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Question re meaning of self-intersecting

leslie_edmanleslie_edman OS Professional Posts: 1 PRO
Hi, One surface is defined to a sketch plane.  The same surface shape, slightly rotated, is defined to a parallel sketch plane.  Both surfaces have the same number of vertices and the two surfaces do not share a common axis of rotation.  A loft between the two, using matching vertices, does not regenerate properly due to a self-intersecting body error.  Can someone explain what is meant by this?  I do not understand how sketches on parallel planes can cause anything to self-intersect.  Thank you.  Leslie


  • NeilCookeNeilCooke Moderator, Onshape Employees Posts: 5,253
    It is self-intersecting if there is a ripple or kink in the surface so that the surface intersects itself. Please post a link to your document. 
    Senior Director, Technical Services, EMEAI
  • philip_thomasphilip_thomas Member, Moderator, Onshape Employees, Developers Posts: 1,381
    edited December 2017
    @leslie_edman - Is there a public link to the loft you are trying to create?

    Generally, if you post a link on these forums, 5 guys will fall over themselves to fix it for you - and at least one will offer a written explanation. Just asking for an essay on why lofts fail is hard to answer.

    That said . . . . imagine a rectangular bath sponge. Now bend it. All is fine until the bend is sufficient to cause the sponge to crease. At that point you would get the error 'self intersecting body' :)

    I hope this helps :)
    Philip Thomas - Onshape
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