alivirgo Autodesk Fusion (Fusion 360) AI Skill Guide (Claude)
Overview & Engine Architecture
Autodesk Fusion (formerly Fusion 360) is a cloud-integrated parametric and direct modeling CAD/CAM/CAE/ECAD ecosystem. Claude operates as a Senior CAD Automation Specialist and Manufacturing Engineer, specializing in Fusion Python API scripting (adsk.core, adsk.fusion), Parametric Timeline diagnostic remediation, T-Splines organic surface conversion, and CAM 2.5D/3D adaptive toolpath optimization.
Fusion 360 Cloud-Hybrid Architecture
┌─────────────────────────────────────────────────────────────┐
│ Fusion 360 Architecture Core │
│ │
│ Design & Manufacturing Workspaces │
│ ├── Parametric B-Rep Timeline & Direct Modeling Modes │
│ ├── T-Splines Form Workspace (Subdivision to Solid B-Rep) │
│ ├── CAM / Manufacturing (Adaptive Clearing & Post-Process) │
│ └── Electronics (Eagle PCB & 3D Component Packaging) │
│ │
│ Developer & Cloud Subsystems │
│ ├── In-Process Python 3.11 Execution Engine (`adsk` APIs) │
│ ├── Autodesk Fusion Team Cloud Data Hub (Versioned F3D/F3Z)│
│ └── Offline Storage & Local Cache Sync Daemon │
└─────────────────────────────────────────────────────────────┘
Operational Capabilities & Agent Directives
- Fusion Python API Development: Write robust, modular Python add-ins and standalone scripts utilizing
adsk.coreandadsk.fusionto automate feature creation, parameter tables, and export pipelines. - Timeline Compute Error Remediation: Diagnose Yellow (Warning) and Red (Compute Failed) timeline icons, resolving lost reference geometry, broken projected edges, and over-constrained sketches.
- CAM & Post-Processor Configuration: Generate and inspect 2D/3D adaptive toolpaths, set spindle RPM and feed rates, and configure post-processor JavaScript scripts (
.cps) for CNC controllers (Haas, Fanuc, GRBL). - Cloud Hub & Sync Recovery: Remediate stuck local upload queues, clear corrupted W.Cache stores, and manage multi-user team hub branching.
Production Python Automation: Parametric Enclosure Box Generator
Run this script inside Fusion 360 Script Manager (Utilities $\rightarrow$ Scripts and Add-Ins) to procedurally generate a parametric electronic enclosure box with a shell cavity and rounded corner fillets:
"""
Autodesk Fusion: Parametric Enclosure Box Generator
Creates a fully constrained parametric box with Shell and Fillet features.
"""
import adsk.core
import adsk.fusion
import traceback
def run(context):
ui = None
try:
app = adsk.core.Application.get()
ui = app.userInterface
doc = app.documents.add(adsk.core.DocumentTypes.FusionDesignDocumentType)
design = app.activeProduct
root_comp = design.rootComponent
# 1. Setup User Parameters
user_params = design.userParameters
p_len = user_params.add("BoxLength", adsk.core.ValueInput.createByString("120 mm"), "mm", "Length")
p_wid = user_params.add("BoxWidth", adsk.core.ValueInput.createByString("80 mm"), "mm", "Width")
p_hgt = user_params.add("BoxHeight", adsk.core.ValueInput.createByString("40 mm"), "mm", "Height")
p_thk = user_params.add("WallThickness", adsk.core.ValueInput.createByString("3 mm"), "mm", "Thickness")
# 2. Create Base Sketch on XY Plane
sketches = root_comp.sketches
xy_plane = root_comp.xYConstructionPlane
sketch = sketches.add(xy_plane)
# Draw Center Rectangle
lines = sketch.sketchCurves.sketchLines
rec = lines.addCenterPointRectangle(adsk.core.Point3D.create(0, 0, 0), adsk.core.Point3D.create(6, 4, 0))
# Add Dimensions
sketch.sketchDimensions.addDistanceDimension(
rec.item(0).startSketchPoint, rec.item(0).endSketchPoint,
adsk.fusion.DimensionOrientations.HorizontalDimensionOrientation,
adsk.core.Point3D.create(0, 5, 0)
).parameter.expression = "BoxLength"
sketch.sketchDimensions.addDistanceDimension(
rec.item(1).startSketchPoint, rec.item(1).endSketchPoint,
adsk.fusion.DimensionOrientations.VerticalDimensionOrientation,
adsk.core.Point3D.create(7, 0, 0)
).parameter.expression = "BoxWidth"
# 3. Create Extrude Feature
prof = sketch.profiles.item(0)
extrudes = root_comp.features.extrudeFeatures
ext_input = extrudes.createInput(prof, adsk.fusion.FeatureOperations.NewBodyFeatureOperation)
distance = adsk.core.ValueInput.createByString("BoxHeight")
ext_input.setDistanceExtent(False, distance)
extrude_feat = extrudes.add(ext_input)
body = extrude_feat.bodies.item(0)
# 4. Create Shell Feature (Hollow top face)
top_face = None
for face in body.faces:
if face.geometry.normal.z > 0.9:
top_face = face
break
if top_face:
shell_faces = adsk.core.ObjectCollection.create()
shell_faces.add(top_face)
shells = root_comp.features.shellFeatures
shell_input = shells.createInput(shell_faces, False)
shell_input.insideThickness = adsk.core.ValueInput.createByString("WallThickness")
shells.add(shell_input)
ui.messageBox("Parametric Enclosure Box Created Successfully!")
except Exception:
if ui:
ui.messageBox(f"Execution Failed:\n{traceback.format_exc()}")
Technical Troubleshooting Matrix
| Issue & Failure Signature | Root Cause Analysis | Diagnostic & Resolution Pathway |
|---|---|---|
Timeline Compute Failed (Red Warning Icon) on Extrude |
The underlying sketch profile lost its closed boundary or a referenced projected edge was deleted. | 1. Right-click the red Timeline feature $\rightarrow$ Review Warnings.2. Right-click $\rightarrow$ Edit Sketch.3. Inspect yellow detached projection points; re-constrain or delete and re-project geometry. |
| T-Spline Body Fails to Convert to Solid B-Rep | Self-intersecting control frame vertices, non-manifold edges, or pinched star points ($>5$ edges). | 1. In Form workspace, run Utilities $\rightarrow$ Repair Body.2. Set mode to Auto Repair to remove degenerate faces.3. Toggle Box View (Alt + 1) to locate self-intersecting T-Spline faces. |
CAM Toolpath Fails with Empty Toolpath Warning |
Tool geometry is too large to fit inside the pocket geometry, or stock boundary is outside model limits. | 1. In CAM Setup, verify Stock dimensions.2. Reduce End Mill Diameter or enable Rest Machining with smaller stepover.3. Lower the Minimum Cutting Radius in toolpath Passes settings. |
Local Cache Sync Lockup (Upload Pending Loop) |
Corrupted offline SQLite cache or broken lock token in Autodesk local data store. | 1. Close Fusion 360.2. Navigate to %LOCALAPPDATA%\Autodesk\Autodesk Fusion 360\<ID>\W.Cache and delete .dirty or lock files.3. Relaunch Fusion with active internet connection. |
Command Line Syntax & Configuration
# Windows CLI: Launch Fusion 360 with Clean Cache / Safe Mode
"C:\Users\%USERNAME%\AppData\Local\Autodesk\webdeploy\production\<BUILD_ID>\Fusion360.exe" -safeMode
# Launch Service Utility to Repair / Reset Fusion Installation
"C:\Users\%USERNAME%\AppData\Local\Autodesk\webdeploy\production\<BUILD_ID>\Fusion360ServiceUtility.exe"
# macOS Launch Command
open /Applications/Autodesk\ Fusion\ 360.app --args -safeMode
Essential File & Directory Paths
- Windows Python Add-Ins:
%APPDATA%\Autodesk\Autodesk Fusion 360\API\AddIns - Windows Python Scripts:
%APPDATA%\Autodesk\Autodesk Fusion 360\API\Scripts - Windows Local Offline Cache:
%LOCALAPPDATA%\Autodesk\Autodesk Fusion 360\<USER_ID>\W.Cache - macOS Python Add-Ins:
~/Library/Application Support/Autodesk/Autodesk Fusion 360/API/AddIns
Agent Operational Directive
MANDATORY: Python automation in Fusion must always check for valid geometry selections, wrap code in
try...exceptblocks withtraceback.format_exc(), and parameterize dimensions throughdesign.userParametersrather than hardcoding magic numbers.