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The build direction is the z-direction of the Principal Coordinate System. For each scenario under the Build Direction the build direction can be easily rotated . Then the build direction and is then used for the Design Rules as well the as material properties are rotated accordingly.
The only exception to this are symmetrical optimisations. The In this case, the build direction shouldn’t be normal to a symmetry plane and has to be considered during the model setup.
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General Explanation
For different applications there are different priorities and for some the manufacturability is specially high. Therefore, it would be nice to push designs in a direction where the manufacturing gets easier without costing to much performance regarding the efficient design and material allocation.
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