Course 24: 3D ACIS Solid Direct Editing (SOLIDEDIT), Shelling & Section Plane Orthographic Extraction
Modify imported dumb 3D solids without history trees using SOLIDEDIT (Move/Offset/Taper/Delete Faces), SHELL, and generate 2D shop drawings via SECTIONPLANE and FLATSHOT.
1. Engineering Architecture & Core Methodology
When mechanical engineers import a vendor `.STEP` or `.SAT` casting into GstarCAD 2027, the resulting `3DSOLID` has no parametric feature history tree. How do you shift a bolt boss by `15 mm`, change a counterbore diameter from `Ø18` to `Ø22`, hollow out a housing to `4.0 mm` wall thickness, or delete an unwanted fillet? The answer is **Direct B-Rep Topology Editing (`SOLIDEDIT` & `PRESSPULL` / `Ctrl+Click` Sub-Object Grips)**.
2. Step-by-Step Production Workflow & Command Modules
Module 1: Direct Face Manipulation (Offset, Move, Rotate, Taper & Delete Faces)
Launch SOLIDEDIT → Face (or hold `Ctrl` while clicking a planar or cylindrical face on a `3DSOLID`). Use **Offset Faces** on a cylindrical hole face to change its diameter directly, **Move Faces** to reposition a pocket or boss along a vector while adjacent walls heal automatically, and **Delete Faces** to strip away fillets and chamfers cleanly!
Module 2: Thin-Wall Housing Shelling & Edge Imprinting (SOLIDEDIT > Body)
Run SOLIDEDIT → Body → Shell, select the 3D solid, click the open bottom/port faces to exclude from shelling, and enter the wall thickness (e.g., `3.5 mm`). Use **Check** (`SOLIDEDIT > Body > Check`) to validate ACIS topological health, and **Separate** to split disjoint solid lumps resulting from a `SUBTRACT` operation.
Module 3: Live Section Planes & 2D Shop Drawing Generation (SECTIONPLANE & FLATSHOT)
Run SECTIONPLANE to place an interactive cutting plane across a 3D assembly, toggle LIVESECTION to inspect internal O-ring grooves, and run SECTIONPLANETOBLOCK (or `FLATSHOT`) to generate associative 2D orthographic and cross-hatched section blocks ready for Paper Space dimensioning.
3. Command, Variable & Standard Reference Matrix
| Command / Parameter | Scope / Target | Engineering Behavior & Best Practice |
|---|---|---|
SOLIDEDIT > Face > Delete |
Fillet / Hole Removal | Deletes selected fillet, chamfer, or hole faces and heals adjacent B-Rep surfaces. |
SOLIDEDIT > Face > Offset |
Boss / Bore Resizing | Offsets planar or cylindrical faces inward/outward without redrawing sketches. |
SOLIDEDIT > Body > Shell |
Thin-Wall Enclosures | Hollows a solid into a uniform wall thickness while opening selected port faces. |
SECTIONPLANETOBLOCK |
2D Section Generation | Extracts cut-plane cross-sections with automated background silhouettes and hatches. |
4. Automation Script & Reference Implementation (3D Solid Audit & Sub-Object Selection Setup LISP)
(defun C:SOLIDPREP ()
(setvar "SUBOBJSELECTIONMODE" 0) ;; Allow Ctrl+Click on Faces, Edges, and Vertices
(setvar "LEGACYCTRLPICK" 0)
(setvar "CULLINGOBJ" 1) ;; Ignore hidden back-faces during 3D sub-object selection
(setvar "HISTORIES" 0)
(princ "\n[Course 24] Enabled 3D Face/Edge Ctrl+Click direct editing & back-face culling.")
(princ)
)5. Production QA Verification & Competency Checklist
- Before applying `Shell` to a complex housing, add small outer fillets last (or delete tight fillets via `Face > Delete`) so offset surfaces do not self-intersect.
- Use `SOLIDEDIT > Body > Separate` whenever a `SUBTRACT` cut splits one `3DSOLID` into two disconnected pieces that still highlight as a single object.
- Always set `LEGACYCTRLPICK = 0` so `Ctrl+Click` selects 3D solid faces and edges cleanly.
Enterprise AC1032 Database Internals & Cross-Version Diagnostics
In multi-office engineering environments operating across GstarCAD 2027, GstarCAD Mechanical, GstarCAD Architecture, and legacy AutoCAD (2018–2027) seats, mastering Course 24: 3D ACIS Solid Direct Editing (SOLIDEDIT), Shelling & Section Plane Orthographic Extraction requires understanding how the underlying AC1032 DWG binary database serializes entity handles, symbol table records, and Named Object Dictionary (NOD) pointers.
1. DWG Header & Registry Persistence Scope
Variables and object properties fall into three persistence scopes: Drawing-Saved (DXF Header) variables that travel with the .dwg file to subcontractors, Registry-Saved (Profile .arg) settings that persist per Windows workstation user, and Session-Volatile states that reset on every launch unless locked inside acaddoc.lsp. Always verify persistence scope via SYSVDLG before issuing sheets to an ISO 19650 Common Data Environment (CDE).
2. Multi-Core Regeneration & Memory Hygiene
When processing large civil corridors, dense plant P&IDs, or 50-sheet architectural Xref trees, unpurged Registered Application IDs (REGAPP), orphaned DGN stroke dictionaries, and redundant annotation scales degrade spatial index (INDEXCTL = 3) lookup speed. Executing a pre-submittal AUDIT, command-line -PURGE → Regapps, and OVERKILL pass keeps file open times under 2 seconds on GstarCAD's multi-threaded graphics kernel.
3. Hybrid AutoCAD + GstarCAD Team Coexistence
Because GstarCAD reads and writes native AC1032 binary records without intermediate import/export translation, dynamic block grips, associative hatches, XData payloads (DXF groups 1000–1071), Paper Space viewport layer overrides (VPLAYER), and X.509 digital signatures round-trip losslessly between AutoCAD and GstarCAD seats on shared SMB/BIM cloud folders.
Production Field Verification Protocol (ISO 9001 / ISO 19650 Gate)
- Baseline Template Audit: Confirm that the active drawing inherits layer naming, linetype scales (
PSLTSCALE = 1,MSLTSCALE = 1,LTSCALE = 1.0), and dimension styles from the enterprise.dwt/.dwsstandards file viaCHECKSTANDARDS. - Coordinate & Unit Integrity: Run
-DWGUNITSor checkINSUNITS,LUNITS, andMEASUREMENTto guarantee 1:1 metric (`mm`/`m`) or imperial (`in`/`ft`) block and Xref insertion scaling, withOSNAPZ = 1preventing unintended 3D elevation drift. - Submittal Packaging & Mobile Review: Lock all Paper Space viewports (`DisplayLocked = Yes`), bind or relative-path all external references via
ETRANSMIT, and verify final plotted PDF/A lineweights (`ISO full bleed`) alongside DWG FastView mobile cloud markup links.
Related Engineering Guides, Courses & Troubleshooting FAQs
Continue building your CAD engineering mastery with these related GstarCAD Academy technical references:
- [Engineering Guide] Metric-to-Imperial CAD Scaling Factors, INSUNITS & Viewport Ratios Cheat Sheet
- [Engineering Guide] Sheet Metal K-Factor, Bend Allowance (BA) & Bend Deduction (BD) Chart for CAD/CAM
- [Engineering Guide] Civil Earthwork Cut/Fill Slope Ratios, Bulking Factors & Manning's n Reference
- [Troubleshooting FAQ] How to Fix 'Drawing File Is Currently in Use / Locked' (.DWL & .DWL2) After a Crash
- [Troubleshooting FAQ] How to Fix OSNAP Snapping to Wrong Z-Elevations and Flatten Non-Coplanar 3D Lines
- [Troubleshooting FAQ] How to Fix VISRETAIN: Xref Layer Colors, Linetypes & Freeze States Resetting on Reload
- [Skill Certification] Test Your Mastery on the 850-Question GstarCAD Engineering Certification Engine →
Practice This Workflow in GstarCAD 2027 Professional
Engineered by Suzhou Gstarsoft Co., Ltd. (SSE: 688657), GstarCAD 2027 delivers 100% native AC1032 DWG compatibility, perpetual licensing, and zero-day AutoCAD parity.