Circle segments disappear when extended

[Noah_Katz]

Very often I've extended circle segments, and at the last segment where it will finally make it to the point I want, the entire circle disappears, including different segments than the one I'm extending; see screencast.

Design: http://a360.co/2f2xMpD

[Anonymous]

The Geometry of the segment you are trying to extend is different from the outer line that you are trying to extend the circle into. 

I suppose the outer dotted line is the Belt of your Belt Grinder Design? So what's happening is that the Belt cuts through the wheel (or circle in this case) because the angles of the Belt are wrong.

[Noah_Katz]

@Anonymous

> The Geometry of the segment you are trying to extend is different from the outer line that you are trying to extend the circle into. 

It may look that way, but all of the circular segments are from dividing the same circle, and have the same radius and center.

The division is so I can measure the length between  the tangent points to the belt.

As I move components around, I need to trim and extend to follow the movement of the tangent points.

[SaeedHamza]

Hi,

I don't know if this is the case but worth the try ...

Try deleting the dimension with the curve as one of it's ends ( dashed curve ) in the red circle, because after you extended the circle, the arc was removed, and so, the dimension lost one of it's ends

Might help fixing the issue

Regards

Saeed

[Noah_Katz]

@SaeedHamza

> ...because after you extended the circle, the arc was removed

? yes, that's the problem - why did it disappear?

I don't believe it's anything particular to nearby geometry or dimensions, because it's happened many other times with other circles in the sketch.

[Anonymous]

The video got kinda long but i hope it shows what i meant earlier.

[Noah_Katz]

@Anonymous

Thanks for taking the time, but I'm really not sure what you're trying to show.

Perhaps I should have mentioned that the straight non-tangent segment and other nearby geometry isn't part of the belt or wheel; it's used to calculate the tension in the belt from force applied to the tension wheel.

[Anonymous]

What i was trying to show is that the Circle Segments don't just randomly disappear.

There must be some kind of conflict between the existing construction line (or arc) and the Circle that you are trying to extend.

I thought it was because of the geometry, which seems not to be case as we know now.

Very odd problem though. 

Sorry i couldn't help you. 

[Noah_Katz]

Must be a sketcher bug, as sometimes it works as expected.

Thanks for trying.