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Calculate All Angles - Automatically calculates placement angles for all parts.
Reset All - Resets all placement angles to their original settings (select Yes to reset all angles when the prompt displays).
Offset Overlays - Slightly offsets the machine package overlays in the X and Y direction in the event they are obscuring the underlying CAD footprint. (If you change your mind, select the button again to undo the offset).
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To check and validate machine placement angles on a part-by-part basis, select a part under Part Number in the Machine Angle Correction Center.
Step through each part number in the Part Number list (use the Previous and Next buttons) and confirm the rotations or adjust the angles and then confirm the angles.
Make any necessary changes, then select the Confirm
button for each part number.Use these buttons to help you confirm machine placement angle settings for a selected part in the Part Number list:
Note
The Apply angle change to affected features 
button (next to the Machine Angle field) references the Features Affected drop-down. When you change a machine placement angle for a selected part, you can use the drop-down to apply the angle change for all features (Select All check box) of the part or just those features whose check boxes are selected.
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