Straighten Tool
The Straighten tool is used to look for holes and planar faces that are inclined at angles less than a specified value.
The examples below show how the tool straightens the faces.
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The hole is adjusted equally relative to the center. So, the top edge shifts to the Left and the bottom edge shifts to the Right.
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The face is adjusted about its center. So, the left end adjusts Upward and the right end adjusts Downward.