Operations Guide

Detailed guide for all CNC operations in GScript.

Overview

GScript provides four core operation types for common CNC machining tasks:

• Face - Surface milling
• Drill - Point drilling
• Pocket - Rectangular pocket clearing
• Contour - Profile cutting

Each operation is optimized for its specific machining task and generates efficient toolpaths automatically.

##Face Operations

Surface milling to create flat reference surfaces or remove material evenly.

When to Use

• Facing stock to create a flat reference surface
• Removing material from large areas
• Achieving specific thickness
• Creating flat bottoms for pockets

Parameters

See the Language Reference - Face Operation for complete syntax.

Example

- op: face
  tool: endmill-12mm
  depth: 2.0
  pass_depth: 0.5
  feed: 1200
  bounds: rect(0, 0, 100, 80)

Tips

• Use larger diameter tools (10-20mm) for efficiency
• Lower stepover (60-75%) for better surface finish
• Multiple shallow passes better than single deep pass
• Consider climb milling for better finish

---

Drill Operations

Drilling holes at specific locations.

When to Use

• Creating mounting holes
• Pilot holes for tapping
• Clearance holes
• Alignment pins

Parameters

See the Language Reference - Drill Operation for complete syntax.

Example

- op: drill
  tool: drill-5mm
  depth: 8.0
  feed: 300
  locations:
    - {x:10, y:10, z:0}
    - {x:90, y:10, z:0}
    - {x:10, y:70, z:0}
    - {x:90, y:70, z:0}

Tips

• Use peck drilling for deep holes (depth > 3x diameter)
• Lower feed rates for harder materials
• Center drill first for accurate positioning
• Use proper drill speeds (higher RPM = cleaner holes)

---

Pocket Operations

Clearing rectangular pockets or recesses.

When to Use

• Creating recesses for components
• Clearance pockets
• Weight reduction pockets
• Inset features

Parameters

See the Language Reference - Pocket Operation for complete syntax.

Example

- op: pocket
  tool: endmill-6mm
  depth: 5.0
  pass_depth: 1.5
  feed: 800
  bounds: rect(20, 20, 60, 40)
  strategy: spiral

Strategies

• Climb: Best for most materials, better surface finish
• Conventional: Better for soft/sticky materials
• Spiral: Efficient for square pockets

Tips

• Use 50% stepover for roughing, 25% for finishing
• Smaller tools for tighter corners
• Multiple passes at increasing depth
• Consider roughing pass then finishing pass

---

Contour Operations

Following a path for profile cutting, including smooth curves with arcs and splines.

When to Use

• Cutting part outlines
• Profile milling
• Creating complex shapes with curves
• Rounded corners and fillets
• Edge finishing

Parameters

See the Language Reference - Contour Operation for complete syntax.

Example: Linear Path

- op: contour
  tool: endmill-4mm
  depth: 10.0
  pass_depth: 2.0
  feed: 600
  closed: true
  path:
    - {x:0, y:0, z:0}
    - {x:100, y:0, z:0}
    - {x:100, y:80, z:0}
    - {x:0, y:80, z:0}

Example: With Rounded Corners (Arcs)

- op: contour
  tool: endmill-6mm
  depth: 3.0
  feed: 800
  closed: true
  path:
    - {x:10, y:0}
    - {x:90, y:0}
    - arc:{radius:10, end:{x:100, y:10}}
    - {x:100, y:70}
    - arc:{radius:10, end:{x:90, y:80}}
    - {x:10, y:80}
    - arc:{radius:10, end:{x:0, y:70}}
    - {x:0, y:10}
    - arc:{radius:10, end:{x:10, y:0}}

Example: Smooth Curves (Splines)

- op: contour
  tool: endmill-4mm
  depth: 5.0
  feed: 600
  path:
    - {x:0, y:0}
    - spline:{points:[{x:25, y:15}, {x:50, y:20}, {x:75, y:15}], tension:0.5}
    - {x:100, y:0}

Arc Notation

Arcs are defined with:

• radius: Arc radius in current units
• end: Arc endpoint coordinates (2D: x,y)
• clockwise: Optional, direction of arc (default: false/counter-clockwise)

Important: No spaces after colons in coordinates for YAML compatibility.

Spline Notation

Splines create smooth curves through control points:

• points: Array of 2D points the curve passes through
• tension: Optional, curve tightness (default: 0.5, range: 0.0-1.0)

Tips

• Use smaller tools for tighter radii
• Arcs are automatically linearized based on tolerance
• Lead-in/lead-out for cleaner starts
• Multiple passes for better finish
• Consider tool deflection on deep cuts
• Splines are ideal for organic shapes

---

Choosing the Right Operation

Task	Operation	Tool Type
Flat surface	Face	Large endmill
Holes	Drill	Drill bit
Rectangular recess	Pocket	Endmill
Part outline	Contour	Small endmill

---

Next Steps

• Language Reference - Complete syntax guide
• Tools Guide - Tool selection
• Examples - Working examples
• CLI Commands - Compiling programs