Due to the complexity of features that you can create by lofting, a set of tests is available to ensure that the geometry will be valid for analysis. You can define loft sections and paths such that the loft feature would intersect itself. A loft feature with self-intersections would be impractical as a manufactured part and would also be difficult or impossible to mesh and analyze.

When you toggle on Perform self-intersection checks in the Feature Options dialog box, ABAQUS/CAE tests for self-intersection while it is creating the loft feature. If any faces of the loft intersect other faces, ABAQUS/CAE displays an error message stating that there are invalid intersections and does not create the loft feature. The time required to complete the tests varies with the complexity of the loft you are attempting to create. For example, if the shape of your loft varies greatly from section to section or if you have defined a complex loft path, the tests will significantly increase the time required to create the loft feature. If you choose not to include the tests, ABAQUS/CAE will create the loft feature regardless of whether the geometry is valid.