DFMCNC-002 · DFM · 3-Axis CNC · difficulty 4/5

3-ax-machinable manifold block

sha256:ab02f10c8e51dd23…

§1Prompt verbatim

Solid 80 × 60 × 40 mm aluminium block. Three Ø 6 H7 bores from the top, two Ø 4 H7 bores from each side, all intersecting an internal Ø 8 manifold channel running along the long axis. The geometry must be fully machinable on a 3-axis VMC with Ø 6 → Ø 4 → Ø 1 tools, plus a 90° drill-rotation between sides.

§2Ground-truth spec

shells1

watertighttrue

manifoldtrue

acceptance ε±0.05 mm

featuresmanifold_channel, bore_H7_x7

§3Reference render

canonical reference · drag to orbit, scroll to zoom

Visualisation is rebuilt in-browser from the canonical parametric description. Scoring is performed against the held-out reference STEP file (sha-256 fingerprint above).

§4Per-agent renders

reference + 10 agent outputs · scored against the held-out STEP

vol IoU · BREP · manifold

canonical reference

REFERENCE

canonical · ground truth

1.000100✓

Zoo Text-to-CAD

Zoo (KittyCAD)

0.59411✗

Claude Opus 4.7 → CadQuery

Anthropic + CadQuery 2.4

0.5949✗

Human Baseline (Mech-E)

OpenAI + CadQuery 2.4

0.44911✗

Claude Opus 4.7 → OpenSCAD

Anthropic + OpenSCAD 2024.06

0.3830✗

DeepCAD

Wu et al. 2021 (research)

0.35616✗

Gemini 2.5 Pro → OpenSCAD

Google + OpenSCAD 2024.06

no manifold solid produced

Spline AI

Spline.design

—2✗

Each tile is rebuilt from the canonical parametric description and degraded to match the agent's scored profile (tessellation, non-manifold face removal, dimension scale jitter, missing features). Image-only diffusion models render visually plausible meshes but score in the single digits on BREP fidelity — the geometry is not a manifold solid even when the render reads clean.

§5Per-agent metrics

ranked by Vol IoU · same data as the leaderboard, restricted to this task

Agent	Watert.	Manif.	DFM	Min-Wall Compliance	CAM Reachability	p50	latency	cost
Zoo Text-to-CAD	✓	0.936	81.8	0.623	0.706	—	7.1s	$0.153
Claude Opus 4.7 → CadQuery	✓	0.936	82.4	0.622	0.683	—	46.2s	$0.330
Human Baseline (Mech-E)	✓	0.943	93.0	0.803	0.836	—	623.8s	$7.071
Adam (CADcrush)	✓	0.936	79.7	0.579	0.596	—	11.1s	$0.263
GPT-5 → CadQuery	✓	0.919	80.5	0.617	0.647	—	29.4s	$0.248
Claude Opus 4.7 → OpenSCAD	×	0.906	76.8	0.599	0.529	—	36.2s	$0.360
DeepCAD	×	0.905	64.6	0.338	0.343	—	4.7s	$0.022
Gemini 2.5 Pro → OpenSCAD	×	0.899	75.3	0.528	0.443	—	24.1s	$0.094
Trellis 3D	×	0.851	50.2	0.203	0.094	—	13.8s	$0.056
Spline AI kernel error: BRepCheck_NotClosed	×	0.000	—	—	—	—	9.4s	$0.035