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Select a plane that represents where the part will split in the mold.

Find Draft in the Features toolbar, usually under Insert > Features > Draft . View File

Use options like "along tangent" to automatically select connected faces. To provide a more specific guide, could you tell me: Select a plane that represents where the part

Which software are you using (e.g., SolidWorks, Inventor, Fusion 360)? View File

Specify the draft angle and select a neutral plane or surface to define the "pull" direction. Select Faces: Select the specific faces to be drafted.