How do lines become "non coplanar"?

[BigDog]

How does 2 lines become "non coplanar" while drawing. An example: draw a square and then try to use the Fillet comand to round the corners and get a message that the lines are "non coplanar". It is starting to drive me up the wall. Has any one else had this problem and figured out how to fix it. I am using AutoCAD 2011 in 2D only when this problem happens. Thank you.

[ReMark]

There each have a different elevation.

 

Not sure how you are managing to do it. There could be a few explanations.

[BigDog]

I pulled the control lines off the vertical section and the horizontal section in order to draw the elevation of the glass doors. I need to have them fabricated and need drawings. When I try to connect the lines in the corners with fillet command they will not connect. I can use the trim command and it will trim the lines to make a nice corner. Then I try to make a pline out of the square and it will not join together. I can attach a sample if you need.

[BigDog]

This is a copy of the file I am working on.

Door Elevations.dwg

[CADgirl]

Make sure you have ortho on. That way your lines will for sure be coplanar. And use osnaps.

If you look at a front view of your drawing you can see that the lines are at different elevations.

[Dana W]

The most illustrative view is NE isometric. Lots of things are way off the zero Z elevation.

[djmikel]

Next time you are drawing, set OSNAPZ = 1 and ELEV = 0. OSNAPZ is not saved so you have to set it each time. Non coplanar happens often in civil when we use an existing conditions survey with lots of 3d points.

[BigDog]

I see the problem now. Thank you. I had started this file from a plan that some else draw. I was pulling my lines from there plan to get the side of the elevation. So much for trying to use a short cut. Thank you everyone.