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円弧が閉じれません。arc cannot closed

Toshimichi_OdaToshimichi_Oda OS Professional Posts: 44 PRO
スケッチで円弧の自由端点を もう一方の端点までドラッグします。


I drag one free end of arc to another end in sketch.
Then the arc is invisible.
I expect it will be closed and become a circle.

And I cannot close spline :



  • 羽根_隆嘉羽根_隆嘉 Member, Channel partner Posts: 2
  • Toshimichi_OdaToshimichi_Oda OS Professional Posts: 44 PRO
    うまくいかないのは、「自由端点を もう一方の端点までドラッグ」するときです。

  • bruce_williamsbruce_williams Member, Developers Posts: 835 PRO
    edited July 2021
    @Jake_Rosenfeld or others - 

    Could you do a demo of creating closed spline as the OP is trying to do?  I have not done these and do not follow the first option of Jake's instructions.

    You can drag one of the endpoints over the other endpoint to lock them together (or just create a 'coincident' constraint between the two).  You will then have a closed spline that is probably discontinuous at that one point.  To fix this you could draw a construction line between the two handles, and then set a coincident constraint between the discontinuous point and that construction line."

    https://forum.onshape.com/discussion/9875/how-to-close-an-existing-spline#:~:text=You can drag,that construction line.

  • matthew_stacymatthew_stacy Member Posts: 357 PRO
    @Toshimichi_Oda, how many spline points do you have.  I believe that creating a "closed spline" requires three or more. If you have only two, then the sketch geometry is "degenerate".

    The attached screenshot shows the error message that popped up when I tried to delete the third spline point.

    I hope this helps.
  • Jake_RosenfeldJake_Rosenfeld Moderator, Onshape Employees, Developers Posts: 1,646

    I just retried my instructions and you are correct that they don't work...

    I think the best way to go about this is to just sketch a new spline on top of the old spline, making sure to close it up
    Jake Rosenfeld - Modeling Team
  • Toshimichi_OdaToshimichi_Oda OS Professional Posts: 44 PRO
    Jake_Rosendfeld,  Thank you for your retry.
    I remember that I was able to close spline too. But now cannnot.

    I guess that arc cannnot be closed for the same cause.


  • bruce_williamsbruce_williams Member, Developers Posts: 835 PRO
    edited July 2021

    yes, in both cases it is necessary to draw it closed. they do not allow dragging to close.  Makes sense. If you need a circle or closed spline just draw it as such.
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