• orange = main beam
    green = upright
    red = anchor points to upright

    The upright is anchored across the full width of the plate so that the stifness comes from the cross-section of the extrusion rather than relying on the cross-section of the plate. See how the upright goes across all of the metal plate?

    The same thing is happening with the main beam so the extrusions end up mating face to face. (with the plate acting kinda like a big washer)