Sketch Bug - 3 point arc

[alan.jonesXHXUF]

Found a bug with a 3 point arc. As per attached file. Basically I run an arc between two projected points, the 3rd middle point randomly placed in space because I will drive it with a dimension. When a radius is entered the drawing is locked as fully constrained - but this is incorrect since the centre point of the radius has not been defined. (Sketch 2 in the attached file). Also visible in this little video I made to quickly show someone how to pattern on a path for fake rivets over a curved tank: https://www.youtube.com/watch?v=VAHxKFXoORE

[davebYYPCU]

Sorry to say, that sketch is not bugged in this case, as you show in the video, you had to delete the dimension, to fix the centre to your desired position.  (Not what you wanted is not a bug)

All black, and nothing can be moved, red lock on the browser label. 

Might help.....

[TheCADWhisperer]

Everything looks logical to me.

[jeff_strater]

to illustrate what @davebYYPCU , take a look at the screencast below.  If you toggle the radius dimension to driven, you can see that positioning the center will change the arc diameter.

[edit] - the screencast did not post, here is the link to it:  https://knowledge.autodesk.com/community/screencast/b6e64c5b-1597-4f0d-9664-1aa7533aa9c6 

[TheCADWhisperer]

There are two possible solutions with the same radius.

[davebYYPCU]

Logic?

Sketch 2 is not required. 

[alan.jonesXHXUF]

Adding a dimension to it shouldn't lock it in position as the centre point wasn't defined.  It did lock, so as far as I'm concerned it's a bug. As the Cad Whisperer says, there is not just one valid centre point for that radius, or sketch one wouldn't be correct would it! 

[TheCADWhisperer]

When you added the dimension - Fusion solved for the closest logical solution, found it and applied it.

Predictable behavior.  I like it!

[davebYYPCU]

Protest all you like, it’s user error.

Centre point arc, does not need the dimension.

Might help...

[pblase]

I've had the same problem, and it's not user-error. Occasionally, the three-point-arc will set the center point immediately on its own, before I've had a chance to click the mouse. There's no way to unselect it either, you just have to start all over again. Usually, it's so bad that I have to close the sketch and re-open it.

[davebYYPCU]

and it's not user-error,

How come?

[pblase]

Because the center point is selected as soon as you select "three point arc" on the menu.

[davebYYPCU]

What centre point?

[TheCADWhisperer]

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@pblase wrote:

I've had the same problem...

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No file Attached?

[g-andresen]

Hi,

that's the process.

If it should be different for you, show it in a screencast or GIF.

günther