Overview

This guide explains the different toolpath clearance strategies available in Carveco and helps you choose the most suitable one for your machining projects. These strategies determine how the tool moves across the surface of your relief during finishing, impacting quality, tool life, and machining time.

1. 3D Offset (Spiral)

• Description: Tool moves in a continuous spiral, typically starting from the outside and working inward (or vice versa).
• Best For: Sculpted reliefs requiring smooth contour-following motion.
• Advantages: Fewer directional changes = smoother finish. Ideal for full relief surface coverage.
• Disadvantages: Slow to process and machine. High tool wear, especially on outer loops.
• Usage Tips: Use a sharp tool with good chip clearance. Increase feed-rate slightly to reduce air cutting time.

2. Raster (X or Y)

• Description: Tool moves in straight lines along either the X or Y axis, stepping over incrementally.
• Best For: Rectangular or geometric designs.
• Advantages: Fast processing. Simple and predictable.
• Disadvantages: Can leave visible lines or cusps. May produce uneven surface quality on curved areas.
• Usage Tips: Try alternating the axis (X or Y) to suit the shape of your model. Use a stepover of 10% or less for cleaner results.

3. Raster X & Y (Cross-Hatch)

• Description: Tool first rasters along X, then again along Y, providing coverage from two directions.
• Best For: High-detail precision work.
• Advantages: Excellent surface finish. Minimal cusp marks.
• Disadvantages: Doubles machining time compared to single raster.
• Usage Tips: Ideal when fine surface texture is required. Combine with a small tool and tight stepover for best results.

4. Spiral Within a Box

• Description: Similar to 3D offset but covers the entire bounding box of the relief, regardless of relief shape.
• Best For: Square or rectangular reliefs where complete coverage is required.
• Advantages: Uniform surface engagement. Smooth tool motion.
• Disadvantages: Inefficient air cutting in unused corners. Slightly longer toolpath calculations.
• Usage Tips: Use on large models to avoid missing edge material. Combine with vector boundaries if partial coverage is acceptable.

5. Centerline Strategy (special case)

• Description: Used in 2D or 2.5D centerline-based designs, tool follows vector lines.
• Best For: Geometric engraving, line art.
• Advantages: Minimal tool travel. Highly precise for narrow features.
• Disadvantages: Not applicable for full reliefs.
• Usage Tips: Ensure vector start/end points are optimized to reduce rapid movements. Works best with V-bits or small conical tools.

Choosing the Right Strategy

• For full detailed reliefs, start with Spiral or Spiral-in-a-Box for consistent coverage.
• For faster generation, Raster X & Y can provide excellent results with shorter toolpath processing.
• For minimal surface variation, use Raster X & Y with fine stepover.
• For less critical areas, Raster (X or Y) is suitable and efficient.
• Tip: Preview simulations to evaluate surface quality before sending to machine.