NEW ROOTS DEVELOPMENT
Home›Tool Guide›VDC Utilities›Drawing Tools

Export plain AutoCAD (flattened)

Exports a plain-AutoCAD copy with every Civil 3D object exploded, flattens it to Z = 0 so design elevations do not leave with the file, purges it, and then re-measures the result to confirm nothing AEC or proxy survived. The original drawing is never touched. Civil 3D already owns the export ( AeccExportCivilDrawing ) and almost nobody knows it exists: this adds no export logic of its own, it adds everything around it.

Command VDCEXPORTCAD · VDC Utilities tab › Drawing Tools panel
Exports a plain-AutoCAD copy with every Civil 3D object exploded, flattens it to Z = 0 so design elevations do not leave with the file, purges it, and then re-measures the result to confirm nothing AEC or proxy survived. The original drawing is never touched. Civil 3D already owns the export (AeccExportCivilDrawing) and almost nobody knows it exists: this adds no export logic of its own, it adds everything around it.
Export → flatten → purge → VERIFY. The last step is the one the native command does not have. 1. Export (native) Civil 3D's own exporter, driven with FILEDIA=0 so it needs no dialog. Objects explode. 2. Flatten to Z = 0 On the exported COPY only, as a side database. The reason most people run this. 3. Purge The export is a disposable copy, so it purges hard. 4. VERIFY Re-measures the result and NAMES anything still off Z = 0, or any AEC / proxy survivor. Layer filtering, and the trap in it The Civil 3D export only writes what is VISIBLE, so filtering is done by hiding layers. Three modes: export everything, remove layers matching a pattern, or keep only those matching. Filter on the EXPORT's layer names, not the source drawing's. A Civil 3D object draws its components on STYLE-assigned layers, so an exploded surface or pipe network lands on those component layers, a pattern aimed at the object's own layer matches nothing. The report lists every layer in the export with a count, biggest first. Run once, read the list, write the pattern, run again. The filter is ENFORCED, not assumed. Hiding a layer before the export is only a request. The exported file is re-measured per layer afterwards and anything on an excluded layer is erased from the export, model space and block definitions alike. The report says which happened. Flattening removes elevation from GEOMETRY only. Elevations written as TEXT, spot labels, pad callouts, contour labels, still read in the export. If the point is that no elevations leave, check the text too.
Export / filter   Flatten / enforce   Verify / caveat

What it adds over the native command

  • Version, xref bind, bind type, prefix and suffix move out of -AecExportToAutoCAD's option letters and into a dialog, saved to JSON.
  • “Export Feature Line as 2D” is stored PER DRAWING, six levels into Toolspace, and needs the drawing saved. Set it once here; applied per drawing and restored afterwards.
  • Scopes: current drawing, all open drawings, or a whole folder, instead of one drawing and one Save dialog per run.
  • Refuses to write over a source drawing. CSV log per run.

How the flatten works

  • Implemented natively, not by driving Express Tools FLATTEN, same reasoning as Clean DWG's MAPCLEAN passes: deterministic, no dialog, reportable, identical every run.
  • Lines, 3D polylines and splines flatten per vertex / control point.
  • Everything else at a single elevation moves by a rigid -Z displacement, preserving text justification, hatch associativity and dynamic block state.
  • Simple 3D polylines are rebuilt as 2D polylines, a 3D polyline renders every linetype as continuous unless the recipient runs LineType3DPlineOn.
  • Block definitions are flattened too by default: the export is a disposable copy.
  • Layers are turned off, not frozen (freezing the current layer throws); the source drawing is changed in memory only, restored the instant the export finishes, and never saved.

Dialog

Export plain AutoCAD (flattened) dialog
Export plain AutoCAD (flattened), VDCEXPORTCAD
Settings file: %APPDATA%\VDC\ExportCad\settings.json

When to use it

  • An architect, contractor, or agency asks for 'a CAD file' and does not have Civil 3D.
  • You are sending linework out and the elevations should not go with it.
  • A recipient's software chokes on Civil 3D objects or shows them as proxies.

How to run it

  1. Run VDCEXPORTCAD; leave the mode on Preview for the first pass.
  2. Set the scope (Current drawing is the usual case), the output folder, and the name template.
  3. Check the DWG version and xref binding against what the recipient needs.
  4. Re-run in Apply mode and read the per-file report.
  5. Open the export before sending it - anything still off Z=0, or any AEC survivor, is called out by name.

Options

  • Mode: Preview (list what would be exported, write nothing) or Apply.
  • Scope: current drawing, all open drawings, a folder, or a folder and its subfolders.
  • Naming: template with {name} {prefix} {suffix} {ver} {date} tokens; skip / overwrite / auto-number on collision.
  • Version + xrefs: DWG format year, bind xrefs yes/no, and bind vs insert.
  • Exploded feature lines: which plain AutoCAD entity a feature line becomes - 2D or 3D polyline. Forced to 2D while Flatten is on.
  • Layers: export everything, remove layers matching a wildcard, or keep ONLY layers matching one (e.g. C-TOPO-*;*-EXIST). Anything matching is erased from the export.
  • Flatten: sets every entity in the export to Z=0, rebuilds 3D polylines as 2D, and includes block definitions.

Watch out for

  • Flattening removes elevation from GEOMETRY only - contour labels, spot elevations, and invert callouts still read as text in the export.
  • The layer filter matches the EXPORT's layer names, not the source drawing's. Civil 3D objects draw their components on style-assigned layers, so an exploded surface or pipe network lands on those component layers - not the layer the object sat on. Run once, read the layer list in the report, then write the pattern.
  • Insert-type xref binding merges xref layers into the host (XREF|C-ANNO becomes C-ANNO); Bind keeps them distinct.
  • Exploded CAD cannot be edited as Civil 3D any more - a recipient who wants to keep working in Civil 3D needs a bind-and-send instead.
  • Entities on a tilted plane are reported, not flattened - zeroing an elevation measured along a rotated normal is meaningless.
  • 3D solids and meshes cannot be flattened, so by default the ones carrying elevation are ERASED from the export - a 3D face mesh rebuilds as a surface in one click. Everything erased is listed by type and layer; the source drawing is untouched.
  • The export gets a purge, not an audit - AUDIT has no side-database equivalent. Run VDCSUPERCLEAN on the export for a full clean.

Related: Clean DWG · Super Clean · Xref QC · Plan Email