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For objects that have no assembly axis defined, you can define the axis during the assembly process. This example uses a polygonal prism and a box.
1. Activate Assemble By Axis, and select Use Any Line from the local menu or Inspector Bar.
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2. Select the object you want to move. Then click a line or edge you want to use as the assembly axis. Be sure to click near the endpoint of the axis which will meet the other axis.
3. Click an edge or line as the destination axis. Select it near the endpoint that will meet the other axis. A preview of the moved object appears. You can move it in either direction along the axis.
4. Use the mouse or enter the move distance. If you want to rotate the object, you can enter an Angle. If the moved object is oriented backward, select Turn Over from the local menu or Inspector Bar.
5. To rotate it with the mouse, select Rotate. If you turned or rotated the object, the preview will update.
6. When the distance and angle are defined, the object moves so that the two axes are aligned.
Distance by faces, Angle by faces and Angle by axes
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