Z values

[tcclegg]

G’ Day all
I have come across a problem in Auto CAD which I hope someone on this site will be able to help me with??
I am using AC 2004 and am working on a new project which is a big site layout so I am at times working a long way from 0,0,0. I am also working in world coordinates and using Xrefs to split up site locations. BUT when I am sometimes drawing I get Z values in the drawing and I have only been drawing in 2D .
It seems to happen when you cut and paste from different parts of the site drawing??
And offcourse when Z values start to arrive they spread like wild fire.
Does anyone have any ideas how to stop this and keep clean 2D drawings or is there a problem with AutoCAD when working in world coordinates and so far from 0,0,0?
Kind Regards
Trev

[Cad64]

I have a ritual that I go through whenever I receive a file from an outside source. I first save out a copy of their file to an xref folder and place an 'X' in front of the name so that I know it's an xref. That way, I always have their original to go back to if need be. I then go through the xref drawing and detach all xrefs and image files, (I don't like nested xrefs). I delete all layer filters, layer states, layout tabs and any excess junk around the perimeter of the project limits. I then purge, audit and flatten. This makes the file as lean and clean as possible. Only then do I insert into my drawing. Ever since I adopted this policy, I never have problems with Z values anymore.

[CarlB]

If a drawing has z values and you copy and paste using osnaps, then you will get the z value proliferation problem you describe. I don't believe distance from 0,0 has anything to do with it.

You can use the Express Tools command "flatten" to set all z values to 0 (in most cases).

[tcclegg]

I will give that a go from now on. But the system I am working on is full of Z values.
Fllatten is good but its not working very well. Thanks for your help.
I will try some things on monday and keep you posted.