About Joining Segments
Use the Join tool to connect two intersecting board segments. You can trim the nonintersecting portions of the segments, add a bend and bend relief at the intersection, as well as flip the orientation of the intersecting segments. Keep in mind the following points when joining segments:
The intersecting segments must be planar.
The driving and offset sides of the segments to join are swapped automatically, if necessary, to match the sides of the earliest segments created.
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Swapping the driving and offset sides can change the location of cuts located on the segments. For example, when you reorder a Join feature in the Model Tree and reinsert it before a cut that references an automatically swapped side, the location and the geometry of the removed material may change.