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Seeing Red Lines Shelling

minesh_govenjiminesh_govenji Member Posts: 2
This is my very first project using onShape. Please excuse any incorrect usage of industry language or terms.

I am seeing red lines on part/ shapes when I try shell out my model. 

I am trying to shell this shape:

But I see these red lines when I click on shell:

Any help with issue will be helpful. Thanks! 


  • TimRiceTimRice Member, Moderator, Onshape Employees Posts: 255
    The red lines indicate the edges that are preventing the shell feature from solving. If you can make your document public and reply with the url someone from the community may be able to take a look and help!
    Tim Rice | User Experience | Support 
    Onshape, Inc.
  • philip_thomasphilip_thomas Member, Moderator, Onshape Employees, Developers Posts: 1,381
    edited March 2019
    In the absence of a public Document to work on - does this help?


    The Variable numLobes works from 3 to n (not sure what the upper limit is).
    Philip Thomas - Onshape
  • billy2billy2 Member, OS Professional, Mentor, Developers, User Group Leader Posts: 1,410 PRO
    Phillip's geometry is really clean and therefore it'll shell. 

    @minesh_govenji your geometry, specifically this:

    You see those double edges in the center of the image?, that won't work. Shelling isn't magic and requires clean geometry.

    To figure out which faces are violating a shell, offset the faces and when offset stops working, that's your problem. Shell offsets the faces 1st. If you can't offset them, it won't be able to either.

  • philip_thomasphilip_thomas Member, Moderator, Onshape Employees, Developers Posts: 1,381
    ^^^What Bill said :)

    Philip Thomas - Onshape
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