Centerline on an ellipse?

[lskow4]

hello everyone! new to the forums, I am a student at Island Drafting and Technical institute. As I've been tearing through my projects I've run into a bit of an issue. Is there any way/option to put a proper center mark on an ellipse without having to draw your own center lines? 

[imadHabash · Accepted solution]

Hi,

for ellipse... NO there isn't direct way. BUT if you're working through AutoCAD 2017 or later then you have this option only for Arcs,Circles and lines by using CENTERLINE and CENTERMARK commands. maybe you can use them (center marks ) to match (MA command) your ellipse center lines. >> Click <<

Regards,

[Kent1Cooper]

A workaround, admittedly, and not so very elegant, but you could draw a Circle with its center at the Ellipse's center and its radius defined by a quadrant point of the Ellipse, use DIMCENTER on the Circle, and Stretch or Scale appropriate resulting Lines.  If the Ellipse isn't orthogonally oriented, you'd also have to Rotate the resulting Lines, but a quadrant point would give you the angle easily.

But I suspect a routine could be written pretty easily to do it -- I'll think about that later....

[Muhammed.OPERA]

There's no option like this for ellipse.
Ther's many ways for you to draw this yourself.
I think the fastest way is to draw two perpendicular XLINEs in the center and define there line type as center, then offset the ellipse and use XTRIM command to trim all lines outside the offseted one, then delete the offseted ellipse, just to make the offset of the lines equal in every direction.
Good luck with that.
You can also mmake a dynamic block with these centers using many magical points like stretch point to lengthen the lines and rotate point to rotate these centerlines with certain angle, ....... .

[Kent1Cooper]

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@Kent1Cooper wrote:

.... 

But I suspect a routine could be written pretty easily to do it -- I'll think about that later....

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... which I have now done.  See the attached DimCenterWithEllipse.lsp file, which Undefines the native Dimcenter command, and makes a new definition of it that also works with Ellipses, but keeps within the same command name working with Circles and Arcs, too.  See the comments at the top of the file.