AutoCAD Tip: FLATTEN Workflow: Preserve Annotative Objects and Scales

When you need clean 2D output from 3D-tainted geometry, FLATTEN is effective—but it can unintentionally impact annotative text, dimensions, and leaders. Use the workflow below to preserve annotation scales and object intelligence while achieving a zero-elevation drawing. For licensing, add-ons, and expert resources, check NOVEDGE.

Before you start

• Save a working copy or WBLOCK the selection into a new file to protect the original.
• Run AUDIT and OVERKILL to remove errors and duplicates that slow flattening.
• Confirm units and scales are correct (UNITS, annotation scale list) to avoid compounding issues post-flatten.

Isolate and protect annotation

• Use QSELECT to find Annotative = Yes for text, dimensions, leaders, and blocks.
• Move annotative objects to a temporary layer; lock or freeze that layer so FLATTEN doesn’t touch them.
• Keep paper space annotation in layout viewports or use CHSPACE to move critical notes to paper space before flattening model geometry.

Flatten only what needs it

• Target model geometry with non-zero Z: filter by Elevation ≠ 0 in Properties or via QSELECT.
• Run FLATTEN and choose “Remove hidden lines? = No” for plan work to prevent unintended deletions and to reduce entity conversions.
• If you are producing a projected 2D view from a 3D perspective, consider “Yes,” but verify results carefully.

Preserve blocks and data

• Avoid flattening annotative or attribute-rich blocks; edit geometry inside BEDIT if Z cleanup is required.
• Flatten xrefs in their source files, not from host drawings, to prevent overrides and broken links.
• Keep DIMASSOC = 2 for future work; post-flatten, use DIMREASSOCIATE where needed.

Validate results

• Use Properties to verify Elevation = 0 on polylines, lines, arcs, and hatches.
• Toggle ANNOALLVISIBLE to confirm annotative objects still display per scale. Never explode annotative objects—exploding removes their scale behavior.
• REGENALL and check multiple viewports for consistent text and dimension appearance.

When not to use FLATTEN

• Solids and complex 3D models: prefer FLATSHOT, VIEWBASE, or SOLPROF/SOLDRAW for true projection geometry without destroying model fidelity.
• Civil/survey data: export to AutoCAD (if applicable) and generate 2D deliverables via profile/section tools instead of brute-force flattening.

Post-process cleanup

• PURGE and -PURGE REGAPPS to keep the file lean.
• OVERKILL again if flattening created excess segments.
• Synchronize annotative scales across viewports and prune the Scale List (SCALELISTEDIT) as needed.

Pro tips

• For stubborn Z values, the “move up/down by a huge Z, then back” trick can reset elevations without altering annotation.
• Use Layer States to quickly protect and restore annotation layers during the process.
• Document a repeatable workflow in a script or custom tool palette button for team consistency.

Need the right AutoCAD licenses, add-ons, or workflow guidance? Visit NOVEDGE or explore AutoCAD options at NOVEDGE | AutoCAD to optimize your setup.

You can find all the AutoCAD products on the NOVEDGE web site at this page.