A post in the discussion group the other day got me thinking.  How can one use the AutoCAD scale command on points but preserve the elevations?  Short answer – you can’t…with only the scale command.   Long answer – there’s a solution – read on.

What we have here are some points (the polyline is there so you can see where the points were after we scale them.

Using the AutoCAD scale command with 2X as the factor we have this.  Notice the point elevations are twice the original.  This is as expected.

The idea now is we want the points to stay where they are, but we want the elevations to be what they were originally.

1. Create a new Point File Format with only 2 columns.  Point Number and Point Elevation.  It’s  VERY important that only these 2 columns be present in this format.
   
2. Copy your point ASCII file and remove all but the Point Number and Elevation columns using MS Excel or another spreadsheet editor.
   
3. Re-import points but select the new ASCII file from step 2.  Make sure you select the new Point File Format you made from step 1.
   
4. Civil 3D will report that points already exist with the same number…how should we resolve the conflict.  Select “Overwrite”.
   
5. Voila, the scaled points stayed scaled, but the elevations are now back to the original.
   

I hope this helps you out.  I wish I had thought of this a few years ago!

Your friendly neighbourhood Civil 3D tech,

Matt