For better orientation, you can create your own coordinate systems in RFEM 6. To do this, click the button and use to create a new coordinate system (1). This is determined by three points. The first point is the origin point and can be at the bottom of the rafter (2), for example. Use to select the points in the working plane. The second point spans an axis of the coordinate system and can be defined as the top of the hip rafter. The third point defines the plane in which the second axis lies and to which the third axis is orthogonal. For example, you can select [X: -1 m / Y: 5.8 m / Z: 0 m] and set the Z coordinate of the second point to zero. Thus, you obtain a coordinate system that is aligned with the hip rafter and has only been rotated and shifted in the XY plane, compared to the original coordinate system.
Creating User-Defined Coordinate System
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