Drawing Not staying flat

[mmiles]

I have several files that were developed over time by a person using a different version of ACAD than our office. Basically, the process was to save down to that version, work done, and then added back to the office files. The problem we have now are that non-coplanar entities keep showing up all over the place. I have flattened the file (selecting all), I have flattened individual elements, I have selected lines by Z values and changed them all to zero (0), and still many lines will revert to non-coplanar status if I modify (i.e. move) and try to fillet lines. I have to flatten, then fillet...over and over. It is getting maddening.

I have audited as well, and continually errors get found/fixed. I am running out of ideas, and my search is getting harder. Does anyone have any practical suggestions?

thanks!

[cadtag]

is the other version newer, or older?

[mmiles]

The other version is older; not sure what version, or flavor of AutoCAD.

[tedg]

...The problem we have now are that non-coplanar entities keep showing up all over the place. I have flattened the file (selecting all), I have flattened individual elements, I have selected lines by Z values and changed them all to zero (0), and still many lines will revert to non-coplanar status if I modify (i.e. move) and try to fillet lines. I have to flatten, then fillet...over and over. It is getting maddening.

I have audited as well, and continually errors get found/fixed. I am running out of ideas, and my search is getting harder. Does anyone have any practical suggestions?

thanks!

Have you checked the "elevation" of your working drawing?
Command "elevation" (or setvar "elevation")

If it's other than zero, that's what elevation you're drawing at.

..And could be snapping to endpoints of lines at a different elevation.

[cadtag]

and if the drawing you are getting in was done with a vertical app, MEP, Civil3D, architecture, the elements nested in the proxy objects may have an elevation internally that FLATTEN can't touch. e.g. the WALL object may be at z=0, but the LINEs that represent the WALL may be at a different Z.

[jaberwok]

On reading the title I thought of weights at the ends of a desk.

Sorry - not helpful, I know.

[BlackBox]

Have you checked the "elevation" of your working drawing?

Command "elevation" (or setvar "elevation")

If it's other than zero, that's what elevation you're drawing at.

..And could be snapping to endpoints of lines at a different elevation.

The OSNAPZ system variable may also be a factor; more information is needed from OP.

Cheers