W Elipse Arch settings

[Anonymous]

How do I determine what the larger circle is in an eliptical arch created from the w Elipse arch settings in the window tool?

As you can see in the atached, the W elipse gives you the "Shorter Radius" but it doesn't say what the larger radius is.

See 2nd post to see how I used to draw my eliptical arches in autocad.

In case anyone is wondering why I need this, it's because I need to show the dimensions and radius so my framer will create the arch properly.

[Anonymous]

See the attached image for how I draw this in Autocad (I am a recently converted Archicad user)

[TomWaltz]

If this is just an opening, I would probably make a custom one.

See my post from earlier today:
http://archicad-talk.graphisoft.com/viewtopic.php?p=54825#54825

[Anonymous]

Thanks, I could do that and I know how, but the W Elipse gives me the arch I am happy with, I just need that one last piece of info....the larger radius and It will save me a ton of time.

Are you saying there is no easy way to derive this radius from the W Elipse tool?

[Ignacio Azpiazu]

vincon2 wrote:
Are you saying there is no easy way to derive this radius from the W Elipse tool?

I think that the 'W Elipse' is giving you a distorted circumference (like a diagonal cut on a cylinder) and not something you can get by joining arcs of 2 radii.

On a section/elevation window you can play around with arcs and circles to produce a geometry sketch exactly like yours.

[TomWaltz]

vincon2 wrote:
Thanks, I could do that and I know how, but the W Elipse gives me the arch I am happy with, I just need that one last piece of info....the larger radius and It will save me a ton of time.

Are you saying there is no easy way to derive this radius from the W Elipse tool?

I've never figured out any real way to control it exactly.