unintentional Z Values

Have You Experienced Unintentional Z Values ?

AutoCAD has been 3 Dimensional for decades. Most AutoCAD Users use it for 2D Drafting (and Annotating).  Yesterday I started my roadshow at our Design Sub-Contractors. I paid a visit to a Structural Engineering Design, and met the people working at our project. I introduced myself and told a few items of my Big-Picture Plan: among other things – a set of disciplinary tool palettes, a revised template and a new profile…

Right after, I was “attacked” with a series of questions and issues. Some of those were about the project and other, focused directly on AutoCAD knowledge in general (like merge a non-standard layer to a standard one, attaching the current file to a standard *.dws file, etc.) and Elevation or Unintentional Z Values in particular.

Avoiding the Unintentional Z Values

Actually this can be solved in 2 or 3 different ways:

Z value current elevation
Opt for the Options? Replace Z value with current elevation










Unintentional Z ValuesThen, you can type at the Command Line OSNAPZ and Enter The Value of 1 instead of 0.
If you are using 2016/17/18 You Can Include the OSNAPZ (which is a System Variable) Using 1 as your preference and then You’ll get a Notification Balloon Telling that some SYSVARS have changed in your SysVarMonitor.

Repairing the problem of Unintentional Z Values

AutoCAD’s Express Tools have a FLATTEN command but I’d prefer to explain the Workaround of only using the Properties:

1st You are going to Select It All
Then, using the Properties Palette – In which you’ll see Multiple [Selection] at the Object Type – Open the Arrow to the right and filter your Selection by Object Type

For Instance, Circle (235) – the number between parentheses is the number of circles selected

to the Center Z Property and if it Varies, enter a 0′ at this field.

Here is a short list by object types:
LINE – Start Z & End Z
ARC &/or Circles – Center Z
POLYLINE – Elevation
TEXT – Z Position
You get the Idea, don’t You?

Unintentional Z Values – Conclusions:

  1. Always prefer Polylines over Lines & Arcs (Easier & Faster to Flatten).
  2. Maintain Your OSNAPZ Value as 1 (on) at all times & especially when using XREF Attachments for snapping to Points You don’t actually know…Try to look at your drawing using the Cube in a 3D View and try to draw an object Replacing the Z Value with Elevation (Which is Your Current UCS) See how it works, filtering the Z Values.
  3. Get familiar with the SysVarMonitor to correct System Variables such as OSNAPZ which might change for many reasons. SysVarMonitor is available since 2016.
  4. If You have an AutoCAD Profile of your own (or several)
  5. Every Now & Then, use the Cube and try to verify – visually – that Your 2D is flat.
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