円弧が閉じれません。arc cannot closed

Toshimichi_Oda

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。
円弧が見えなくなります。
円弧が閉じて、円となるべきです。

またスプラインも閉じることができません。


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 :

https://forum.onshape.com/discussion/9875/how-to-close-an-existing-spline
> HOW TO CLOSE AN EXISTING SPLINE ?

羽根_隆嘉

試しに3点円弧を2つ書き、それぞれの端点と中心点を[一致]で拘束したところ問題なく円となりました。押し出しもも問題なく出来るようです。
もしこちらの手順で出来なければ、スケッチの実際の手順を教えてもらえますか？

Toshimichi_Oda

[一致]で拘束するとちゃんと動きます。

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_williams

@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_stacy

@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_Rosenfeld

@bruce_williams

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

Toshimichi_Oda

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.

再試行ありがとう。私も以前はスプラインを閉じることはできたと思う。
同じ原因で円弧が閉じれないと私は推測します。

bruce_williams

@Toshimichi_Oda

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.