Normally CATIA does not allow user to extrude an open or self intersecting profile. It is not possible to extrude such profile unless you define a thickness of the extrusion.
Follow these steps to extrude an open and/or self intersecting sketch.
1. Create a sketch with an open and/or self intersecting profile – Fig.1.
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| Fig.1 |
2. Use this sketch to create a Pad, in the Feature Definition Error window click on Yes – Fig.2
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| Fig.2 |
3. In the Pad Definition, in Profile/Surface section check the option Thick – Fig.3. Click on More to expand the Pad Definition window.
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| Fig.3 |
4. Define thickness or thicknesses of the extrusion in the Thin Pad – Fig.4. And click on OK.
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| Fig.4 |
5. An extrusion of a self intersection and open profile has been created – Fig.5.
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