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Hi....I am trying to create a rib feature but unable to get one in given part

Best Answers

  • brian_bradybrian_brady Member, Developers Posts: 505 EDU
    Answer ✓
    The hand drawing makes you think this is possible, but it is not, regardless of the CAD system. The rib would either have to overhang due to the curve, resulting in no end surface. Make a symmetric extrude with a triangle sketch and see how the "rib" overhangs. If you make the rib sketch end before the apex of the curve by enough the rib will work.
  • MichaelPascoeMichaelPascoe Member Posts: 1,001 PRO
    edited November 22 Answer ✓

    @brian_brady is right.

    However, because the drawing didn't call out the curvature of that ribbed face, we can do anything we want. Like loft the ends of the rib and resurface the top of it:




  • S1monS1mon Member Posts: 1,062 PRO
    Answer ✓
    You could achieve what's in the drawing with a loft or some sort of surfacing. The tip of the rib can't be a flat plane and share an edge with the cylindrical surface. The tip of the rib will need to go from a slight crown to a flat.
  • brian_bradybrian_brady Member, Developers Posts: 505 EDU
    Answer ✓
    It's Schrödinger's rib; both flat and curved.

Answers

  • brian_bradybrian_brady Member, Developers Posts: 505 EDU
    Answer ✓
    The hand drawing makes you think this is possible, but it is not, regardless of the CAD system. The rib would either have to overhang due to the curve, resulting in no end surface. Make a symmetric extrude with a triangle sketch and see how the "rib" overhangs. If you make the rib sketch end before the apex of the curve by enough the rib will work.
  • MichaelPascoeMichaelPascoe Member Posts: 1,001 PRO
    edited November 22 Answer ✓

    @brian_brady is right.

    However, because the drawing didn't call out the curvature of that ribbed face, we can do anything we want. Like loft the ends of the rib and resurface the top of it:




  • S1monS1mon Member Posts: 1,062 PRO
    Answer ✓
    You could achieve what's in the drawing with a loft or some sort of surfacing. The tip of the rib can't be a flat plane and share an edge with the cylindrical surface. The tip of the rib will need to go from a slight crown to a flat.
  • brian_bradybrian_brady Member, Developers Posts: 505 EDU
    Answer ✓
    It's Schrödinger's rib; both flat and curved.
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