STL Generator for Woodworking Jigs

Generate parametric 3D printable jigs and fixtures for woodworking projects using CadQuery.

Target Printer Specifications

• Printer: Elegoo Neptune 4 Pro
• Build volume: 225mm × 225mm × 265mm
• Layer height: 0.2mm standard
• Units: Metric (millimeters)

For complete specifications and design constraints, read references/printer_specs.md.

Available Pre-Built Scripts

1. Circle Cutting Jig (scripts/circle_cutting_jig.py)

Creates router jigs for cutting perfect circles - ideal for lampshade rings and circular frames.

Usage:

python scripts/circle_cutting_jig.py <outer_diameter> <inner_diameter> [output.stl]

Example:

python scripts/circle_cutting_jig.py 300 250 lampshade_jig.stl

Features:

• Adjustable inner/outer diameters
• Built-in guide ring for router stability
• Center pivot hole for compass-style cutting
• Radial slot for router bit clearance
• Alignment marks every 45°

2. Angle Wedge (scripts/angle_wedge.py)

Creates angle guide wedges for compound cuts and angled assembly work.

Usage:

python scripts/angle_wedge.py <angle_degrees> [output.stl]

Example:

python scripts/angle_wedge.py 15 wedge_15deg.stl

Features:

• Any angle from 1-60 degrees
• Raised reference edge on hypotenuse
• Embossed angle label
• Stable base for accurate positioning

3. Spacing Blocks (scripts/spacing_block.py)

Creates precision spacing blocks for consistent assembly gaps and setup.

Usage:

# Single block
python scripts/spacing_block.py <height_mm> [width_mm] [depth_mm] [output.stl]

# Set of multiple heights
python scripts/spacing_block.py set <h1>,<h2>,<h3> [output.stl]

Examples:

python scripts/spacing_block.py 10 50 30 spacer_10mm.stl
python scripts/spacing_block.py set 5,10,15,20 spacer_set.stl

Features:

• Embossed dimension labels
• Finger relief cutouts for easy pickup
• Orientation markers
• Can generate matched sets

Creating Custom Jigs

For custom jig designs not covered by pre-built scripts, write Python code using CadQuery. Read references/cadquery_patterns.md for common patterns and best practices.

Workflow for Custom Jigs

1. Understand requirements: Get dimensions, constraints, and functional needs
2. Check printer limits: Verify design fits within 225×225×265mm build volume
3. Apply design constraints: Use guidelines from references/printer_specs.md:
   • Minimum wall thickness: 2-3mm for structural parts
   • Hole clearances: +0.3-0.5mm for hardware
   • Minimum feature size: 1.0mm
   • Text depth: 0.4-0.6mm
4. Write CadQuery code: Use patterns from references/cadquery_patterns.md
5. Export to STL: Use cq.exporters.export(part, "filename.stl")
6. Save to outputs: Move STL file to /mnt/user-data/outputs/ for user access

Example: Custom Router Template

import cadquery as cq

def create_router_template(length, width, inset, guide_height):
    """Create router template with guide bushings."""
    
    # Base plate
    base = (
        cq.Workplane("XY")
        .rect(length, width)
        .extrude(6)
    )
    
    # Cut out center area
    base = (
        base.faces(">Z")
        .workplane()
        .rect(length - 2 * inset, width - 2 * inset)
        .cutThruAll()
    )
    
    # Add guide walls
    walls = (
        cq.Workplane("XY")
        .workplane(offset=6)
        .rect(length, width)
        .rect(length - 2 * inset, width - 2 * inset)
        .extrude(guide_height)
    )
    
    result = base.union(walls)
    
    # Add mounting holes (corners)
    for x in [-length/2 + 15, length/2 - 15]:
        for y in [-width/2 + 15, width/2 - 15]:
            result = (
                result.faces(">Z")
                .workplane()
                .center(x, y)
                .circle(2.5)  # M5 clearance
                .cutThruAll()
            )
    
    return result

# Generate and export
template = create_router_template(200, 150, 30, 8)
cq.exporters.export(template, "router_template.stl")

Common Jig Types and Approaches

Lampshade Jigs

• Circle cutting: Use circle_cutting_jig.py for ring frames
• Angle guides: Use angle_wedge.py for tapered shade angles
• Spacing: Use spacing_block.py for consistent rib spacing

Router Jigs

• Edge guides: Rectangular frame with adjustable fence
• Template guides: Match standard template bushing sizes (16mm OD common)
• Bit clearance: 7-8mm slots for 1/4" shanks, 13-14mm for 1/2"

Assembly Jigs

• Right angle corners: 90° blocks with reference edges
• Spacing sets: Multiple blocks for consistent gaps
• Alignment pins: 6mm diameter pins, 10mm height standard

Clamping Aids

• Cauls: Flat plates with finger reliefs
• Pressure distributors: Curved or stepped surfaces
• Clamp blocks: Sacrificial blocks with protective surfaces

Design Best Practices

Structural Integrity

• Use 3-4 perimeter walls for strength
• Add chamfers/fillets (1-2mm) to reduce stress concentrations
• Orient layer lines perpendicular to primary load direction
• Minimum 5mm base thickness for flatness

Printability

• Keep overhangs under 45° to avoid supports
• Add 0.2mm draft angle for parts that nest
• Avoid unsupported bridges over 30mm
• Orient largest flat surface on print bed

Woodworking Functionality

• Smooth reference surfaces (no text or features on work contact areas)
• Add visual alignment marks (notches, text, contrasting surfaces)
• Include finger reliefs on small parts for easy handling
• Consider clamping access (25mm+ clearance)

Hardware Integration

Common hole sizes (add 0.3-0.5mm clearance):

• M3: 3.3mm hole
• M4: 4.3mm hole
• M5: 5.3mm hole
• #8 wood screw: 4.5mm hole
• 1/4"-20 bolt: 6.6mm hole

File Organization

When generating STL files:

1. Work in /home/claude/ during development
2. Test scripts by running them to verify output
3. Copy final STLs to /mnt/user-data/outputs/ before presenting to user
4. Name files descriptively: Include key dimensions or purpose
   • Good: lampshade_jig_300mm_OD.stl
   • Good: wedge_22.5_degrees.stl
   • Poor: jig1.stl

CadQuery Quick Reference

For detailed patterns and examples, read references/cadquery_patterns.md.

Basic structure:

import cadquery as cq

# Create base
part = cq.Workplane("XY").box(50, 30, 10)

# Add features on top
part = (
    part.faces(">Z")
    .workplane()
    .circle(5)
    .cutThruAll()
)

# Export
cq.exporters.export(part, "output.stl")

Essential methods:

• .box(w, d, h) - rectangular solid
• .circle(r) - circle sketch
• .rect(w, h) - rectangle sketch
• .extrude(height) - extrude 2D to 3D
• .cutThruAll() - cut through entire part
• .fillet(radius) - round edges
• .chamfer(distance) - bevel edges
• .translate((x, y, z)) - move part
• .rotate((cx,cy,cz), (ax,ay,az), angle) - rotate around axis

Troubleshooting

"Module 'cadquery' not found"

pip install --break-system-packages cadquery

STL appears hollow in slicer

• This is normal - slicers add infill during slicing
• The generated STL is a shell (surface model)

Features too small to print

• Check minimum feature size: 1.0mm
• Increase wall thickness to at least 2-3mm
• Verify hole diameters are >= 2mm

Part doesn't fit on print bed

• Check dimensions against 220×220mm effective area
• Consider splitting large jigs into sections
• Rotate part to minimize footprint

When to Read Reference Files

• Always read references/printer_specs.md when starting a new jig design
• Read references/cadquery_patterns.md when writing custom CadQuery code
• Refer to examples in pattern files for complex geometries

Output Format

After generating STL file(s), always:

1. Move final STLs to /mnt/user-data/outputs/
2. Provide download link: [View your file](computer:///mnt/user-data/outputs/filename.stl)
3. Include brief summary: dimensions, purpose, estimated print time
4. Suggest print settings if relevant (infill %, supports, orientation)