# Cadquery Manufacturability

> Apply a Design-for-Manufacture (DFM) pass to a CadQuery part by inspecting it against its presumed manufacturing process (machining, sheet-metal, 3D print, casting/molding) and adding the missing manufacturability features — minimum wall thickness, draft, tap-drill holes, counterbore depths, mounting-hole patterns, vendor-part procurement-grade comments, engraved part numbers, weld-bead notes, snap-fit undercuts. Use after `cadquery-part-detailing` finishes the geometric finish, when the user says "make this manufacturable", "add DFM features", "this should be machinable", or before final STEP export.

- Skill: `leoai-org/cadquery-manufacturability` (Agent Skill)
- Install (CLI): `npx skillmds@latest add leoai-org/cadquery-manufacturability`
- Raw SKILL.md: https://api.skillmd.com/api/skills/leoai-org/cadquery-manufacturability/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: leoai-org (https://skillmd.com/u/leoai-org)
- Updated: 2026-09-22
- Page: https://skillmd.com/skills/leoai-org/cadquery-manufacturability

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# CadQuery manufacturability — DFM pass

## Purpose

Make the part **manufacturable and sourceable**: correct fastener diameters, counterbores, process constraints, vendor BOM text, identification engraving. Run **after** detailing so counterbores are not destroyed by later fillets.

## What this pass is NOT

- No structural ribs/gussets (detailing)
- No cosmetic fillets unless **process-required** (e.g. cast fillet note in comment when radius already exists in detailing)
- No changing functional mate diameters without updating `common.py` and the partner part

## Authoritative rules

`cad-generation.txt` — Mechanical Interfaces, Standard Vendor Parts.

## Inputs

- Detailed part file from `cadquery-part-detailing`
- Mating list: joint kind per partner
- Process: machined | sheet_metal | print | cast
- Which side of each bolted joint this part is (**clamped** → clearance; **receiver** → tap pilot)

## Fastener responsibility split (critical)

For each bolted mate, **exactly one part** gets clearance + counterbore; the **partner** gets tap pilot — positions from `common.py`:

```python
# common.py
M3_MOUNT_PTS = [(30, 15), (-30, 15), (30, -15), (-30, -15)]

# parts/bracket.py (clamped) — DFM pass
from common import M3_MOUNT_PTS, M3_CLEAR_DIA, M3_CBORE_DIA, M3_CBORE_DEPTH, PLATE_T
clear = cq.Workplane("XY").pushPoints(M3_MOUNT_PTS).circle(M3_CLEAR_DIA / 2).extrude(PLATE_T + 1)
cbore = cq.Workplane("XY").pushPoints(M3_MOUNT_PTS).circle(M3_CBORE_DIA / 2).extrude(-M3_CBORE_DEPTH)
bracket = bracket.cut(clear).cut(cbore)

# parts/base.py (receiver) — DFM pass
from common import M3_MOUNT_PTS, M3_TAP_DIA, TAP_DEPTH
pilot = cq.Workplane("XY").pushPoints(M3_MOUNT_PTS).circle(M3_TAP_DIA / 2).extrude(-TAP_DEPTH)
base = base.cut(pilot)
```

Never put both clearance and tap on the same part unless it is a standalone test piece.

### Fastener table (mm)

| Thread | Clearance Ø | Tap-drill Ø | Counterbore Ø × depth |
|--------|-------------|-------------|------------------------|
| M3 | 3.4 | 2.5 | 6.0 × 3.0 |
| M4 | 4.5 | 3.3 | 8.0 × 4.0 |
| M5 | 5.5 | 4.2 | 10.0 × 5.0 |
| M6 | 6.4 | 5.0 | 11.0 × 6.0 |
| M8 | 8.4 | 6.8 | 14.0 × 8.0 |
| M10 | 10.5 | 8.5 | 17.5 × 10.0 |

Define `M3_CLEAR_DIA`, `M3_TAP_DIA`, etc. in `common.py` when first used.

## DFM checklist

Apply every item that fits:

### All processes

- **Mounting holes** on anything that bolts to another surface — even if mate part is out of scope
- **Vendor procurement comment** (4 lines: category, key dims, standard, sample SKU) above interface geometry
- **Part identification** on a non-cosmetic face: `.faces("<Z").workplane().text("P/N …", 4, -0.3, combine="cut")`

### Press-fit / welded / snap

- Press-fit: document interference in comment; model zero gap
- Welded: flush faces + `# WELD — fillet weld along ...` comment
- Snap-fit: explicit undercut dimension in comment + modeled beam/ledge

### Machined

- Min wall 1.5 mm (Al), 1.0 mm (steel)
- No sharp internal pocket corners without noting min cutter radius (detailing should have fillet)

### Sheet metal

- Uniform thickness; bend radius ≥ t; hole-to-edge ≥ 2t

### 3D print

- Min wall ≥ 1.2 mm; no modeled threads — clearance + comment for insert

### Cast / molded

- 1–3° draft on vertical walls (model or comment)
- Uniform wall ±25%

## Build order

1. Re-open `parts/<name>.py` inside `build_*()` after detailing block.
2. Add `# ---- DFM ----` section.
3. Each cut/union: **single-extrusion tool**, one at a time.
4. Vendor comments immediately above related geometry.
5. Return part; keep `result = build_<name>()`.

## Workflow

1. Edit part file.
2. Smoke exec + orchestrator **`cadquery-render`**.
3. Orchestrator **`cadquery-interference-check`** — counterbores often clash with neighbors.

## Output

Updated `parts/<function_name>.py`. Do not modify `assembly.py` — orchestrator swaps the built part.