete the operation.
You should use the Chk & Fix option to check the validity of the part after you have removed chamfers. To delete multiple chamfers from a part, use ChainSelection.
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Select a chamfer in the viewport and click on the Command Mini Toolbar (CMT) to delete that chamfer.