Fillet Curve - weird problem

I am trying to fillet two curves with a zero radius.
Fillet without JOIN fails.
Fillet with join alters the angle of one of the lines.

I can extend the curves - but cannot fillet it without joining - but joining alters the existing angle of the curve. The curves are on the same plane (z=0) and are a result from the Make2d Command.

Please see the attached screenshots.

I appreciate any suggestions. It is really frustrating to extend the lines instead of making them meet at a point based on their trajectories with the fillet command.

Why is this happening?

Rhino 6

Hello - it’s impossible to help without a file with the curves.


Hi Pascal,
Here is the file.
Thank you.Fillet Curve - weird problem.3dm (1.9 MB)

Hello - the ends of the curves are ~.003 apart, the file tolerance is .01, so I think you’re ok - just zoom out a little and you won’t notice. =)
But, really, if that matters you should model at .001 or even .0001 tolerance.


Perfect. That worked. I generally do not have to set tolerances - but in this case, the file is getting exported to Adobe Illustrator and there are issues with LivePaint because of the fillet not closing the distance between the two lines.
I changed the tolerance and it now works.
Thank you for the accurate, prompt response. I really appreciate it.