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The build direction is the gloval global z-direction by default. If you want to use another direction should be used, you the part have to rotate the part be rotated accordingly. The only exception to this are symmetrical Optimisationsoptimisations, for them the build direction is the positive z-direction of the symmetry coordinate system.
Attention: The Material Coordinate System does not have an impact on the build direction for the Support Reduction! The build direciton entry in the scenario refers only to the Material Coordinate System and has no impact on the Support Reduction!
General Explanation
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